[{"id":"albatross-dynamic-soar","t":"nature","q":"Why can an albatross glide for thousands of kilometres over the ocean without flapping?"},{"id":"alligator-mouth-carry","t":"nature","q":"Why does a mother alligator gently carry her babies inside her own jaws?"},{"id":"alligator-nose-through-ice","t":"nature","q":"Why does an alligator poke just its nose through ice instead of finding warmer water?"},{"id":"amphibian-breed-in-water-mostly","t":"nature","q":"Why do most amphibians still need to return to water to lay their eggs?"},{"id":"amphibian-cant-live-in-saltwater","t":"nature","q":"Why do almost no frogs or salamanders live in the sea?"},{"id":"amphibian-decline-pollution","t":"nature","q":"Why do scientists check amphibians first to tell if a wetland is polluted?"},{"id":"amphibian-name-meaning","t":"nature","q":"Why are frogs, toads and salamanders all grouped together as \"amphibians\"?"},{"id":"amphisbaenian-worm-lizard","t":"nature","q":"Why can some legless reptiles move backwards just as easily as forwards?"},{"id":"amurfalcon-indianocean-nonstop","t":"nature","q":"Why does a small falcon fly nonstop across an entire ocean on its way to Africa?"},{"id":"anaconda-size-water","t":"nature","q":"Why do the biggest, heaviest snakes live mostly in water?"},{"id":"anole-dewlap-display","t":"nature","q":"Why do some lizards flash a bright flap of skin under their chin?"},{"id":"ant-colony-jobs","t":"nature","q":"Why do ants have queens, soldiers and workers instead of every ant being the same?"},{"id":"ant-pheromone-trails","t":"nature","q":"Why do ants walk in such tidy, unbroken lines?"},{"id":"ant-raft-bridges","t":"nature","q":"Why can ants link their own bodies into a raft, a bridge, or even a tower?"},{"id":"ant-stridulate-rescue-call","t":"nature","q":"Why do some trapped ants make a sound too high for us to hear?"},{"id":"ant-super-strength","t":"nature","q":"Why can an ant carry something fifty times its own weight?"},{"id":"apical-dominance-pruning","t":"nature","q":"Why does cutting off the top of a young tree make it grow bushier instead of taller?"},{"id":"arctic-fox-seasonal-camouflage","t":"nature","q":"Why does an Arctic fox wear two completely different coats across one year?"},{"id":"arctic-groundsquirrel-supercool","t":"nature","q":"Why can an Arctic ground squirrel's blood get colder than freezing without freezing solid?"},{"id":"arum-lily-trap-flower","t":"nature","q":"Why does the cuckoo pint flower trap flies overnight before letting them go?"},{"id":"assassin-bug-ant-disguise","t":"nature","q":"Why do some assassin bugs pile dead ants on their own backs?"},{"id":"australian-burrowing-frog-cocoon","t":"nature","q":"Why does an Australian desert frog wrap itself in its own shed skin before a drought?"},{"id":"avocado-lost-partner","t":"nature","q":"Why does an avocado seed seem too big for any animal alive today to swallow whole?"},{"id":"axolotl-never-grows-up","t":"nature","q":"Why does an axolotl keep its feathery gills forever instead of growing up like other salamanders?"},{"id":"axolotl-regrow-legs","t":"nature","q":"Why can an axolotl regrow a whole leg if it loses one?"},{"id":"baby-bird-touch-myth","t":"nature","q":"Why won't touching a baby bird make its parents abandon it?"},{"id":"baby-turtle-find-sea","t":"nature","q":"Why do baby turtles all scramble straight for the sea the moment they hatch?"},{"id":"bamboo-not-a-tree","t":"nature","q":"Why isn't bamboo actually classified as a tree, even though it can look like one?"},{"id":"banksia-fire-release","t":"nature","q":"Why do some Australian seed pods only open after a bushfire?"},{"id":"banyan-many-trunks","t":"nature","q":"Why do banyan trees grow trunks that look like a whole forest all by themselves?"},{"id":"barheaded-goose-everest-altitude","t":"nature","q":"Why can a bar-headed goose fly over the top of Mount Everest?"},{"id":"bark-function","t":"nature","q":"Why do trees have bark?"},{"id":"bark-peeling-strips","t":"nature","q":"Why do some trees peel their bark off in long strips?"},{"id":"basilisk-run-on-water","t":"nature","q":"Why can some lizards run across the surface of water?"},{"id":"bat-cant-walk-vampire-exception","t":"nature","q":"Why are most bats so clumsy and slow moving around on the ground?"},{"id":"bat-hibernation-hanging","t":"nature","q":"Why do hibernating bats hang upside down instead of curling up on a cave floor?"},{"id":"bat-migration-instead-hibernate","t":"nature","q":"Why do some bats fly thousands of kilometres south instead of hibernating for winter?"},{"id":"bat-pollinated-flowers","t":"nature","q":"Why do some flowers open only at night and smell like sour fruit?"},{"id":"bat-social-calls-not-echolocation","t":"nature","q":"Why do bats have a separate set of calls just for talking to each other, apart from echolocation?"},{"id":"bats-dark","t":"nature","q":"Why can bats fly in the dark?"},{"id":"beak-material","t":"nature","q":"Why doesn't a bird's beak wear away to nothing after years of pecking?"},{"id":"beak-no-teeth","t":"nature","q":"Why don't birds have teeth?"},{"id":"beak-shapes-diet","t":"nature","q":"Why do different birds have such completely different shaped beaks?"},{"id":"bear-cub-tiny-den","t":"nature","q":"Why are bear cubs born so tiny while their mother hibernates?"},{"id":"bear-hibernation-myth","t":"nature","q":"Why don't bears really \"hibernate\" the way scientists usually define it?"},{"id":"beaver-tail-slap-alarm","t":"nature","q":"Why does a beaver slap its tail on the water so loudly?"},{"id":"bee-color-blue-purple","t":"nature","q":"Why do bees seem to visit blue and purple flowers so often?"},{"id":"bee-electric-field-flowers","t":"nature","q":"Why can a bumblebee tell a flower has already been visited before it even lands?"},{"id":"bee-pollen-basket","t":"nature","q":"Why do bees carry two yellow lumps on their back legs?"},{"id":"bee-pollen-vs-nectar-purpose","t":"nature","q":"Why do bees collect pollen and nectar separately instead of just one or the other?"},{"id":"bee-tongue-proboscis","t":"nature","q":"Why does a bee's tongue look furry instead of smooth like a straw?"},{"id":"bee-uv-flowers","t":"nature","q":"Why does a plain yellow flower look completely different to a bee?"},{"id":"bees-dance","t":"nature","q":"Why do bees dance?"},{"id":"beetle-wing-covers","t":"nature","q":"Why do beetles have a hard shell covering their wings?"},{"id":"beetles-most-numerous","t":"nature","q":"Why are beetles the most common kind of animal alive?"},{"id":"berry-ripen-color-signal","t":"nature","q":"Why do berries turn bright red or purple exactly when their seeds are finally ready?"},{"id":"big-seed-small-seed-tradeoff","t":"nature","q":"Why do some plants make thousands of tiny seeds while others make just a few huge ones?"},{"id":"bigcat-pupil-shape","t":"nature","q":"Why do lions have round pupils but small cats have narrow, slit-shaped ones?"},{"id":"bigcat-roar-hyoid","t":"nature","q":"Why can lions, tigers, leopards and jaguars roar but most cats can't?"},{"id":"biggest-tree-not-tallest","t":"nature","q":"Why is the world's most massive tree not also the tallest?"},{"id":"bilby-big-ears","t":"nature","q":"Why do bilbies have such huge ears for their body size?"},{"id":"bilby-easter-swap","t":"nature","q":"Why is the bilby becoming Australia's alternative Easter symbol instead of the rabbit?"},{"id":"bird-air-sacs","t":"nature","q":"Why do birds need air sacs as well as lungs to breathe?"},{"id":"bird-building-collision-migration","t":"nature","q":"Why do bright city lights confuse migrating birds so badly at night?"},{"id":"bird-chick-gape-colour","t":"nature","q":"Why does a baby bird's open mouth flash such a bright colour inside?"},{"id":"bird-feet-cold","t":"nature","q":"Why don't a bird's feet freeze when it stands on an icy branch all night?"},{"id":"bird-few-tastebuds","t":"nature","q":"Why do birds seem to swallow food fast without really tasting it much?"},{"id":"bird-fuel-fat-before-migration","t":"nature","q":"Why do migrating birds sometimes double their body weight before they leave?"},{"id":"bird-hidden-ears","t":"nature","q":"Why can't you see a songbird's ears, even though its hearing is excellent?"},{"id":"bird-hollow-bones","t":"nature","q":"Why do birds have hollow bones instead of solid ones like ours?"},{"id":"bird-keel","t":"nature","q":"Why do flying birds have a huge blade of bone running down the middle of their chest?"},{"id":"bird-magnetic-compass-one-eye","t":"nature","q":"Why can a robin's magnetic compass sense work best through just one eye?"},{"id":"bird-migratory-restlessness-zugunruhe","t":"nature","q":"Why does a caged bird flutter toward one direction every night in migration season?"},{"id":"bird-moult","t":"nature","q":"Why do birds lose their feathers and grow new ones every year?"},{"id":"bird-night-migration-reasons","t":"nature","q":"Why do most small birds migrate at night instead of during the day?"},{"id":"bird-perch-lock","t":"nature","q":"Why doesn't a sleeping bird fall off its branch?"},{"id":"bird-syrinx","t":"nature","q":"Why can some birds sing two different notes at exactly the same time?"},{"id":"bird-uv-vision","t":"nature","q":"Why can birds see colours that are completely invisible to us?"},{"id":"birds-migrate","t":"nature","q":"Why do birds fly south for winter?"},{"id":"birds-on-wires","t":"nature","q":"Why don't birds get a shock sitting on a power line?"},{"id":"birds-sing","t":"nature","q":"Why do birds sing in the morning?"},{"id":"black-cockatoo-rain","t":"nature","q":"Why do people say seeing black cockatoos flying over means rain is coming?"},{"id":"blackpanther-not-species","t":"nature","q":"Why is there no such animal as a \"black panther\"?"},{"id":"bluetongue-flash-tongue","t":"nature","q":"Why does a blue-tongued lizard flash its blue tongue at predators?"},{"id":"bogong-moth-migration","t":"nature","q":"Why do millions of Australian moths fly hundreds of kilometres to sleep in mountain caves?"},{"id":"bombardier-beetle-spray","t":"nature","q":"Why can a bombardier beetle blast a predator with boiling-hot spray?"},{"id":"bowerbird-display-not-song","t":"nature","q":"Why does a male bowerbird build and decorate a structure instead of just singing for a mate?"},{"id":"boxer-crab-anemone-gloves-2","t":"nature","q":"Why does a boxer crab carry a stinging sea anemone in each claw?"},{"id":"boxturtle-land-winter-dormancy","t":"nature","q":"Why does a box turtle dig itself into soil instead of finding water for winter?"},{"id":"branch-height-fixed","t":"nature","q":"Why does a branch low on a tree trunk stay at the same height as the tree grows taller?"},{"id":"bread-mould","t":"nature","q":"Why does mould grow on bread?"},{"id":"brood-patch","t":"nature","q":"Why do parent birds pluck the feathers from their own belly before sitting on eggs?"},{"id":"brushtail-possum-noise","t":"nature","q":"Why do brushtail possums make such loud, scary noises at night?"},{"id":"bud-dormancy-spring-signal","t":"nature","q":"Why do tree buds wait for a certain signal before bursting open in spring?"},{"id":"budgie-beakgrind","t":"nature","q":"Why do budgies grind their beaks before falling asleep?"},{"id":"budgie-cere","t":"nature","q":"Why does a budgie's nose patch change colour?"},{"id":"budgie-flight","t":"nature","q":"Why do budgies need to fly, not just walk around?"},{"id":"budgie-oneeye","t":"nature","q":"Why does a budgie look at you side-on with one eye?"},{"id":"budgie-regurgitate","t":"nature","q":"Why do budgies sometimes bring up food for their favourite toy?"},{"id":"budgie-talk","t":"nature","q":"Why can budgies learn to copy human words?"},{"id":"bull-ant-sting-australia","t":"nature","q":"Why do Australian bull ants have such a painful sting?"},{"id":"bull-red-cape","t":"nature","q":"Why do bulls charge at a red cape?"},{"id":"bumblebee-cold-flight","t":"nature","q":"Why can bumblebees fly on cold mornings when honeybees stay home?"},{"id":"burdock-velcro-hook","t":"nature","q":"Why do burdock burrs cling so stubbornly to a dog's fur?"},{"id":"butterfly","t":"nature","q":"Why do caterpillars turn into butterflies?"},{"id":"butterfly-pollinated-flower-shape","t":"nature","q":"Why do butterflies visit flat, wide flowers more than deep, tube-shaped ones?"},{"id":"butterfly-taste-feet","t":"nature","q":"Why do butterflies taste a leaf with their feet before laying eggs on it?"},{"id":"buttress-roots","t":"nature","q":"Why do some rainforest trees grow giant wall-like roots above the ground?"},{"id":"buzz-pollination-tomato","t":"nature","q":"Why do bumblebees shake tomato flowers so hard without touching them?"},{"id":"cacao-flower-midge-2","t":"nature","q":"Why is chocolate so hard for farmers to grow enough of?"},{"id":"cactus-spikes","t":"nature","q":"Why do cacti have spikes?"},{"id":"caecilian-legless","t":"nature","q":"Why do caecilians look like giant earthworms even though they're amphibians?"},{"id":"caecilian-tentacle-smell","t":"nature","q":"Why does a caecilian have a small tentacle poking out near its mouth?"},{"id":"camel-spider-not-spider","t":"nature","q":"Why do \"camel spiders\" look terrifying even though they aren't dangerous at all?"},{"id":"cane-toad-invasive-australia","t":"nature","q":"Why are cane toads such a serious problem for native Australian animals?"},{"id":"caribou-migration-greenup-timing","t":"nature","q":"Why do caribou herds time their migration to arrive exactly when new grass appears?"},{"id":"caribou-river-crossing-drowning","t":"nature","q":"Why is crossing a swollen river one of the most dangerous parts of a caribou's migration?"},{"id":"carrion-fly-egg-trick","t":"nature","q":"Why do some flowers smell like dung or dead meat instead of perfume?"},{"id":"cassowary-claw-weapon","t":"nature","q":"Why is a cassowary's inner claw considered a dangerous weapon?"},{"id":"cassowary-helmet","t":"nature","q":"Why does a cassowary carry a tall, bony helmet on top of its head?"},{"id":"cat-scruff-carry","t":"nature","q":"Why does a mother cat carry her kittens by the scruff of the neck without hurting them?"},{"id":"cat-whisker-gap-judge","t":"nature","q":"Why does a cat pause to measure a narrow gap with its whiskers before squeezing through?"},{"id":"catfish-taste-skin","t":"nature","q":"Why can a catfish taste something before it even reaches its mouth?"},{"id":"cats-eyeshine","t":"nature","q":"Why do cats' eyes glow in the dark?"},{"id":"cats-gifts","t":"nature","q":"Why do cats bring home dead animals?"},{"id":"cats-headbutt","t":"nature","q":"Why do cats headbutt you?"},{"id":"cats-knead","t":"nature","q":"Why do cats knead with their paws?"},{"id":"cats-land","t":"nature","q":"Why do cats land on their feet?"},{"id":"cats-meow-humans","t":"nature","q":"Why do adult cats mostly meow at people and not at each other?"},{"id":"cats-pupils","t":"nature","q":"Why do cats have slit-shaped pupils instead of round ones?"},{"id":"cats-purr","t":"nature","q":"Why do cats purr?"},{"id":"cats-scratch","t":"nature","q":"Why do cats scratch furniture?"},{"id":"cats-sweet","t":"nature","q":"Why can't cats taste anything sweet?"},{"id":"cats-tongue","t":"nature","q":"Why is a cat's tongue so rough?"},{"id":"centipede-forcipules","t":"nature","q":"Why do centipedes bite with modified legs instead of teeth?"},{"id":"centipede-odd-leg-pairs","t":"nature","q":"Why do centipedes always have an odd number of pairs of legs?"},{"id":"centipede-venom-danger","t":"nature","q":"Why can a centipede bite hurt but almost never kill a person?"},{"id":"chameleon","t":"nature","q":"Why do chameleons change colour?"},{"id":"chameleon-independent-eyes","t":"nature","q":"Why can a chameleon's eyes look in two different directions at once?"},{"id":"cheetah-claws","t":"nature","q":"Why doesn't a cheetah's claws retract like other cats' do?"},{"id":"cheetah-cub-mane","t":"nature","q":"Why do cheetah cubs have a fluffy silver mane running down their backs?"},{"id":"cheetah-no-roar","t":"nature","q":"Why can't a cheetah roar like a lion?"},{"id":"cheetah-speed-endurance","t":"nature","q":"Why can't a cheetah keep sprinting for very long?"},{"id":"cheetah-tail-rudder","t":"nature","q":"Why does a cheetah have such a long, flat tail?"},{"id":"cheetah-tearlines","t":"nature","q":"Why do cheetahs have black lines running from their eyes down to their mouth?"},{"id":"chickadee-torpor-cold-nights","t":"nature","q":"Why can a tiny chickadee survive a freezing night when a similarly sized bird might not?"},{"id":"chicken-broody","t":"nature","q":"Why do hens sit on eggs that will never hatch?"},{"id":"chicken-cant-fly-far","t":"nature","q":"Why can't chickens fly very far?"},{"id":"chicken-comb","t":"nature","q":"Why do chickens have a floppy red comb on their head?"},{"id":"chicken-dust-bath","t":"nature","q":"Why do chickens take dust baths?"},{"id":"chicken-egg-colour","t":"nature","q":"Why do some hens lay brown eggs and others white?"},{"id":"chicken-no-rooster-needed","t":"nature","q":"Why do hens lay eggs even without a rooster?"},{"id":"chicken-pecking-order","t":"nature","q":"Why do chickens have a \"pecking order\"?"},{"id":"chicken-see-uv","t":"nature","q":"Why do chickens see colours we can't?"},{"id":"chilli-pepper-bird-seed","t":"nature","q":"Why are chillies fiery hot to us but not to the birds that eat them?"},{"id":"chimpanzee-panting-laugh","t":"nature","q":"Why does a chimpanzee's laugh sound like panting instead of 'ha ha ha'?"},{"id":"chinchilla-fur-slip","t":"nature","q":"Why does a grabbed chinchilla leave a bald patch of fur behind in a predator's grip?"},{"id":"chinese-giant-salamander-name","t":"nature","q":"Why is the Chinese giant salamander nicknamed the \"infant fish\"?"},{"id":"chipmunk-not-true-hibernator","t":"nature","q":"Why does a chipmunk wake itself up every few days all winter, unlike a true hibernator?"},{"id":"cicada-loud-song","t":"nature","q":"Why are cicadas so loud?"},{"id":"cicada-males-only-sing","t":"nature","q":"Why can male cicadas sing but female cicadas stay silent?"},{"id":"cicada-prime-years","t":"nature","q":"Why do some cicadas hide underground for exactly 13 or 17 years?"},{"id":"cicada-shell-shed","t":"nature","q":"Why do papery insect shells cling to tree trunks in summer?"},{"id":"cleavers-hook-hitch","t":"nature","q":"Why does goosegrass stick to your jumper the moment you brush past it?"},{"id":"clickbeetle-jump-spring","t":"nature","q":"Why can a click beetle flip itself into the air without using its legs at all?"},{"id":"cloudedleopard-canines","t":"nature","q":"Why does a clouded leopard have such enormous fangs for its size?"},{"id":"coastal-wind-pruned-trees","t":"nature","q":"Why do trees on a windy coastline sometimes grow permanently leaning away from the sea?"},{"id":"cocklebur-double-hook","t":"nature","q":"Why does a cocklebur seed case have two different kinds of spikes?"},{"id":"cockroach-cerci-airsense","t":"nature","q":"Why can a cockroach dodge a hand before it has even finished swinging?"},{"id":"coco-de-mer-giant-seed","t":"nature","q":"Why does the world's biggest seed barely travel anywhere at all?"},{"id":"coconut-ocean-drift","t":"nature","q":"Why can a coconut float across an ocean and still grow into a tree?"},{"id":"cone-snail-harpoon-venom","t":"nature","q":"Why does a slow-moving cone snail have one of the fastest weapons in the ocean?"},{"id":"coppicing-stump-regrowth","t":"nature","q":"Why can some trees grow back into a full tree after being cut right down to a stump?"},{"id":"coqui-frog-direct-development","t":"nature","q":"Why does a coqui frog hatch straight into a tiny frog instead of a tadpole?"},{"id":"coral-snake-rhyme-limits","t":"nature","q":"Why doesn't the 'red touch yellow, kill a fellow' snake rhyme work everywhere?"},{"id":"cork-oak-repeated-harvest","t":"nature","q":"Why can bark be stripped from a cork oak again and again without killing the tree?"},{"id":"corpse-flower-heat","t":"nature","q":"Why does the giant corpse flower warm itself up like a living body?"},{"id":"cougar-no-roar","t":"nature","q":"Why can't a cougar roar even though people sometimes call it a \"mountain lion\"?"},{"id":"countershading-fish-belly","t":"nature","q":"Why are so many fish, birds and sharks dark on top and pale underneath?"},{"id":"cow-four-teats","t":"nature","q":"Why do cows have four teats?"},{"id":"cow-milk-surplus","t":"nature","q":"Why do dairy cows make so much more milk than a calf needs?"},{"id":"cow-no-horns","t":"nature","q":"Why do some cows never grow horns?"},{"id":"cow-patchy-coat","t":"nature","q":"Why do cows have blotchy black-and-white patches instead of one plain colour?"},{"id":"cows-chew","t":"nature","q":"Why are cows always chewing?"},{"id":"crab-sideways-walk","t":"nature","q":"Why do most crabs walk sideways instead of forward?"},{"id":"cricket-chirp-temperature","t":"nature","q":"Why do crickets chirp faster on a warm night than a cold one?"},{"id":"cricket-leg-ears","t":"nature","q":"Why do crickets have ears on their front legs instead of their heads?"},{"id":"crocodile-bite-force-weak-open","t":"nature","q":"Why can a person sometimes hold a crocodile's jaws shut with just their hands?"},{"id":"crocodile-dome-pressure","t":"nature","q":"Why can a crocodile feel a raindrop land on a still pond from metres away?"},{"id":"crocodile-egg-chirp","t":"nature","q":"Why do baby crocodiles call out to each other before they've even hatched?"},{"id":"crocodile-float-like-log","t":"nature","q":"Why do crocodiles float so still, looking just like a log?"},{"id":"crocodile-tears-real","t":"nature","q":"Why do crocodiles really cry while eating?"},{"id":"crocodile-vs-alligator-snout","t":"nature","q":"Why do crocodiles and alligators have such different-shaped snouts?"},{"id":"crow-face-memory","t":"nature","q":"Why do crows remember a particular human face for years?"},{"id":"crow-gesture-pointing","t":"nature","q":"Why do some crows seem to point at things with their beak?"},{"id":"crow-tool-use","t":"nature","q":"Why can a crow bend a straight piece of wire into a hook to solve a puzzle?"},{"id":"crowded-vs-lone-tree-shape","t":"nature","q":"Why do trees in a crowded forest grow tall and thin while a lone tree in a paddock grows short and wide?"},{"id":"cuckoo-egg-swap","t":"nature","q":"Why does a cuckoo chick push its foster siblings' eggs out of the nest?"},{"id":"cuckoo-solo-migration-innate","t":"nature","q":"Why can a young cuckoo fly to Africa alone without ever meeting its parents?"},{"id":"cuttlefish-colourblind-camouflage","t":"nature","q":"Why can a cuttlefish match colours perfectly when its eyes can't see colour?"},{"id":"cuttlefish-two-sided-display","t":"nature","q":"Why can a cuttlefish flash two completely different colour patterns at once?"},{"id":"daddy-long-legs-myth","t":"nature","q":"Why do people say daddy long-legs are the most venomous spider in the world?"},{"id":"daisy-composite-flower","t":"nature","q":"Why does a daisy's yellow middle look completely different from its white 'petals'?"},{"id":"dartfrog-tadpole-carry","t":"nature","q":"Why does a poison dart frog father carry his tadpoles piggyback through the forest?"},{"id":"darwin-orchid-moth-prediction","t":"nature","q":"Why did a scientist predict a moth nobody had ever seen, just from a flower?"},{"id":"deceptive-orchid-no-nectar","t":"nature","q":"Why do so many orchids trick insects into visiting for nothing at all?"},{"id":"decorator-crab-disguise","t":"nature","q":"Why do some crabs glue seaweed and sponges onto their own shells?"},{"id":"deepsea-fish-tube-eyes","t":"nature","q":"Why do many deep-sea fish have huge, tube-shaped eyes pointing straight up?"},{"id":"deer-fawn-freeze-instinct","t":"nature","q":"Why does a fawn freeze completely still instead of running when something gets close?"},{"id":"deer-scent-marking-territory","t":"nature","q":"Why do deer mark trees with scent instead of calling out?"},{"id":"desert-ant-polarised-light","t":"nature","q":"Why can a desert ant walk home in an almost dead-straight line across featureless sand?"},{"id":"desert-seed-mucilage-anchor","t":"nature","q":"Why does a wet desert seed sometimes wrap itself in slime the moment it rains?"},{"id":"desert-tortoise-estivation-burrow","t":"nature","q":"Why does a desert tortoise spend most of its life underground instead of in the sun?"},{"id":"desertant-path-integration","t":"nature","q":"Why can a desert ant walk home in a straight line after a wandering search for food?"},{"id":"devil-bite-force","t":"nature","q":"Why does a Tasmanian devil have such a powerful bite for its size?"},{"id":"devil-cartoon-myth","t":"nature","q":"Why is the cartoon Tasmanian devil so different from the real animal?"},{"id":"devil-screech","t":"nature","q":"Why do Tasmanian devils scream and screech at each other?"},{"id":"digitigrade-toe-walking","t":"nature","q":"Why do cats and dogs always walk on their toes?"},{"id":"dingo-howl-not-bark","t":"nature","q":"Why do dingoes howl so much but almost never bark like a pet dog?"},{"id":"dingo-not-pet-dog","t":"nature","q":"Why are dingoes considered different from pet dogs?"},{"id":"diving-beetle-air-bubble","t":"nature","q":"Why can a diving beetle carry its own air bubble underwater like a tiny tank?"},{"id":"dog-guilty-look-myth","t":"nature","q":"Why doesn't a dog's 'guilty look' actually mean it feels guilty?"},{"id":"dogs-circle","t":"nature","q":"Why do dogs circle before lying down?"},{"id":"dogs-colour","t":"nature","q":"Why aren't dogs actually colourblind?"},{"id":"dogs-pant","t":"nature","q":"Why do dogs pant instead of sweat?"},{"id":"dogs-puppyteeth","t":"nature","q":"Why are puppy teeth so needle-sharp?"},{"id":"dogs-sniff","t":"nature","q":"Why do dogs sniff everything?"},{"id":"dogs-tilt","t":"nature","q":"Why do dogs tilt their heads at you?"},{"id":"dogs-wag","t":"nature","q":"Why doesn't a wagging tail always mean a happy dog?"},{"id":"dogs-wetnose","t":"nature","q":"Why are dogs' noses wet?"},{"id":"dogs-zoomies","t":"nature","q":"Why do dogs get sudden bursts of crazy energy?"},{"id":"dolphin-echolocation","t":"nature","q":"Why do dolphins click and whistle to \"see\" underwater?"},{"id":"dolphin-signature-whistles","t":"nature","q":"Why does each dolphin seem to have its own name?"},{"id":"dolphin-swim-tail-fluke","t":"nature","q":"Why does a dolphin's tail move up and down when it swims, instead of side to side like a fish's?"},{"id":"dormouse-name-sleep","t":"nature","q":"Why does the dormouse have \"sleep\" hidden in its very name?"},{"id":"dragonfly-giant-eyes","t":"nature","q":"Why do dragonflies have such enormous eyes?"},{"id":"dragonfly-globe-skimmer-ocean","t":"nature","q":"Why can a dragonfly cross an entire ocean that no dragonfly has ever seen before?"},{"id":"dragonfly-hover-backwards","t":"nature","q":"Why can dragonflies fly backwards and hang perfectly still in the air?"},{"id":"dragonfly-underwater-life","t":"nature","q":"Why do dragonflies spend most of their life underwater?"},{"id":"drop-bear-myth","t":"nature","q":"Why do Australians tell tourists that \"drop bears\" will fall out of trees and attack?"},{"id":"drought-early-leaf-drop","t":"nature","q":"Why do some trees drop their leaves early during a bad drought, even in the middle of summer?"},{"id":"duck-feet-mud-seeds","t":"nature","q":"Why can a brand-new pond fill up with plants nobody planted there?"},{"id":"duck-mallard-ancestor","t":"nature","q":"Why do so many different-looking ducks come from the same wild bird?"},{"id":"duck-quack-echo","t":"nature","q":"Why don't people believe a duck's quack echoes?"},{"id":"duck-waddle-pelvis","t":"nature","q":"Why do ducks waddle from side to side instead of walking smoothly?"},{"id":"duck-waterproof","t":"nature","q":"Why does water roll off a duck's back?"},{"id":"duck-webbed-feet","t":"nature","q":"Why do ducks have webbed feet?"},{"id":"duckling-imprinting","t":"nature","q":"Why do ducklings follow the very first moving thing they see after hatching?"},{"id":"dugong-mermaid-myth","t":"nature","q":"Why did sailors mistake dugongs for mermaids?"},{"id":"dugong-seagrass-grazing","t":"nature","q":"Why do dugongs need to eat seagrass meadows almost all day long?"},{"id":"dung-beetle-stars","t":"nature","q":"Why do some dung beetles look up at the Milky Way while they work?"},{"id":"dungbeetle-milkyway-steering","t":"nature","q":"Why can a dung beetle roll its ball in a straight line by looking at the Milky Way?"},{"id":"dwarf-lemur-only-primate-hibernator","t":"nature","q":"Why is one kind of lemur the only primate known to truly hibernate?"},{"id":"earthworm-peristalsis-move","t":"nature","q":"Why can an earthworm burrow through soil with no legs and no eyes at all?"},{"id":"earwig-mother-care","t":"nature","q":"Why does a mother earwig guard her eggs and babies when almost no other insect bothers?"},{"id":"echidna-curl-spines","t":"nature","q":"Why do echidnas curl into a ball of spines instead of running away?"},{"id":"echidna-egg-pouch","t":"nature","q":"Why does an echidna carry its egg in a temporary pouch?"},{"id":"echidna-electric-snout","t":"nature","q":"Why does an echidna's snout sense electricity from prey?"},{"id":"echidna-fast-tongue","t":"nature","q":"Why can an echidna's tongue flick out so fast to catch ants?"},{"id":"echidna-hibernate-cold-climates","t":"nature","q":"Why do echidnas in cold parts of Australia hibernate while ones in warm areas don't?"},{"id":"eel-leaf-larvae-drift","t":"nature","q":"Why do baby eels look like clear glass leaves instead of tiny eels?"},{"id":"eel-overland-slither-rain","t":"nature","q":"Why can eels slither overland between ponds on rainy nights?"},{"id":"eel-sargasso-sea-birth","t":"nature","q":"Why do European eels swim 6,000 kilometres to a single patch of ocean to be born?"},{"id":"egg-camouflage","t":"nature","q":"Why are some birds' eggs covered in speckles while others are plain white?"},{"id":"egg-shape-pointy","t":"nature","q":"Why are some bird eggs almost round while others are sharply pointed at one end?"},{"id":"eggshell-strength","t":"nature","q":"Why is an eggshell strong enough to sit on, but easy for a chick to break out of?"},{"id":"electric-eel-defence-shock","t":"nature","q":"Why can an electric eel shock something without ever touching it with its mouth?"},{"id":"electric-eel-electrolocation","t":"nature","q":"Why can an electric eel navigate through muddy water without bumping into anything?"},{"id":"electric-fish-pulse-talk","t":"nature","q":"Why do some fish 'talk' using electric pulses instead of sound?"},{"id":"elephant-allomothers","t":"nature","q":"Why do elephant calves get looked after by aunts as well as their mother?"},{"id":"elephant-calf-trunk","t":"nature","q":"Why does a baby elephant suck on its own trunk like a thumb?"},{"id":"elephant-cant-jump","t":"nature","q":"Why can't an elephant jump, even a little?"},{"id":"elephant-family-recognize-calls","t":"nature","q":"Why can an elephant recognise a relative's call after years apart?"},{"id":"elephant-infrasound-ground","t":"nature","q":"Why can elephants sense a rumble through their feet?"},{"id":"elephant-matriarch-memory-routes","t":"nature","q":"Why do elephant herds rely on their oldest female to find water in a drought?"},{"id":"elephant-seal-roar-recognition","t":"nature","q":"Why can a bull elephant seal tell a rival apart just by his roar?"},{"id":"elephant-seed-gut","t":"nature","q":"Why do some African trees need an elephant to make a baby tree?"},{"id":"elephant-seismic-feet","t":"nature","q":"Why can elephants \"hear\" a storm or another herd through their feet?"},{"id":"elephant-short-wild-sleep","t":"nature","q":"Why do wild elephants sometimes sleep for as little as two hours a day?"},{"id":"elephant-trunk-smell","t":"nature","q":"Why is an elephant's sense of smell better than a bloodhound's?"},{"id":"elephantseal-deep-eyes","t":"nature","q":"Why do elephant seals have huge eyes for diving into near-total darkness?"},{"id":"elephantseal-migration-routes","t":"nature","q":"Why do male and female elephant seals travel completely different migration routes?"},{"id":"emperor-penguin-march-breeding","t":"nature","q":"Why do emperor penguins walk for days across the ice instead of breeding near the sea?"},{"id":"emu-dad-duty","t":"nature","q":"Why do male emus do almost all the egg-sitting and chick-raising?"},{"id":"emu-wings","t":"nature","q":"Why do emus still have wings if they never use them to fly?"},{"id":"epicormic-regrowth","t":"nature","q":"Why can a blackened, burnt tree trunk sprout bright green leaves just weeks after a fire?"},{"id":"evergreen-needles-still-shed","t":"nature","q":"Why do evergreen trees still lose needles, just not all at once?"},{"id":"extrafloral-nectar-ants","t":"nature","q":"Why do some plants feed ants with nectar that isn't even inside the flower?"},{"id":"farm-animal-wild-look","t":"nature","q":"Why do farm animals look so different from their wild ancestors?"},{"id":"fat-tailed-dunnart-daily-torpor","t":"nature","q":"Why does a tiny marsupial called a dunnart go into torpor almost every single day?"},{"id":"fawn-left-alone","t":"nature","q":"Why does a mother deer leave her fawn alone for hours at a time?"},{"id":"feather-barbs","t":"nature","q":"Why don't a bird's flight feathers rip apart when it flies through branches?"},{"id":"feather-colour-structural","t":"nature","q":"Why can a feather look brilliant blue when it has no blue colouring in it at all?"},{"id":"feather-down","t":"nature","q":"Why do birds grow soft, fluffy down feathers hidden under their smooth outer ones?"},{"id":"feather-vane-shape","t":"nature","q":"Why is one side of a flight feather narrower than the other?"},{"id":"fiddler-crab-claw-wave","t":"nature","q":"Why does a male fiddler crab wave one giant claw around?"},{"id":"fig-strangler-bird-drop","t":"nature","q":"Why does a strangler fig often start life high up in the fork of another tree?"},{"id":"fig-wasp-mutualism","t":"nature","q":"Why does almost every kind of fig need its own particular kind of wasp?"},{"id":"fireflies-glow","t":"nature","q":"Why do fireflies light up?"},{"id":"firefly-synchronised-flashing","t":"nature","q":"Why do thousands of fireflies sometimes flash on and off at exactly the same moment?"},{"id":"fireweed-first-after-eruption","t":"nature","q":"Why was fireweed one of the very first plants to bloom after Mount St Helens erupted?"},{"id":"fish-lateral-line","t":"nature","q":"Why can a school of fish turn together in a fraction of a second without colliding?"},{"id":"fish-scale-gecko-skin-shed","t":"nature","q":"Why can a fish-scale gecko rip off its own skin the instant something grabs it?"},{"id":"fish-swimbladder-hearing","t":"nature","q":"Why can some fish hear far better than others?"},{"id":"flamingo-crop-milk","t":"nature","q":"Why do flamingo parents feed their chicks a bright red milk instead of fish?"},{"id":"flamingos-pink","t":"nature","q":"Why are flamingos pink?"},{"id":"flea-jump-resilin","t":"nature","q":"Why can a flea jump so much further than its tiny legs seem able to manage?"},{"id":"fledgling-ground-normal","t":"nature","q":"Why is it normal to find a young bird hopping on the ground, unable to fly yet?"},{"id":"flock-no-crash","t":"nature","q":"Why don't birds in a huge, fast-moving flock crash into each other?"},{"id":"flower-anther-timing-protandry","t":"nature","q":"Why do a flower's male and female parts sometimes ripen on completely different days?"},{"id":"flower-color-change-pollinated","t":"nature","q":"Why do some flowers change colour after they've already been pollinated?"},{"id":"flower-constancy-bee","t":"nature","q":"Why does one bee usually visit only one kind of flower on each trip out?"},{"id":"flower-nectar-guide-lines","t":"nature","q":"Why do some flowers have lines painted down the middle of each petal?"},{"id":"flower-night-closing","t":"nature","q":"Why do some flowers close up every single night?"},{"id":"flower-perfect-anatomy","t":"nature","q":"Why do most flowers have both male and female parts in the very same bloom?"},{"id":"flower-petal-fibonacci","t":"nature","q":"Why do so many flowers have petal counts like 3, 5, 8, 13 or 21, and hardly ever 4, 6 or 7?"},{"id":"flower-red-bird-pollinated","t":"nature","q":"Why are some flowers bright red with almost no smell at all?"},{"id":"flower-scent-changes-day","t":"nature","q":"Why can a flower smell different in the morning than at night?"},{"id":"flower-self-incompatibility","t":"nature","q":"Why can't some flowers use their own pollen even when it lands right on them?"},{"id":"flower-symmetry-signal","t":"nature","q":"Why do bees seem to prefer flowers with evenly matched petals?"},{"id":"flowers-smell","t":"nature","q":"Why do flowers smell nice?"},{"id":"fly-hard-to-swat","t":"nature","q":"Why are flies so hard to swat?"},{"id":"fly-leg-rubbing","t":"nature","q":"Why do flies keep rubbing their front legs together?"},{"id":"fly-vomit-food","t":"nature","q":"Why do flies land on food and seem to spit on it first?"},{"id":"flying-fish-glide-escape","t":"nature","q":"Why do flying fish burst out of the water and glide instead of just swimming faster?"},{"id":"flying-frog-glide","t":"nature","q":"Why can some tree frogs glide through the air between branches?"},{"id":"flying-snake-glide","t":"nature","q":"Why can some snakes glide through the air between trees?"},{"id":"flyinglizard-draco-glide","t":"nature","q":"Why can some small lizards spread ribs out like wings to glide between trees?"},{"id":"flytrap-flower-height","t":"nature","q":"Why does a Venus flytrap grow its flowers on a tall stalk far above its snapping traps?"},{"id":"foal-stand-fast","t":"nature","q":"Why can a newborn foal stand and run within hours of being born?"},{"id":"fox-kit-babysit","t":"nature","q":"Why do young female foxes sometimes stay home to help raise their mother's next litter?"},{"id":"fox-pounce-snow","t":"nature","q":"Why does a fox leap so high before pouncing into snow?"},{"id":"fox-tail-tip","t":"nature","q":"Why does a red fox have a bright white tip on the end of its tail?"},{"id":"frill-neck-lizard-frill","t":"nature","q":"Why does a startled lizard suddenly open a huge frill around its neck?"},{"id":"frilled-lizard-startle","t":"nature","q":"Why does an Australian frilled lizard suddenly open a huge collar around its neck?"},{"id":"frog-blink-swallow","t":"nature","q":"Why do frogs blink hard every time they swallow?"},{"id":"frog-breeding-temporary-pools","t":"nature","q":"Why do so many frogs suddenly start calling all at once after heavy rain?"},{"id":"frog-camouflage-skin","t":"nature","q":"Why do so many frogs match the exact colour of leaves, bark or mud around them?"},{"id":"frog-drink-through-skin","t":"nature","q":"Why don't frogs ever seem to drink water with their mouths?"},{"id":"frog-egg-jelly-coat","t":"nature","q":"Why are frog eggs always wrapped in a blob of clear jelly?"},{"id":"frog-eyes-on-top-of-head","t":"nature","q":"Why do a frog's eyes sit right on top of its head instead of the sides?"},{"id":"frog-jump-legs","t":"nature","q":"Why can a frog jump so many times its own body length?"},{"id":"frog-shed-skin-eat-it","t":"nature","q":"Why do frogs shed their skin, and where does the old skin go?"},{"id":"frog-skin-breathing","t":"nature","q":"Why do frogs breathe through their skin as well as their lungs?"},{"id":"frog-species-specific-call","t":"nature","q":"Why do dozens of different frog species calling at the same pond never seem to confuse each other?"},{"id":"frog-sticky-tongue","t":"nature","q":"Why can a frog's tongue snatch an insect faster than you can blink?"},{"id":"frog-toad-difference","t":"nature","q":"Why do frogs have smooth skin while toads look dry and bumpy?"},{"id":"frog-vocal-sac","t":"nature","q":"Why do some frogs blow up a balloon under their chin when they call?"},{"id":"frogfish-walk-fins","t":"nature","q":"Why does a frogfish seem to walk along the seafloor instead of swimming?"},{"id":"froghopper-best-jumper","t":"nature","q":"Why is a tiny froghopper insect a better jumper than a flea?"},{"id":"frogs-croak","t":"nature","q":"Why do frogs croak?"},{"id":"funnel-web-dangerous","t":"nature","q":"Why is the Sydney funnel-web spider's bite treated as a real emergency?"},{"id":"furseal-bimodal-sleep-water-land","t":"nature","q":"Why does a fur seal sleep differently in water than it does on land?"},{"id":"gartersnake-mass-hibernaculum","t":"nature","q":"Why do thousands of garter snakes hibernate coiled together in a single den?"},{"id":"gecko-lose-grip-water","t":"nature","q":"Why do geckos slip and slide on wet glass?"},{"id":"gecko-night-colour-vision","t":"nature","q":"Why can a gecko see colour on a night so dark that our eyes see nothing at all?"},{"id":"gecko-sticky-feet","t":"nature","q":"Why can geckos run straight up glass?"},{"id":"geese-v-formation","t":"nature","q":"Why do geese fly in a V shape on a long migration?"},{"id":"gibbon-brachiation-swing","t":"nature","q":"Why do gibbons swing hand over hand through trees instead of climbing along branches?"},{"id":"gibbon-duet-song","t":"nature","q":"Why do gibbon pairs sing loud duets together each morning?"},{"id":"gila-monster-venomous-lizard","t":"nature","q":"Why is the Gila monster one of the only venomous lizards?"},{"id":"giraffe-calf-blotch-camouflage","t":"nature","q":"Why do newborn giraffe calves have blotchy patterns instead of plain colouring?"},{"id":"giraffe-calf-fall","t":"nature","q":"Why does a newborn giraffe fall almost two metres to the ground the moment it's born?"},{"id":"giraffe-night-humming","t":"nature","q":"Why do giraffes seem to hum quietly to each other at night?"},{"id":"giraffe-short-bursts-sleep","t":"nature","q":"Why does a giraffe sometimes sleep for less than 30 minutes across a whole day?"},{"id":"glass-frog-see-through-belly","t":"nature","q":"Why can you see a glass frog's beating heart through its own skin?"},{"id":"goanna-climb-mistake","t":"nature","q":"Why do goannas sometimes climb up a person who startles them?"},{"id":"goat-beard","t":"nature","q":"Why do some goats have beards?"},{"id":"goat-cashmere-mohair","t":"nature","q":"Why is cashmere so much softer than a goat's usual coat?"},{"id":"goat-eyes-rectangle","t":"nature","q":"Why do goats have such strange, rectangular eyes?"},{"id":"goat-stand-hind-legs","t":"nature","q":"Why do goats stand on their hind legs to eat?"},{"id":"goat-tin-cans","t":"nature","q":"Why do people say goats will eat a tin can?"},{"id":"godwit-nonstop-flight","t":"nature","q":"Why can a bar-tailed godwit fly for eleven days without ever landing?"},{"id":"golden-mole-sand-swim","t":"nature","q":"Why does a golden mole seem to swim through sand instead of digging tunnels?"},{"id":"goldfish-colourchange","t":"nature","q":"Why are baby goldfish often dark grey instead of gold?"},{"id":"goldfish-eyelids","t":"nature","q":"Why do goldfish sleep with their eyes wide open?"},{"id":"goldfish-gulp","t":"nature","q":"Why do goldfish gulp at the surface of the water?"},{"id":"goldfish-ice","t":"nature","q":"Why don't pond goldfish freeze to death in winter?"},{"id":"gorilla-sign-language-myth","t":"nature","q":"Why is the story of a gorilla who 'spoke' sign language more complicated than it sounds?"},{"id":"gorse-pod-crackle","t":"nature","q":"Why do gorse bushes crackle and pop on a hot day?"},{"id":"grass-seed-wind-gust-release","t":"nature","q":"Why do grass seed heads only let go of their seeds in a strong gust, not a gentle breeze?"},{"id":"grasshopper-jump","t":"nature","q":"Why can grasshoppers jump so many times their own body length?"},{"id":"grasshopper-song-legs","t":"nature","q":"Why do grasshoppers make music by rubbing their legs?"},{"id":"greywhale-longest-migration","t":"nature","q":"Why does the grey whale make the longest migration of any mammal on Earth?"},{"id":"grizzly-hump","t":"nature","q":"Why does a grizzly bear have a hump of muscle on its shoulders?"},{"id":"groundhog-hibernation-myth","t":"nature","q":"Why can't a groundhog actually predict how long winter will last?"},{"id":"groundsquirrel-true-hibernator","t":"nature","q":"Why is a ground squirrel a true hibernator when a bear isn't?"},{"id":"guinea-freeze","t":"nature","q":"Why do guinea pigs freeze completely still when scared?"},{"id":"guinea-notail","t":"nature","q":"Why don't guinea pigs seem to have a tail?"},{"id":"guinea-popcorn","t":"nature","q":"Why do guinea pigs suddenly jump straight up in the air?"},{"id":"guinea-vitaminc","t":"nature","q":"Why do guinea pigs need vitamin C in their food every day?"},{"id":"guinea-wheek","t":"nature","q":"Why do guinea pigs squeal the moment they hear a fridge door?"},{"id":"gut-passage-germination-boost","t":"nature","q":"Why do some seeds actually grow better after passing straight through an animal's gut?"},{"id":"hairstreak-false-head","t":"nature","q":"Why do some small butterflies have thin tails and fake antennae at the wrong end?"},{"id":"hairy-frog-bone-claws","t":"nature","q":"Why does a hairy frog break its own toe bones to make claws?"},{"id":"hamsters-cheeks","t":"nature","q":"Why do hamsters stuff their cheeks so full?"},{"id":"hamsters-hoard","t":"nature","q":"Why do hamsters hide food even when their bowl is already full?"},{"id":"hamsters-nocturnal","t":"nature","q":"Why do hamsters sleep through most of the day?"},{"id":"hamsters-solitary","t":"nature","q":"Why can't most pet hamsters share a cage?"},{"id":"hamsters-wheel","t":"nature","q":"Why do hamsters run for miles on their wheel every night?"},{"id":"hedgehog-hibernation-nest","t":"nature","q":"Why does a hedgehog build a special nest before it hibernates?"},{"id":"hedgehog-spine-curl","t":"nature","q":"Why does a hedgehog curl into a tight, spiky ball instead of running away?"},{"id":"hellbender-skin-folds","t":"nature","q":"Why does a hellbender salamander have such loose, wrinkly folds of skin?"},{"id":"herring-bubble-communication","t":"nature","q":"Why do herring 'talk' to each other by releasing bubbles?"},{"id":"hibernation-waking-costs-energy","t":"nature","q":"Why is waking up the most dangerous part of hibernation for an animal?"},{"id":"hibernator-brown-fat-rewarming","t":"nature","q":"Why can a hibernating animal warm itself back up so fast without shivering at all?"},{"id":"hognose-snake-play-dead","t":"nature","q":"Why does a hognose snake flip onto its back and pretend to be dead?"},{"id":"hollow-tree-still-alive","t":"nature","q":"Why can a tree stay perfectly healthy even after its trunk goes completely hollow inside?"},{"id":"honeybadger-fearless","t":"nature","q":"Why does a honey badger attack animals many times its own size without any fear?"},{"id":"honeybee-waggle-dance-direction","t":"nature","q":"Why does a honeybee dance in a figure-eight to tell the hive where the flowers are?"},{"id":"honeybee-winter-cluster-shiver","t":"nature","q":"Why do honeybees form a tight, shivering ball instead of hibernating through winter?"},{"id":"hoof-split","t":"nature","q":"Why do cows, sheep, goats and pigs have split hooves?"},{"id":"horned-lizard-squirt-blood","t":"nature","q":"Why can some lizards squirt blood out of their own eyes?"},{"id":"horse-ears-swivel","t":"nature","q":"Why can horses swivel their ears almost all the way around?"},{"id":"horse-eyes-side","t":"nature","q":"Why are a horse's eyes on the sides of its head?"},{"id":"horse-hoof-grows","t":"nature","q":"Why do horses need horseshoes?"},{"id":"horse-sleep-standing","t":"nature","q":"Why can horses sleep standing up?"},{"id":"horse-teeth-age","t":"nature","q":"Why can you tell how old a horse is from its teeth?"},{"id":"horse-unguligrade-toe-walk","t":"nature","q":"Why does a horse walk balanced on what is really just one toe?"},{"id":"horse-whinny","t":"nature","q":"Why do horses whinny?"},{"id":"house-centipede-speed","t":"nature","q":"Why does the house centipede run so fast on so many long legs?"},{"id":"hoverfly-wasp-mimicry","t":"nature","q":"Why do some flies that visit flowers look like they could sting you?"},{"id":"hummingbird-gulf-nonstop-flight","t":"nature","q":"Why can a hummingbird the size of your thumb cross the Gulf of Mexico without stopping?"},{"id":"hummingbird-hover-backwards","t":"nature","q":"Why can hummingbirds hover in place and even fly backwards?"},{"id":"hummingbird-nightly-torpor","t":"nature","q":"Why does a hummingbird sometimes look dead each morning before it wakes up?"},{"id":"humpback-migration-no-eating","t":"nature","q":"Why do humpback whales go months without eating during their migration?"},{"id":"humpback-whale-song-culture","t":"nature","q":"Why does a whole population of humpback whales change its song together?"},{"id":"huntsman-harmless","t":"nature","q":"Why is a huge huntsman spider almost never dangerous?"},{"id":"hyena-hunter-not-scavenger","t":"nature","q":"Why do spotted hyenas have a reputation as scavengers when they actually hunt most of their own food?"},{"id":"hyena-jaw-bone-crush","t":"nature","q":"Why can a hyena crunch straight through bone that most predators leave behind?"},{"id":"hyena-laugh","t":"nature","q":"Why does a hyena make a sound like laughing?"},{"id":"ibis-bill-touch","t":"nature","q":"Why can a wading bird find a worm buried in mud without seeing or hearing it?"},{"id":"inchworm-loop-move","t":"nature","q":"Why do inchworms move by looping their bodies up into an arch?"},{"id":"indigo-bunting-star-compass","t":"nature","q":"Why did scientists build a fake sky in a planetarium to study a small blue bird?"},{"id":"insect-moulting","t":"nature","q":"Why do insects have to burst out of their own skin to grow?"},{"id":"insect-size-limit","t":"nature","q":"Why can't insects grow as big as a cat?"},{"id":"insects-hold-up-world","t":"nature","q":"Why would most life on Earth struggle to survive without insects?"},{"id":"insects-natures-recyclers","t":"nature","q":"Why do dead leaves and fallen branches disappear from a forest floor so quickly?"},{"id":"island-bird-dropping-plants","t":"nature","q":"Why do plants that don't grow anywhere nearby suddenly appear on a remote island?"},{"id":"jaguar-bite-force","t":"nature","q":"Why does a jaguar have the strongest bite of any big cat its size?"},{"id":"jaguar-skull-bite","t":"nature","q":"Why does a jaguar bite through the skull instead of the throat like a lion?"},{"id":"jaguar-swim","t":"nature","q":"Why are jaguars such confident swimmers when most big cats stay dry?"},{"id":"jay-oak-planting","t":"nature","q":"Why is a jay one of an oak tree's best friends?"},{"id":"jellyfish-pulse-swim","t":"nature","q":"Why does a jellyfish pulse its whole body instead of swimming with fins or legs?"},{"id":"joey-leaves-pouch","t":"nature","q":"Why does a kangaroo joey keep poking its head out of the pouch months before it fully leaves?"},{"id":"joey-pouch-clean","t":"nature","q":"Why does a mother kangaroo clean out her own pouch with her tongue?"},{"id":"judean-date-palm-ancient-seed","t":"nature","q":"Why did a 2,000-year-old seed suddenly grow into a tree?"},{"id":"jumping-spider-eyes","t":"nature","q":"Why do jumping spiders have eight eyes but only really see with two?"},{"id":"jumpingspider-hydraulic-legs","t":"nature","q":"Why can a jumping spider leap many times its own body length without huge leg muscles?"},{"id":"jumpingspider-rem-like-twitch-sleep","t":"nature","q":"Why do baby jumping spiders twitch their legs and flutter their eye tubes while resting at night?"},{"id":"kangaroo-boxing","t":"nature","q":"Why do kangaroos \"box\" each other?"},{"id":"kangaroo-hop-tendons","t":"nature","q":"Why do kangaroos hop instead of running on four legs?"},{"id":"kangaroo-joey-size","t":"nature","q":"Why is a newborn kangaroo joey about the size of a jellybean?"},{"id":"kangaroo-no-backwards","t":"nature","q":"Why can't kangaroos walk backwards?"},{"id":"kangaroo-paused-pregnancy","t":"nature","q":"Why can a mother kangaroo pause a pregnancy for months without harm?"},{"id":"kangaroo-tail-leg","t":"nature","q":"Why do scientists call a kangaroo's tail its \"fifth leg\"?"},{"id":"katydid-flash-wings","t":"nature","q":"Why do some plain brown katydids suddenly flash bright colours when a bird gets close?"},{"id":"killdeer-broken-wing-act","t":"nature","q":"Why does a killdeer bird drag its wing like it's broken when a predator nears its nest?"},{"id":"king-cobra-nest-builder","t":"nature","q":"Why is the king cobra the only snake that builds an actual nest?"},{"id":"kitten-blind-deaf","t":"nature","q":"Why are kittens born with their eyes and ears completely sealed shut?"},{"id":"kiwi-nostril-smell","t":"nature","q":"Why does a kiwi bird have nostrils right at the very tip of its long beak?"},{"id":"koala-deep-bellow","t":"nature","q":"Why does a koala's bellow sound far too deep for such a small animal?"},{"id":"koala-drunk-myth","t":"nature","q":"Why do people think koalas are drunk on eucalyptus, and is that true?"},{"id":"koala-fingerprints","t":"nature","q":"Why are koala fingerprints almost identical to human ones?"},{"id":"koala-joey-pap","t":"nature","q":"Why does a baby koala eat a special substance from its mother before it can chew leaves?"},{"id":"koala-not-bear","t":"nature","q":"Why are koalas not actually bears?"},{"id":"koala-sleep","t":"nature","q":"Why do koalas sleep up to 20 hours a day?"},{"id":"koala-toxic-diet","t":"nature","q":"Why can koalas eat gum leaves that would poison most other animals?"},{"id":"koala-two-thumbs","t":"nature","q":"Why do koalas have two thumbs on each front paw?"},{"id":"komodo-dragon-venom","t":"nature","q":"Why is a Komodo dragon's bite so dangerous, even after it lets go?"},{"id":"kookaburra-laugh","t":"nature","q":"Why does a kookaburra's call sound so much like human laughter?"},{"id":"lady-slipper-orchid-trap","t":"nature","q":"Why does the lady's slipper orchid force insects to climb out through a one-way exit?"},{"id":"ladybird-mass-overwintering-clusters","t":"nature","q":"Why do ladybirds pile up together in huge clusters to spend the winter?"},{"id":"ladybird-play-dead","t":"nature","q":"Why do ladybirds leak yellow goo and flop over when you pick them up?"},{"id":"ladybird-warning-colours","t":"nature","q":"Why are ladybirds so brightly coloured with spots?"},{"id":"lamb-find-mother","t":"nature","q":"Why can a lamb find its mother in a flock of hundreds?"},{"id":"leaf-insect-vein-mimicry","t":"nature","q":"Why do some insects have fake leaf veins and even fake bite marks on their wings?"},{"id":"leaf-tailed-gecko-bark","t":"nature","q":"Why can a leaf-tailed gecko practically disappear against a tree trunk?"},{"id":"leafcutter-ant-alarm-pheromone","t":"nature","q":"Why does one squashed ant send its whole colony into a defensive frenzy?"},{"id":"leatherback-turtle-migration-jellyfish","t":"nature","q":"Why does the leatherback turtle cross entire oceans chasing jellyfish?"},{"id":"leaves-abscission-layer","t":"nature","q":"Why doesn't a falling leaf leave an open wound on the branch?"},{"id":"leaves-autumn-colours-hidden","t":"nature","q":"Why do leaves turn yellow and orange in autumn?"},{"id":"leaves-autumn-red-new-pigment","t":"nature","q":"Why do some leaves turn bright red in autumn instead of just yellow?"},{"id":"leaves-breathe-at-night","t":"nature","q":"Why do plants breathe in oxygen at night if they make it during the day?"},{"id":"leaves-brown-tannins","t":"nature","q":"Why do some leaves just turn plain brown in autumn, without any red or orange?"},{"id":"leaves-c3-vs-desert","t":"nature","q":"Why do some desert plants only open their leaf pores at night?"},{"id":"leaves-carbon-dioxide-limit","t":"nature","q":"Why can't plants make food faster just by giving them more sunlight?"},{"id":"leaves-chlorophyll-breaks-down-fast","t":"nature","q":"Why do cut flower leaves and lettuce in the fridge go yellow within days?"},{"id":"leaves-chlorophyll-needs-magnesium","t":"nature","q":"Why does a chlorophyll molecule need a tiny bit of metal buried in the middle of it?"},{"id":"leaves-chlorophyll-two-pigments","t":"nature","q":"Why isn't there just one kind of chlorophyll in a leaf?"},{"id":"leaves-compound-vs-simple","t":"nature","q":"Why do some trees have one big leaf shape while others have leaves split into lots of little leaflets?"},{"id":"leaves-crunch-when-dry","t":"nature","q":"Why do dead autumn leaves crunch so loudly when you step on them, but fresh green leaves don't?"},{"id":"leaves-eaten-regrow-nutrients","t":"nature","q":"Why can a plant afford to keep growing new leaves after insects chew through the old ones?"},{"id":"leaves-etiolation-no-light","t":"nature","q":"Why does a seedling grown in a dark cupboard turn pale and stretch out long and thin?"},{"id":"leaves-evergreen-vs-deciduous","t":"nature","q":"Why do pine trees keep their leaves all winter while oak trees drop theirs?"},{"id":"leaves-fall","t":"nature","q":"Why do trees lose their leaves?"},{"id":"leaves-fold-at-night","t":"nature","q":"Why do some plants fold their leaves up at night?"},{"id":"leaves-food-travels-both-ways","t":"nature","q":"Why can sugar from a leaf travel down to feed the roots, when the roots are nowhere near the sunlight?"},{"id":"leaves-green","t":"nature","q":"Why are leaves green?"},{"id":"leaves-guard-cells-open-close","t":"nature","q":"Why do the pores on a leaf open and close instead of staying open all the time?"},{"id":"leaves-light-saturation","t":"nature","q":"Why doesn't a leaf make more and more food the brighter the sunlight gets?"},{"id":"leaves-lose-colour-when-sick","t":"nature","q":"Why do a plant's leaves turn pale or yellow when it isn't getting enough of certain nutrients?"},{"id":"leaves-moss-no-true-leaves","t":"nature","q":"Why do moss leaves look and feel completely different from a tree's leaves?"},{"id":"leaves-need-cool-nights-sugar-storage","t":"nature","q":"Why do the best autumn leaf colours often follow a run of warm sunny days and cool nights?"},{"id":"leaves-not-for-us","t":"nature","q":"Why do plants make oxygen?"},{"id":"leaves-not-lungs-myth","t":"nature","q":"Why is it wrong to call a leaf's pores the plant's version of lungs?"},{"id":"leaves-not-only-green","t":"nature","q":"Why are some plants' leaves purple or red all year round, not just in autumn?"},{"id":"leaves-not-solar-panels-exactly","t":"nature","q":"Why are leaves nowhere near as efficient at using sunlight as a solar panel?"},{"id":"leaves-oxygen-not-always-there","t":"nature","q":"Why wasn't there always oxygen in Earth's air for animals to breathe?"},{"id":"leaves-palisade-layer","t":"nature","q":"Why is the top of a leaf usually greener than the bottom?"},{"id":"leaves-photosynthesis-equation-simplified","t":"nature","q":"Why do scientists say photosynthesis turns carbon dioxide and water into sugar and oxygen, when it's really dozens of steps?"},{"id":"leaves-photosynthesis-invented-once","t":"nature","q":"Why do almost all plants use the exact same green chemical to make food from light?"},{"id":"leaves-photosynthesis-slows-cold","t":"nature","q":"Why do plants grow so much slower in winter even if their leaves stay green?"},{"id":"leaves-red-cabbage-not-chlorophyll","t":"nature","q":"Why is red cabbage red inside instead of green like most vegetable leaves?"},{"id":"leaves-shade-vs-sun","t":"nature","q":"Why are leaves at the top of a tree often thicker than leaves lower down?"},{"id":"leaves-shape-drip-tip","t":"nature","q":"Why do many rainforest leaves have a long pointy tip hanging off the end?"},{"id":"leaves-shed-water-not-just-drought","t":"nature","q":"Why do some trees drop a portion of their leaves even during an ordinary, non-drought summer?"},{"id":"leaves-splitting-water","t":"nature","q":"Why do leaves need water if sunlight is what makes their food?"},{"id":"leaves-stomata-pores","t":"nature","q":"Why does the underside of a leaf feel different from the top?"},{"id":"leaves-succulent-store-water","t":"nature","q":"Why are succulent leaves so thick and fleshy compared with an ordinary plant's leaves?"},{"id":"leaves-sunflower-tracking","t":"nature","q":"Why do young sunflower leaves and flower heads follow the sun across the sky?"},{"id":"leaves-thin-flat-shape","t":"nature","q":"Why are most leaves thin and flat instead of round or thick like a fruit?"},{"id":"leaves-touch-sensitive-mimosa","t":"nature","q":"Why do the leaves of some plants snap shut the instant you touch them?"},{"id":"leaves-toward-light-auxin","t":"nature","q":"Why do houseplants on a windowsill lean toward the window?"},{"id":"leaves-variegated-white-patches","t":"nature","q":"Why do some houseplant leaves have white or pale patches instead of being fully green?"},{"id":"leaves-veins-plumbing","t":"nature","q":"Why do leaves have all those thin lines running through them?"},{"id":"leaves-waxy-cuticle","t":"nature","q":"Why does rain bead up and roll off some leaves instead of soaking in?"},{"id":"legless-lizard-vs-snake","t":"nature","q":"Why do some legless lizards get mistaken for snakes?"},{"id":"leopard-rosettes","t":"nature","q":"Why are a leopard's spots shaped like little flowers instead of solid dots?"},{"id":"leopard-tree-drag","t":"nature","q":"Why do leopards drag their kills up into trees?"},{"id":"lightning-strikes-tall-trees","t":"nature","q":"Why do tall, lone trees get struck by lightning so often?"},{"id":"lion-cub-hidden","t":"nature","q":"Why does a lioness hide her newborn cubs away from the rest of the pride for weeks?"},{"id":"lion-lioness-hunt","t":"nature","q":"Why do lionesses do almost all of a pride's hunting?"},{"id":"lion-mane","t":"nature","q":"Why do male lions grow such a big, shaggy mane?"},{"id":"lion-roar-distance","t":"nature","q":"Why can a lion's roar be heard from so far away?"},{"id":"lion-savanna","t":"nature","q":"Why don't lions actually live in the jungle?"},{"id":"lizard-tail","t":"nature","q":"Why do lizards drop their tails?"},{"id":"lizard-tail-autotomy","t":"nature","q":"Why does a dropped lizard tail keep wiggling on the ground by itself?"},{"id":"lizard-third-eye","t":"nature","q":"Why do some lizards have a third eye on top of their head?"},{"id":"locust-swarm-downwind-migration","t":"nature","q":"Why do desert locusts suddenly form swarms and travel enormous distances together?"},{"id":"loggerhead-atlantic-gyre-journey","t":"nature","q":"Why do baby loggerhead turtles ride a giant circular current for years before coming back?"},{"id":"loudest-cicada-australia","t":"nature","q":"Why is an Australian cicada considered the loudest insect in the world?"},{"id":"lungfish-mud-cocoon-drought","t":"nature","q":"Why can a lungfish survive being buried in dried mud for years without water?"},{"id":"lungless-salamander","t":"nature","q":"Why do some salamanders have no lungs at all?"},{"id":"lupin-pod-twist-pop","t":"nature","q":"Why do pea and lupin pods twist and spring open as they dry?"},{"id":"lyrebird-mimicry","t":"nature","q":"Why can a lyrebird copy sounds like a chainsaw or a camera shutter so exactly?"},{"id":"magpie-lark-duet-one-voice","t":"nature","q":"Why can a magpie-lark pair's duet sound like just one bird singing?"},{"id":"magpie-swooping","t":"nature","q":"Why do magpies swoop people during spring but leave them alone the rest of the year?"},{"id":"manakin-wing-snap-courtship","t":"nature","q":"Why does a manakin bird make snapping sounds with its wings instead of singing?"},{"id":"manatee-body-whiskers","t":"nature","q":"Why is a manatee's entire body covered in short, stiff hairs?"},{"id":"manatee-contact-squeaks","t":"nature","q":"Why do manatee mothers and calves squeak constantly to stay in touch?"},{"id":"mangrove-breathing-roots","t":"nature","q":"Why do mangrove trees grow roots that stick up out of the mud?"},{"id":"mangrove-seed-sprout-parent","t":"nature","q":"Why does a mangrove seed start growing while it's still hanging on its parent tree?"},{"id":"mantaray-wing-swim","t":"nature","q":"Why does a manta ray seem to fly through the water rather than swim?"},{"id":"mantis-egg-case-overwinter-strategy","t":"nature","q":"Why does a praying mantis survive winter as an egg case instead of as an adult?"},{"id":"mantis-one-ear","t":"nature","q":"Why does a praying mantis have just one ear, right in the middle of its chest?"},{"id":"mantis-shrimp-colour-myth","t":"nature","q":"Why don't mantis shrimp see far more colours than us, despite having more colour receptors?"},{"id":"maple-syrup-early-spring","t":"nature","q":"Why do people tap maple trees for syrup only in early spring?"},{"id":"marmot-alpine-family-hibernation","t":"nature","q":"Why do alpine marmots hibernate huddled together in family groups?"},{"id":"meerkat-pup-babysit","t":"nature","q":"Why do meerkat pups get looked after by babysitters that aren't their parents?"},{"id":"meerkat-sentinel-urgency","t":"nature","q":"Why does a meerkat sentinel's call change with how close danger is?"},{"id":"metamorphosis-complete-incomplete","t":"nature","q":"Why do baby grasshoppers look like tiny grasshoppers, while baby flies look nothing like flies?"},{"id":"metamorphosis-why-bother","t":"nature","q":"Why do so many insects bother changing shape completely instead of just growing bigger?"},{"id":"midwife-toad-dad-carries-eggs","t":"nature","q":"Why does a male midwife toad wrap strings of eggs around his own back legs?"},{"id":"milk-white","t":"nature","q":"Why is cow's milk white?"},{"id":"milkweed-silk-lifejacket","t":"nature","q":"Why did people once stuff life jackets with fluff picked from wild milkweed pods?"},{"id":"millipede-coil-toxin","t":"nature","q":"Why do millipedes curl into a tight spiral the instant you touch them?"},{"id":"millipede-curl-defence","t":"nature","q":"Why do millipedes curl into a tight spiral when they're scared?"},{"id":"millipede-cyanide-smell","t":"nature","q":"Why do some millipedes smell like almonds when you pick them up?"},{"id":"millipede-leg-wave","t":"nature","q":"Why don't millipedes trip over their own hundreds of legs?"},{"id":"millipede-legs-record","t":"nature","q":"Why don't millipedes actually have a thousand legs, and which one finally did?"},{"id":"millipede-two-legs-segment","t":"nature","q":"Why do millipedes have two pairs of legs on every body segment instead of one?"},{"id":"mimic-octopus-impersonate","t":"nature","q":"Why can one octopus impersonate several completely different sea animals?"},{"id":"mistletoe-sticky-shot","t":"nature","q":"Why does mistletoe fire its seeds at neighbouring branches?"},{"id":"mole-dig-shovel-paws","t":"nature","q":"Why can a mole dig a new tunnel faster than a person could dig with a shovel?"},{"id":"monarch-butterfly-diapause-migration","t":"nature","q":"Why do the last monarch butterflies of summer live eight times longer than earlier generations?"},{"id":"monarch-caterpillar-toxin-shield","t":"nature","q":"Why doesn't the poison in milkweed leaves harm the caterpillars that eat nothing else?"},{"id":"monarch-overwintering-microclimate","t":"nature","q":"Why must the Mexican forest where monarchs spend winter stay within a narrow band of temperature?"},{"id":"monarch-population-decline-threats","t":"nature","q":"Why has the number of monarch butterflies migrating to Mexico dropped so sharply?"},{"id":"mongoose-cobra","t":"nature","q":"Why can a mongoose fight and beat a venomous cobra?"},{"id":"monoculture-forest-disease-risk","t":"nature","q":"Why can one disease wipe out an entire forest planted with just a single type of tree?"},{"id":"moonflower-night-bloom","t":"nature","q":"Why does the moonflower only open after dark?"},{"id":"mosquito-females-bite","t":"nature","q":"Why do only female mosquitoes bite?"},{"id":"mosquito-heat-co2","t":"nature","q":"Why can a mosquito find you in a pitch-black room?"},{"id":"mosquito-itch","t":"nature","q":"Why do mosquito bites itch?"},{"id":"mosquito-water-babies","t":"nature","q":"Why do baby mosquitoes live underwater when the adults can fly?"},{"id":"most-snakes-not-venomous","t":"nature","q":"Why aren't most snakes actually dangerous to people?"},{"id":"moth-circle-light","t":"nature","q":"Why do moths circle around a lamp instead of flying away?"},{"id":"moth-feathery-antennae","t":"nature","q":"Why do moths have feathery antennae shaped like combs?"},{"id":"moth-no-adult-mouth","t":"nature","q":"Why do some moths never eat as adults?"},{"id":"moth-ultrasound-ears","t":"nature","q":"Why do many moths have simple ears built straight into their chest?"},{"id":"mountain-pygmy-possum-snow-hibernation","t":"nature","q":"Why is a tiny possum the only Australian marsupial that hibernates under snow?"},{"id":"mountaingoat-climb-hooves","t":"nature","q":"Why can mountain goats stand and climb on cliffs so steep that almost nothing else can follow?"},{"id":"mudpuppy-external-gills","t":"nature","q":"Why does a mudpuppy salamander keep its feathery external gills for its whole life?"},{"id":"mudskipper-walk-on-land","t":"nature","q":"Why can some fish walk around on mud, out of the water entirely?"},{"id":"mushrooms","t":"nature","q":"Why aren't mushrooms plants?"},{"id":"musk-turtle-stink","t":"nature","q":"Why is one small turtle nicknamed the 'stinkpot'?"},{"id":"naked-mole-rat-colony-accent","t":"nature","q":"Why can naked mole rats tell which colony another mole rat is from just by its chirp?"},{"id":"naked-mole-rat-touch","t":"nature","q":"Why are naked mole rats almost blind, and how do they get around without seeing?"},{"id":"nectar-robbing-bees","t":"nature","q":"Why do some bees chew a hole in the side of a flower instead of going in the front?"},{"id":"needle-shape-water-loss","t":"nature","q":"Why are pine needles thin and waxy instead of flat and broad like most leaves?"},{"id":"nest-materials","t":"nature","q":"Why do some birds weave spider silk into their nests?"},{"id":"newt-pond-bottom-winter-dormancy","t":"nature","q":"Why does a newt sink to the bottom of a pond instead of leaving before winter?"},{"id":"newt-regrow-tail","t":"nature","q":"Why can a newt regrow its tail, its legs, and even part of its own eye?"},{"id":"night-flower-pale-color","t":"nature","q":"Why are so many night-blooming flowers white or pale instead of colourful?"},{"id":"nightingale-sing-at-night","t":"nature","q":"Why does a nightingale keep singing long after other birds have gone quiet?"},{"id":"no-nest-birds","t":"nature","q":"Why do some birds lay their eggs on bare ground instead of building a nest at all?"},{"id":"nocturnal","t":"nature","q":"Why do some animals only come out at night?"},{"id":"numbat-no-pouch","t":"nature","q":"Why doesn't a numbat have a pouch like other marsupials?"},{"id":"numbat-termite-appetite","t":"nature","q":"Why does a numbat need to eat up to 20,000 termites a day?"},{"id":"nurse-log-seedling-line","t":"nature","q":"Why do new trees often sprout in a perfectly straight line along a fallen, rotting log?"},{"id":"octopus-jet-propulsion","t":"nature","q":"Why can an octopus suddenly shoot backwards through the water in a burst of speed?"},{"id":"octopus-mother-guard","t":"nature","q":"Why does a mother octopus stop eating for months while guarding her eggs?"},{"id":"octopus-no-vocal-talk","t":"nature","q":"Why don't octopuses make sounds to talk to each other?"},{"id":"octopus-skin-light","t":"nature","q":"Why can an octopus \"see\" light even with skin on the very tip of its arm?"},{"id":"octopus-sleep-colour-change","t":"nature","q":"Why does a sleeping octopus sometimes flash through colours and patterns with its eyes closed?"},{"id":"octopus-sucker-taste","t":"nature","q":"Why can an octopus taste something the instant it touches it with a sucker?"},{"id":"old-trees-keep-growing-faster","t":"nature","q":"Why do some giant old trees actually keep adding wood faster each year rather than slowing down?"},{"id":"oldest-tree-secret-location","t":"nature","q":"Why do scientists keep the exact location of the world's oldest known tree secret?"},{"id":"opossum-play-dead","t":"nature","q":"Why do opossums play dead when they're scared?"},{"id":"orangutan-branch-bridging","t":"nature","q":"Why do orangutans move through trees so much more carefully than gibbons?"},{"id":"orangutan-long-childhood","t":"nature","q":"Why does a baby orangutan stay dependent on its mother for almost a decade?"},{"id":"orb-weaver-eats-web","t":"nature","q":"Why do many spiders eat their own web every single day?"},{"id":"orca-calf-podlife","t":"nature","q":"Why does an orca calf stay with its mother's pod for its entire life?"},{"id":"orchid-dust-seed","t":"nature","q":"Why does one orchid pod release more seeds than there are people in a big city, yet almost none of them grow?"},{"id":"orchid-mantis-flower-disguise","t":"nature","q":"Why does the orchid mantis dress up as a flower instead of hiding from insects?"},{"id":"orchid-wasp-mimicry","t":"nature","q":"Why does one orchid look and smell exactly like a female wasp?"},{"id":"ostrich-communal-nest","t":"nature","q":"Why do several female ostriches sometimes lay their eggs in one shared nest?"},{"id":"ostrich-head-sand-myth","t":"nature","q":"Why do people say ostriches bury their heads in the sand?"},{"id":"ostrich-no-fly","t":"nature","q":"Why can't an ostrich fly, even though it clearly has wings?"},{"id":"owl-butterfly-eyespots","t":"nature","q":"Why do some butterflies have giant fake eyes painted on their wings?"},{"id":"owl-ears-asymmetric","t":"nature","q":"Why are an owl's two ears sometimes set at different heights on its head?"},{"id":"owl-head","t":"nature","q":"Why can owls turn their heads so far?"},{"id":"owl-hoot","t":"nature","q":"Why do owls hoot in a low, booming voice instead of a high, chirpy song?"},{"id":"owl-pellets","t":"nature","q":"Why do owls cough up small pellets of fur and bone?"},{"id":"owl-silent-flight","t":"nature","q":"Why can owls fly through the night almost completely silently?"},{"id":"pacing-gait-camel-giraffe","t":"nature","q":"Why do camels and giraffes seem to rock from side to side when they walk?"},{"id":"paintedlady-migration-generations","t":"nature","q":"Why does one small butterfly's family cross an entire hemisphere in a single year?"},{"id":"paintedturtle-underwater-breathing-brumation","t":"nature","q":"Why can a turtle stay alive underwater all winter without ever coming up for air?"},{"id":"palm-tree-no-rings","t":"nature","q":"Why doesn't a palm tree trunk get a new ring every year the way an oak's does?"},{"id":"panda-cub-tiny","t":"nature","q":"Why is a newborn panda cub almost a thousand times smaller than its mother?"},{"id":"panda-twin-choice","t":"nature","q":"Why does a giant panda mother usually raise only one twin when she has two?"},{"id":"pando-one-tree-or-many","t":"nature","q":"Why do scientists argue about whether a huge grove of aspen trees is one tree or thousands?"},{"id":"paper-wasp-nests","t":"nature","q":"Why do paper wasp nests look like grey paper?"},{"id":"parasitic-wasp-eggs","t":"nature","q":"Why do some wasps lay their eggs inside other insects?"},{"id":"parrot-word-mimicry-myth","t":"nature","q":"Why is a parrot copying your words not the same as understanding them?"},{"id":"parrotfish-mucus-sleep-cocoon","t":"nature","q":"Why does a parrotfish blow a bubble of slime around itself before it sleeps?"},{"id":"passionflower-complex-shape","t":"nature","q":"Why is the passionflower shaped with so many strange rings and threads?"},{"id":"peacock-tail-anti-predator","t":"nature","q":"Why do peacocks suddenly fan their tail out at ground predators, not just other peacocks?"},{"id":"peacock-tail-infrasound","t":"nature","q":"Why does a peacock's shivering tail make sounds a person can't hear?"},{"id":"peanut-underground-pod","t":"nature","q":"Why does a peanut plant bury its own seed pods underground after flowering above it?"},{"id":"pelican-pouch","t":"nature","q":"Why can a pelican's beak scoop up more water than its own belly could ever hold?"},{"id":"penguin-chick-creche","t":"nature","q":"Why do penguin chicks huddle together in huge groups while their parents are away fishing?"},{"id":"penguin-egg-feet","t":"nature","q":"Why does a father emperor penguin balance an egg on his feet for two months straight?"},{"id":"penguin-swim-fly-underwater","t":"nature","q":"Why do penguins seem to fly underwater instead of just paddling?"},{"id":"pig-clever","t":"nature","q":"Why are pigs so clever?"},{"id":"pig-curly-tail","t":"nature","q":"Why do pigs have curly tails?"},{"id":"pig-look-up","t":"nature","q":"Why do people say pigs can't look up at the sky?"},{"id":"pig-mud-wallow","t":"nature","q":"Why do pigs roll in mud?"},{"id":"pig-pink-skin","t":"nature","q":"Why are so many pigs pink?"},{"id":"pig-snout-dig","t":"nature","q":"Why do pigs dig with their noses?"},{"id":"pigeon-magnetic-sense","t":"nature","q":"Why can homing pigeons find their way back over hundreds of kilometres of unfamiliar ground?"},{"id":"pine-cone-weather-hinge","t":"nature","q":"Why do some pine cones only open on dry days, not wet ones?"},{"id":"pit-viper-heat-sense","t":"nature","q":"Why can some snakes \"see\" a warm animal in total darkness?"},{"id":"plants-eat-bugs","t":"nature","q":"Why do some plants eat insects?"},{"id":"plants-soil","t":"nature","q":"Why do plants need soil?"},{"id":"platypus-echidna-hibernation-contrast","t":"nature","q":"Why does the platypus stay active in freezing water all winter while its cousin the echidna hibernates?"},{"id":"platypus-electroreception","t":"nature","q":"Why does a platypus close its eyes, ears and nose underwater and still find food?"},{"id":"platypus-lay-eggs","t":"nature","q":"Why does a platypus lay eggs even though it's a mammal?"},{"id":"platypus-no-stomach","t":"nature","q":"Why doesn't a platypus have a real stomach?"},{"id":"platypus-venom-spur","t":"nature","q":"Why are male platypuses venomous?"},{"id":"poison-dart-frog-captivity","t":"nature","q":"Why do poison dart frogs raised in a zoo lose their deadly poison?"},{"id":"poison-dart-frog-colours","t":"nature","q":"Why are poison dart frogs so brightly coloured instead of hiding in camouflage?"},{"id":"poison-frog-self-immunity","t":"nature","q":"Why doesn't a poison dart frog poison itself with its own toxin?"},{"id":"polarbear-black-skin","t":"nature","q":"Why isn't a polar bear actually white underneath its fur?"},{"id":"polarbear-patient-hunt","t":"nature","q":"Why does a polar bear sit so still for so long beside a hole in the ice?"},{"id":"pollen-allergy-sneeze","t":"nature","q":"Why does breathing in pollen make some people sneeze so much?"},{"id":"pollen-forecast-weather","t":"nature","q":"Why do pollen counts jump up so much on hot, dry, windy days?"},{"id":"pollen-grain-shapes","t":"nature","q":"Why does every kind of flower make a differently shaped pollen grain?"},{"id":"poppy-pepper-pot","t":"nature","q":"Why does a poppy seed pod work like a salt shaker in the wind?"},{"id":"porcupine-quills","t":"nature","q":"Why do porcupines have quills?"},{"id":"possum-not-opossum","t":"nature","q":"Why are Australian possums not the same animal as American opossums?"},{"id":"prairie-dog-alarm-calls","t":"nature","q":"Why do prairie dogs seem to describe a predator, not just warn about it?"},{"id":"predator-eyes-forward","t":"nature","q":"Why do predators like cats and wolves have eyes facing forward while their prey's eyes sit on the sides?"},{"id":"predator-surplus-kill","t":"nature","q":"Why do some predators sometimes kill far more than they could ever eat?"},{"id":"preen-oil","t":"nature","q":"Why do birds keep rubbing their beak against a spot near the base of their tail?"},{"id":"primate-infant-cling","t":"nature","q":"Why can a newborn gorilla or chimpanzee grip its mother's fur firmly enough to ride along from birth?"},{"id":"pufferfish-water-inflate","t":"nature","q":"Why does a pufferfish gulp water to blow itself up, instead of air?"},{"id":"puncture-vine-goathead","t":"nature","q":"Why does one weed seed have spikes hard enough to go through a shoe sole?"},{"id":"puppy-runt-myth","t":"nature","q":"Why isn't the runt of a litter doomed to be the weakest dog forever?"},{"id":"pygmy-seahorse-coral-camouflage","t":"nature","q":"Why was a tiny seahorse living on coral only discovered by accident?"},{"id":"python-labial-pits","t":"nature","q":"Why do pythons and boas have a whole row of pits along their lips?"},{"id":"python-shiver-incubate-eggs","t":"nature","q":"Why do some snake mothers shiver while guarding their eggs?"},{"id":"python-squeeze-heartbeat","t":"nature","q":"Why does a constricting snake keep squeezing exactly as long as it does?"},{"id":"quokka-smile-myth","t":"nature","q":"Why do quokkas look like they're smiling in photos?"},{"id":"rabbit-hare-baby-difference","t":"nature","q":"Why are baby hares born furred with their eyes open, while baby rabbits are born bald and blind?"},{"id":"rabbit-kit-visits","t":"nature","q":"Why does a mother rabbit only visit her babies twice a day?"},{"id":"rabbit-tail-flash-warning","t":"nature","q":"Why does a fleeing rabbit flash the white underside of its tail?"},{"id":"rabbits-binky","t":"nature","q":"Why do rabbits leap and twist in the air?"},{"id":"rabbits-blindspot","t":"nature","q":"Why can't rabbits see what's right under their own nose?"},{"id":"rabbits-ears","t":"nature","q":"Why do rabbits have such enormous ears?"},{"id":"rabbits-novomit","t":"nature","q":"Why can't rabbits be sick?"},{"id":"rabbits-poop","t":"nature","q":"Why do rabbits eat some of their own droppings?"},{"id":"rabbits-teeth","t":"nature","q":"Why do rabbits have to chew almost constantly?"},{"id":"rabbits-thump","t":"nature","q":"Why do rabbits thump their back feet?"},{"id":"raccoon-winter-torpor-den","t":"nature","q":"Why does a raccoon sometimes vanish for weeks during a cold snap without truly hibernating?"},{"id":"rainforest-canopy-layers","t":"nature","q":"Why do rainforest trees grow to such different heights in layers?"},{"id":"ram-headbutt","t":"nature","q":"Why do rams headbutt each other?"},{"id":"raptor-eyesight","t":"nature","q":"Why can a hawk spot a mouse from far higher up than a person ever could?"},{"id":"rattlesnake-rattle-warning","t":"nature","q":"Why do rattlesnakes shake a rattle instead of just hissing?"},{"id":"redback-toilet-myth","t":"nature","q":"Why did outback toilets get a reputation for hiding redback spiders?"},{"id":"reindeer-uv-snow","t":"nature","q":"Why can reindeer see ultraviolet light that stays completely invisible to us?"},{"id":"reptile-brumation","t":"nature","q":"Why do reptiles in cold places disappear for the whole winter?"},{"id":"reptile-egg-leathery-shell","t":"nature","q":"Why are most reptile eggs soft and leathery instead of hard like a bird's?"},{"id":"reptile-nictitating-membrane","t":"nature","q":"Why can some reptiles see clearly underwater without ever closing their eyes?"},{"id":"reptile-not-cold-blooded","t":"nature","q":"Why aren't reptiles really \"cold-blooded\"?"},{"id":"rhododendron-toxic-nectar","t":"nature","q":"Why can honey made from rhododendron flowers actually make people ill?"},{"id":"rightwhale-calving-quiet-water","t":"nature","q":"Why do right whales travel so far to have their calves in water far from food?"},{"id":"ring-tailed-lemur-stink-fight","t":"nature","q":"Why do ring-tailed lemurs wave their tails at each other during a 'stink fight'?"},{"id":"roadrunner-run-not-fly","t":"nature","q":"Why does a roadrunner sprint everywhere instead of flying?"},{"id":"rooster-crow-anytime","t":"nature","q":"Why do roosters crow at all hours, not just dawn?"},{"id":"rooster-spurs","t":"nature","q":"Why do roosters have spikes on their legs?"},{"id":"root-grafting-neighbours","t":"nature","q":"Why can roots from neighbouring trees sometimes fuse together underground?"},{"id":"roots-crack-footpaths","t":"nature","q":"Why can a tree's roots crack a concrete footpath even though they aren't very deep?"},{"id":"roots-spread-sideways","t":"nature","q":"Why do most tree roots spread out sideways near the surface instead of growing straight down?"},{"id":"saffron-crocus-flower","t":"nature","q":"Why does saffron cost so much more than almost any other spice?"},{"id":"salamander-no-tadpole-stage","t":"nature","q":"Why do some salamanders never go through a water-dwelling tadpole stage at all?"},{"id":"salmon-leap-waterfalls","t":"nature","q":"Why do migrating salmon leap straight up waterfalls instead of going around?"},{"id":"salmon-run-predator-feast","t":"nature","q":"Why do bears, eagles and wolves all gather at the same bend of a river once a year?"},{"id":"salmon-smell-home-river","t":"nature","q":"Why can a salmon find its way back to the exact stream where it hatched, years later?"},{"id":"salmon-stop-eating-freshwater","t":"nature","q":"Why do salmon stop eating altogether once they swim back into fresh water?"},{"id":"sandbox-tree-explode","t":"nature","q":"Why does the \"dynamite tree\" fire its seeds out with a loud bang?"},{"id":"sandhillcrane-staging-river","t":"nature","q":"Why do half a million cranes stop at the very same river every single spring?"},{"id":"sapwood-heartwood-colour","t":"nature","q":"Why does the middle of a tree trunk often turn a different, darker colour as the tree ages?"},{"id":"scallop-mirror-eyes","t":"nature","q":"Why does a scallop have dozens of tiny eyes lined up along the edge of its shell?"},{"id":"scorpion-babies-back","t":"nature","q":"Why do baby scorpions ride on their mother's back after they're born?"},{"id":"scorpion-danger-exaggerated","t":"nature","q":"Why are almost all scorpions harmless to people despite their fearsome reputation?"},{"id":"scorpion-glow-uv","t":"nature","q":"Why do scorpions glow blue-green under UV torchlight at night?"},{"id":"scorpion-live-birth","t":"nature","q":"Why do scorpions give birth to live babies instead of laying eggs?"},{"id":"scorpion-pincers-vs-sting","t":"nature","q":"Why does a scorpion have both crushing pincers and a stinging tail, and which does it use first?"},{"id":"scorpion-survive-desert","t":"nature","q":"Why can scorpions survive so long in the desert without food or water?"},{"id":"sea-bean-atlantic-drift","t":"nature","q":"Why do people sometimes find strange polished seeds washed up far from any matching tree?"},{"id":"sea-cucumber-eviscerate","t":"nature","q":"Why does a threatened sea cucumber sometimes shoot its own insides at a predator?"},{"id":"sea-otter-kelp-wrap-sleep","t":"nature","q":"Why do sea otters wrap themselves in kelp before they fall asleep?"},{"id":"sea-turtle-salty-tears","t":"nature","q":"Why do sea turtles look like they're crying on the beach?"},{"id":"seahorse-dad-pregnant","t":"nature","q":"Why is the father seahorse the one who gets pregnant?"},{"id":"seal-sealion-land-move","t":"nature","q":"Why do some seals waddle clumsily on land while sea lions can almost walk upright?"},{"id":"seal-whisker-wake","t":"nature","q":"Why can a blindfolded seal still track a fish it can neither see nor hear?"},{"id":"seed-bank-soil-dormant","t":"nature","q":"Why can bare dirt suddenly sprout new plants that nobody planted?"},{"id":"seed-cold-winter-wait","t":"nature","q":"Why won't some seeds sprout unless they've felt a proper cold winter first?"},{"id":"seed-dispersal-parent-shadow","t":"nature","q":"Why don't plants just drop their seeds straight down under themselves?"},{"id":"seeds-fly","t":"nature","q":"Why do dandelion seeds float away?"},{"id":"serotinous-cones-fire","t":"nature","q":"Why do some pine cones only open after they've been through a fire?"},{"id":"serval-leap","t":"nature","q":"Why can a serval leap so high to catch a bird out of the air?"},{"id":"shark-electroreception","t":"nature","q":"Why can a shark find a fish buried completely under the sand?"},{"id":"shark-ram-ventilation-sleep","t":"nature","q":"Why must some sharks keep swimming even while they rest?"},{"id":"shark-smell-blood-2","t":"nature","q":"Why is a shark's sense of smell so much sharper than ours?"},{"id":"shark-swim-or-sink-myth","t":"nature","q":"Why do people say every shark has to keep swimming forever or it will die?"},{"id":"sheep-flock-tight","t":"nature","q":"Why do sheep bunch together so tightly?"},{"id":"sheep-must-be-shorn","t":"nature","q":"Why do sheep need to be shorn?"},{"id":"sheepdog-eye","t":"nature","q":"Why do sheepdogs crouch and stare at sheep instead of barking?"},{"id":"sidewinder-snake-move","t":"nature","q":"Why do some desert snakes move sideways instead of straight ahead?"},{"id":"six-legs","t":"nature","q":"Why do all insects have exactly six legs?"},{"id":"skink-smooth-scales-burrow","t":"nature","q":"Why do skinks feel so smooth and shiny compared with other lizards?"},{"id":"skunk-communal-winter-den","t":"nature","q":"Why do normally solitary skunks share a den together for winter?"},{"id":"skunk-spray","t":"nature","q":"Why do skunks smell so bad?"},{"id":"sloth-baby-cling","t":"nature","q":"Why does a baby sloth cling to its mother's belly for months without falling off?"},{"id":"sloth-sleep-wild-vs-captive-myth","t":"nature","q":"Why do wild sloths actually sleep far less than the famous 20-hours-a-day figure suggests?"},{"id":"sloth-slow-move-muscle","t":"nature","q":"Why do sloths move so slowly nearly all the time, not just when they feel like it?"},{"id":"slow-loris-venom-elbow","t":"nature","q":"Why is the slow loris the only primate with a venomous bite?"},{"id":"slug-no-shell","t":"nature","q":"Why does a slug not have a shell like a snail does?"},{"id":"slug-squeeze-gap","t":"nature","q":"Why can a slug squeeze through a gap far thinner than its own body?"},{"id":"slug-two-slimes","t":"nature","q":"Why does a slug make two different kinds of slime at once?"},{"id":"smoke-germination","t":"nature","q":"Why do some seeds only sprout after smelling smoke?"},{"id":"snail-hibernate-seal","t":"nature","q":"Why do snails seal themselves inside their shell during winter?"},{"id":"snail-radula-teeth","t":"nature","q":"Why does a snail have thousands of teeth on its tongue?"},{"id":"snail-shell-grows-with-it","t":"nature","q":"Why can't a snail ever leave its shell?"},{"id":"snail-shell-spiral-same-shape","t":"nature","q":"Why does a snail's shell always spiral in exactly the same pattern as it grows?"},{"id":"snake-ground-vibration-hearing","t":"nature","q":"Why can a snake \"hear\" footsteps even though it has no ears at all?"},{"id":"snake-jaw-stretch-not-unhinge","t":"nature","q":"Why can a snake open its mouth around something bigger than its own head?"},{"id":"snake-no-legs-evolution","t":"nature","q":"Why don't snakes have any legs at all?"},{"id":"snake-one-lung","t":"nature","q":"Why do most snakes only really use one lung?"},{"id":"snake-rectilinear-concertina-move","t":"nature","q":"Why do heavy snakes like pythons sometimes glide forward in a straight line without any wiggling?"},{"id":"snake-skin","t":"nature","q":"Why do snakes shed their skin?"},{"id":"snake-skin-dry-not-slimy","t":"nature","q":"Why is snake skin dry instead of slimy?"},{"id":"snake-swallow-whole","t":"nature","q":"Why do snakes swallow their food whole instead of chewing it?"},{"id":"snake-tongue","t":"nature","q":"Why do snakes flick their tongues?"},{"id":"snake-venom-vs-poison","t":"nature","q":"Why are snakes called venomous rather than poisonous?"},{"id":"snowleopard-no-roar","t":"nature","q":"Why can't a snow leopard roar even though it's closely related to lions and tigers?"},{"id":"snowleopard-tail","t":"nature","q":"Why does a snow leopard have such a long, thick tail?"},{"id":"snowshoe-hare-daylight-trigger","t":"nature","q":"Why does a snowshoe hare know to turn white before the first snow has even fallen?"},{"id":"songbird-learn-song-from-father","t":"nature","q":"Why does a young songbird need to hear its father sing to learn its own song properly?"},{"id":"spadefoot-toad-underground-aestivation","t":"nature","q":"Why can a spadefoot toad wait underground for years between rains?"},{"id":"sperm-whale-click-codas","t":"nature","q":"Why do different sperm whale families 'speak' in different click patterns?"},{"id":"spermwhale-vertical-logging-sleep","t":"nature","q":"Why do sperm whales sometimes float upright near the surface like drifting logs?"},{"id":"spider-ballooning","t":"nature","q":"Why do baby spiders float away through the air on silk?"},{"id":"spider-bathtub-stuck","t":"nature","q":"Why do spiders get trapped in the bath but climb walls with ease?"},{"id":"spider-blue-blood","t":"nature","q":"Why is a spider's blood blue instead of red?"},{"id":"spider-silk-strength","t":"nature","q":"Why is spider silk, gram for gram, stronger than steel?"},{"id":"spider-sleep-bite-myth","t":"nature","q":"Why don't spiders usually bite people while they're asleep?"},{"id":"spider-web","t":"nature","q":"Why don't spiders stick to their own webs?"},{"id":"spider-web-pluck-courtship","t":"nature","q":"Why does a male spider pluck a female's web like a guitar string before approaching?"},{"id":"spiders-without-webs","t":"nature","q":"Why do some spiders never build a web at all?"},{"id":"squid-ink-decoy-cloud","t":"nature","q":"Why does squid ink sometimes form a blob shaped roughly like the squid itself?"},{"id":"squirrel-climb-headfirst","t":"nature","q":"Why can squirrels run straight down a tree trunk headfirst without falling?"},{"id":"squirrel-forgotten-acorns","t":"nature","q":"Why do squirrels bury far more acorns than they ever eat?"},{"id":"squirting-cucumber-blast","t":"nature","q":"Why does a squirting cucumber suddenly fire its seeds out in a jet?"},{"id":"star-nosed-mole-touch","t":"nature","q":"Why does a star-nosed mole have 22 pink tentacles ringing its nose?"},{"id":"starfish-arm-eyes","t":"nature","q":"Why does a starfish have an eye on the tip of every single arm?"},{"id":"starfish-tube-feet-move","t":"nature","q":"Why does a starfish have hundreds of tiny feet under its arms instead of just a few big ones?"},{"id":"starling-murmuration","t":"nature","q":"Why do huge flocks of starlings swirl into shifting shapes at dusk?"},{"id":"stick-insect-camouflage","t":"nature","q":"Why do stick insects look exactly like twigs?"},{"id":"stick-insect-eggs-ants","t":"nature","q":"Why do some stick insect eggs trick ants into planting them like seeds?"},{"id":"stick-insect-twig-camouflage","t":"nature","q":"Why do stick insects sway gently while walking instead of moving smoothly?"},{"id":"stigma-sticky-catch-pollen","t":"nature","q":"Why does a flower's stigma feel sticky or look feathery instead of smooth?"},{"id":"stonefish-camouflage-venom","t":"nature","q":"Why is a fish that looks exactly like a lump of rock also one of the most dangerous fish alive?"},{"id":"strangler-fig-starts-high","t":"nature","q":"Why does a strangler fig start life growing high up on another tree instead of down in the soil?"},{"id":"sugar-glider-membrane","t":"nature","q":"Why can a sugar glider glide between trees?"},{"id":"sunflowers-turn","t":"nature","q":"Why do sunflowers follow the Sun?"},{"id":"suriname-toad-eggs-on-back","t":"nature","q":"Why do baby Suriname toads hatch out of holes in their own mother's back?"},{"id":"svalbard-seed-vault","t":"nature","q":"Why do scientists store millions of seeds deep inside a frozen Arctic mountain?"},{"id":"swan-cygnet-ride","t":"nature","q":"Why do baby swans sometimes ride on a parent's back instead of swimming themselves?"},{"id":"swan-water-takeoff-run","t":"nature","q":"Why does a swan need a long running start across water before it can fly?"},{"id":"tadpole-gills-to-lungs","t":"nature","q":"Why does a tadpole start life breathing water but end it breathing air?"},{"id":"tadpole-tail-disappear","t":"nature","q":"Why does a tadpole's tail disappear instead of falling off?"},{"id":"tallest-tree-height-limit","t":"nature","q":"Why can't trees grow much taller than about 130 metres?"},{"id":"tarantula-hair-flick","t":"nature","q":"Why do tarantulas kick tiny hairs off their own legs at enemies?"},{"id":"tasdevil-bite","t":"nature","q":"Why does a Tasmanian devil have such a surprisingly powerful bite for such a small animal?"},{"id":"termite-blind-workers","t":"nature","q":"Why do most termites never see daylight, or anything at all?"},{"id":"termite-mound-aircon","t":"nature","q":"Why are termite mounds built with tall chimneys?"},{"id":"termite-wood-digestion","t":"nature","q":"Why can termites digest wood when hardly any other animal can?"},{"id":"texas-horned-lizard-blood-eyes","t":"nature","q":"Why can a horned lizard shoot blood out of its own eyes?"},{"id":"thick-bark-fire-survival","t":"nature","q":"Why does thick bark help some trees survive a bushfire that kills others nearby?"},{"id":"thin-living-layer","t":"nature","q":"Why is only a thin layer just under the bark actually alive in a tree trunk?"},{"id":"thorn-bug-mimicry","t":"nature","q":"Why do some tiny insects grow a huge, curved spike out of their own back?"},{"id":"thorny-devil-fake-head","t":"nature","q":"Why does a thorny devil have a fake head on the back of its neck?"},{"id":"thorny-devil-skin-drink","t":"nature","q":"Why can a thorny devil \"drink\" water through its skin?"},{"id":"tiger-cub-learn-hunt","t":"nature","q":"Why do tiger cubs stay with their mother for almost two years before hunting alone?"},{"id":"tiger-solitary","t":"nature","q":"Why do tigers live and hunt completely alone?"},{"id":"tiger-stripes-unique","t":"nature","q":"Why is no two tigers' stripes exactly the same?"},{"id":"tiger-swim","t":"nature","q":"Why do tigers swim so easily when most cats hate water?"},{"id":"tiger-white-rare","t":"nature","q":"Why are white tigers so rare in the wild?"},{"id":"toad-no-teeth","t":"nature","q":"Why do toads swallow their prey whole instead of chewing it?"},{"id":"toad-puff-up-defense","t":"nature","q":"Why do some toads puff themselves up when they feel threatened?"},{"id":"toad-scream-defense","t":"nature","q":"Why do some toads let out a sudden, high-pitched scream when a predator grabs them?"},{"id":"toad-vs-frog-eggs-pattern","t":"nature","q":"Why do toad eggs come in long strings while frog eggs come in round clumps?"},{"id":"toad-warts-myth","t":"nature","q":"Why do people say touching a toad gives you warts?"},{"id":"toadfish-singing-swim-bladder","t":"nature","q":"Why can a fish sing by squeezing its own swim bladder?"},{"id":"tortoise-slow-heavy-shell","t":"nature","q":"Why do tortoises move so slowly compared to almost every other reptile?"},{"id":"touch-me-not-impatiens","t":"nature","q":"Why does a touch-me-not seed pod explode the instant you touch it?"},{"id":"trapdoor-spider-door","t":"nature","q":"Why do trapdoor spiders build a hinged lid over their burrow?"},{"id":"tree-frog-toe-pads","t":"nature","q":"Why can a tree frog cling to smooth glass upside down without falling?"},{"id":"tree-rings","t":"nature","q":"Why do trees have rings inside?"},{"id":"tree-wound-never-heals","t":"nature","q":"Why doesn't a wound in a tree's bark ever truly heal over like human skin?"},{"id":"treekangaroo-climb","t":"nature","q":"Why can tree kangaroos climb trees when ordinary kangaroos can barely manage a gentle slope?"},{"id":"trees-bend-not-snap","t":"nature","q":"Why do trees bend in strong wind instead of snapping straight away?"},{"id":"trees-dont-breathe","t":"nature","q":"Why don't trees \"breathe\" the same way animals do?"},{"id":"treesquirrel-active-all-winter","t":"nature","q":"Why do the squirrels in your backyard stay active all winter instead of hibernating?"},{"id":"tuatara-living-fossil","t":"nature","q":"Why is the tuatara called a living fossil?"},{"id":"tumbleweed-rolls","t":"nature","q":"Why does a whole dried plant sometimes go rolling across a field on its own?"},{"id":"tuna-transatlantic-migration","t":"nature","q":"Why do bluefin tuna cross an entire ocean and then return to the same place to breed?"},{"id":"turtle-ascension-island-navigation","t":"nature","q":"Why can a green turtle find a tiny island in the middle of an ocean with no landmarks?"},{"id":"turtle-cant-leave-shell","t":"nature","q":"Why can't a turtle crawl out of its shell?"},{"id":"turtle-flipper-swim-crawl","t":"nature","q":"Why does a sea turtle move so gracefully in water but so slowly and awkwardly on a beach?"},{"id":"turtle-no-teeth-beak","t":"nature","q":"Why don't turtles have any teeth?"},{"id":"turtle-return-same-beach","t":"nature","q":"Why do sea turtles swim back to lay eggs on the very beach where they hatched?"},{"id":"turtle-shell-scutes-rings","t":"nature","q":"Why does a turtle's shell look like it's made of separate patterned plates?"},{"id":"turtle-temperature-sex","t":"nature","q":"Why does the temperature of a turtle's nest decide whether it hatches male or female?"},{"id":"vampire-bat-nose-heat","t":"nature","q":"Why can a vampire bat find the exact spot to bite in total darkness?"},{"id":"vanilla-hand-pollination","t":"nature","q":"Why do people pollinate vanilla flowers by hand with a toothpick?"},{"id":"vervet-monkey-alarm-calls","t":"nature","q":"Why do vervet monkeys use a different call for a snake than for an eagle?"},{"id":"viceroy-monarch-mimicry","t":"nature","q":"Why do viceroy and monarch butterflies look alike if only one is supposed to be poisonous?"},{"id":"viper-fangs-fold-away","t":"nature","q":"Why do some snakes fold their fangs flat against the roof of their mouth?"},{"id":"vulture-hiss-no-voice","t":"nature","q":"Why can vultures only hiss and grunt instead of calling out properly?"},{"id":"vulture-smell-carrion","t":"nature","q":"Why can a turkey vulture smell a dead animal hidden under a thick forest canopy?"},{"id":"vulture-thermal-soar","t":"nature","q":"Why do vultures circle slowly in the sky without ever flapping their wings?"},{"id":"walking-stick-egg-seed-mimicry","t":"nature","q":"Why do some stick insect eggs look and even smell like plant seeds?"},{"id":"walnut-tree-juglone","t":"nature","q":"Why does hardly anything grow well in the ground under a black walnut tree?"},{"id":"wasp-pollinator-myth","t":"nature","q":"Why are wasps actually useful pollinators, even though most people just try to avoid them?"},{"id":"wasp-queen-solo-overwinter","t":"nature","q":"Why does an entire wasp nest die off in autumn except for one type of wasp?"},{"id":"wasp-sting-repeat","t":"nature","q":"Why can a wasp sting you more than once, unlike a honeybee?"},{"id":"water-lily-floating-seed","t":"nature","q":"Why can a water lily seed float for days before it finally sinks?"},{"id":"water-strider-surface-vibration","t":"nature","q":"Why can a water strider feel a mosquito land on the far side of a pond?"},{"id":"water-to-treetop-no-pump","t":"nature","q":"Why can water reach the very top leaves of a tall tree without any kind of pump?"},{"id":"waterbug-dad-eggs","t":"nature","q":"Why does a father giant water bug carry dozens of eggs glued to his own back?"},{"id":"wattle-hard-coat-fire-crack","t":"nature","q":"Why do some wattle seeds need to be scorched before they can even take up water?"},{"id":"wattle-seed-elaiosome-ant","t":"nature","q":"Why do some seeds carry their own tiny packed lunch to attract ants?"},{"id":"weaver-nest","t":"nature","q":"Why do weaver birds knot their nests instead of just piling up sticks?"},{"id":"western-monarch-california-coast","t":"nature","q":"Why do monarch butterflies west of the Rocky Mountains never fly to Mexico at all?"},{"id":"wetacricket-freeze-tolerant","t":"nature","q":"Why can a giant New Zealand cricket freeze solid overnight and hop away by morning?"},{"id":"whale-calf-milk","t":"nature","q":"Why can a whale calf drink its mother's milk underwater without drowning?"},{"id":"whale-infrasound-talk","t":"nature","q":"Why can whales talk to each other across an entire ocean?"},{"id":"whaleshark-migration-plankton","t":"nature","q":"Why do whale sharks turn up at the same reef at almost the same time every year?"},{"id":"wilddog-hunt-success","t":"nature","q":"Why do African wild dogs succeed at hunting far more often than lions do?"},{"id":"wildebeest-calving-synchronized","t":"nature","q":"Why do almost all wildebeest calves get born within the same few weeks?"},{"id":"wildebeest-circular-migration-rain","t":"nature","q":"Why does the wildebeest migration travel in a giant circle instead of a straight line?"},{"id":"wildebeest-river-crossing-hazard","t":"nature","q":"Why do so many wildebeest drown crossing the same river every year?"},{"id":"wildfowl-flightless-moult","t":"nature","q":"Why do some water birds lose the ability to fly for weeks every year?"},{"id":"willie-wagtail-tail","t":"nature","q":"Why does a willie wagtail wag its tail almost constantly while it walks?"},{"id":"wind-pollinated-flower-plain","t":"nature","q":"Why do grasses have flowers that don't look like flowers at all?"},{"id":"winged-seeds-samara","t":"nature","q":"Why do some tree seeds have papery wings attached, like tiny helicopter blades?"},{"id":"winter-cell-antifreeze","t":"nature","q":"Why don't a tree's living cells freeze and burst during a hard winter?"},{"id":"witch-hazel-seed-flick","t":"nature","q":"Why can a witch hazel shrub flick its seeds several metres through the air?"},{"id":"wolf-alpha-myth","t":"nature","q":"Why was the idea of an \"alpha wolf\" fighting its way to the top actually wrong?"},{"id":"wolf-howl","t":"nature","q":"Why do wolves howl?"},{"id":"wolf-pack-big-prey","t":"nature","q":"Why can a wolf pack bring down prey far bigger than any single wolf?"},{"id":"wolf-pack-hunt","t":"nature","q":"Why do wolves hunt in packs instead of alone?"},{"id":"wolf-pup-den-babysitters","t":"nature","q":"Why do wolf pups get raised by the whole pack instead of just their parents?"},{"id":"wolf-spider-babies-back","t":"nature","q":"Why do baby wolf spiders ride around on their mother's back?"},{"id":"wombat-backward-pouch","t":"nature","q":"Why does a wombat's pouch face backwards?"},{"id":"wombat-cube-poo","t":"nature","q":"Why do wombats poo in cubes?"},{"id":"wombat-rump-shield","t":"nature","q":"Why do wombats use their rear end to defend their burrow?"},{"id":"wombat-slow-metabolism","t":"nature","q":"Why do wombats have such a slow metabolism for their size?"},{"id":"wombat-teeth-grow","t":"nature","q":"Why do a wombat's front teeth never stop growing?"},{"id":"wood-frog-freezes-solid","t":"nature","q":"Why doesn't a wood frog die when it freezes solid over winter?"},{"id":"wood-wide-web-fungi","t":"nature","q":"Why do scientists say a forest is connected by an underground fungal network?"},{"id":"woodlice-curl-ball","t":"nature","q":"Why do some woodlice roll into a tight little ball when touched?"},{"id":"woodlice-not-insects","t":"nature","q":"Why are woodlice actually more closely related to crabs than to insects?"},{"id":"woodpecker-climb-feet-tail","t":"nature","q":"Why can a woodpecker cling to a tree trunk while hammering, without falling backward?"},{"id":"woodpecker-drum-metal-territory","t":"nature","q":"Why do some woodpeckers drum on metal roofs and signs instead of on trees?"},{"id":"woodpecker-headache","t":"nature","q":"Why doesn't a woodpecker knock itself silly hammering its beak into a tree all day?"},{"id":"wool-not-hair","t":"nature","q":"Why is wool so different from hair?"},{"id":"worm-both-male-female","t":"nature","q":"Why is every earthworm both male and female at the same time?"},{"id":"worm-breathe-skin","t":"nature","q":"Why do worms breathe through their skin instead of having lungs?"},{"id":"worm-cut-half-myth","t":"nature","q":"Why doesn't cutting an earthworm in half make two new worms?"},{"id":"worm-five-hearts","t":"nature","q":"Why do earthworms have five pairs of hearts instead of just one?"},{"id":"worm-improve-soil","t":"nature","q":"Why did Charles Darwin call earthworms one of the most important animals on Earth?"},{"id":"worm-no-eyes-sense-light","t":"nature","q":"Why can worms sense light and danger without having any eyes?"},{"id":"worms-rain","t":"nature","q":"Why do worms come out when it rains?"},{"id":"zebra-lead-wildebeest-migration","t":"nature","q":"Why do zebras usually lead the herd on the Serengeti migration?"},{"id":"zebra-stripes","t":"nature","q":"Why do zebras have stripes?"},{"id":"accretion-disk-glows-xray","t":"space","q":"Why does gas falling into a black hole glow so brightly before it disappears?"},{"id":"air-launch-rocket-plane","t":"space","q":"Why do some small rockets launch from underneath an aeroplane instead of a pad on the ground?"},{"id":"algol-eclipsing-paradox","t":"space","q":"Why does the star Algol dim every few days, and why is its smaller star the unexpected age?"},{"id":"andromeda-eye-vs-camera","t":"space","q":"Why does Andromeda look like a dim smudge through binoculars but a full spiral in photos?"},{"id":"andromeda-farthest-visible","t":"space","q":"Why is the Andromeda Galaxy the most distant thing most people will ever see with their own eyes?"},{"id":"andromeda-star-count-vs-milky-way","t":"space","q":"Why does Andromeda have far more stars than the Milky Way, yet may not outweigh it?"},{"id":"apollo-flag","t":"space","q":"Why does the flag in Apollo photos look like it's rippling when there's no wind on the Moon?"},{"id":"apollo-footprints","t":"space","q":"Why will astronaut bootprints on the Moon probably last millions of years?"},{"id":"apollo-no-stars","t":"space","q":"Why don't any stars show up in Apollo photos of the black lunar sky?"},{"id":"apophis-close-pass","t":"space","q":"Why will the asteroid Apophis fly closer to Earth than some satellites in 2029?"},{"id":"asteroid-belt-empty-myth","t":"space","q":"Why is the asteroid belt mostly empty space, not a crowded maze like in the movies?"},{"id":"asteroid-families","t":"space","q":"Why do groups of asteroids share almost the same orbit, like a scattered family?"},{"id":"asteroid-moons","t":"space","q":"Why do some asteroids have their own tiny moons?"},{"id":"asteroid-naming","t":"space","q":"Why do asteroids often end up named after ordinary people instead of gods or heroes?"},{"id":"asteroid-rubble-pile","t":"space","q":"Why are many asteroids loose piles of rubble instead of solid rock?"},{"id":"asteroid-shapes-lumpy","t":"space","q":"Why are most asteroids lumpy potatoes instead of round balls?"},{"id":"asteroid-tumbling","t":"space","q":"Why do some asteroids tumble end over end instead of spinning smoothly on an axis?"},{"id":"asteroid-types-colour","t":"space","q":"Why do asteroids come in different colours depending on what they're made of?"},{"id":"asteroids","t":"space","q":"Why are there asteroids?"},{"id":"astronaut-daily-exercise","t":"space","q":"Why do astronauts spend two hours a day on exercise machines in space?"},{"id":"astronauts-float","t":"space","q":"Why do astronauts float?"},{"id":"astronauts-grow-taller-temporary","t":"space","q":"Why do astronauts come home from space a few centimetres taller?"},{"id":"astronauts-not-no-gravity","t":"space","q":"Why do astronauts float if gravity is still pulling on them up there?"},{"id":"astronauts-pressed-launch-seat","t":"space","q":"Why do astronauts get pressed hard into their seats during launch but feel almost nothing once in orbit?"},{"id":"balance-relearning-after-return","t":"space","q":"Why do astronauts sometimes need help just to stand after landing?"},{"id":"barred-spiral-bar","t":"space","q":"Why do many spiral galaxies have a straight bar of stars through the middle?"},{"id":"baryon-acoustic-oscillations","t":"space","q":"Why did sound waves in the baby universe leave fingerprints we can still measure today?"},{"id":"beagle-2-lost","t":"space","q":"Why did it take over a decade to find out what happened to a lost Mars lander?"},{"id":"before-big-bang-unknown","t":"space","q":"Why can't scientists say what happened before the Big Bang?"},{"id":"big-bang","t":"space","q":"Why do we think there was a Big Bang?"},{"id":"big-bang-name-origin","t":"space","q":"Why is it called the Big Bang when nobody actually heard a bang?"},{"id":"big-bang-not-a-point","t":"space","q":"Why wasn't the Big Bang an explosion happening at one spot in space?"},{"id":"big-bang-nucleosynthesis-minutes","t":"space","q":"Why did almost all the universe's simplest atoms form within its first few minutes?"},{"id":"big-bang-singularity-breakdown","t":"space","q":"Why do scientists say their equations break right at the very start of everything?"},{"id":"big-bang-theory-scope-limit","t":"space","q":"Why doesn't the Big Bang theory actually explain where space and time came from?"},{"id":"binary-black-hole-inspiral","t":"space","q":"Why do two orbiting black holes speed up right before they finally collide?"},{"id":"binary-orbit-barycentre","t":"space","q":"Why do two stars in a pair not really orbit each other directly?"},{"id":"binary-star-common","t":"space","q":"Why do most of the brightest stars in the night sky actually have a hidden partner star?"},{"id":"black-hole-centre-unknown","t":"space","q":"Why don't scientists know what's really at the centre of a black hole?"},{"id":"black-hole-chirp-sound","t":"space","q":"Why do scientists talk about black hole collisions making a \"chirp\"?"},{"id":"black-hole-information-paradox","t":"space","q":"Why do scientists argue about whether a black hole can truly destroy information?"},{"id":"black-hole-jets","t":"space","q":"Why do some black holes shoot jets of matter out at nearly light speed instead of swallowing it?"},{"id":"black-hole-merger-gravitational-waves","t":"space","q":"Why did two colliding black holes make space itself ripple?"},{"id":"black-hole-not-actually-hole","t":"space","q":"Why isn't a black hole actually a hole in space?"},{"id":"black-hole-seen-by-glow-not-light","t":"space","q":"Why can astronomers \"see\" a black hole if no light can escape it?"},{"id":"black-hole-silhouette-shadow","t":"space","q":"Why does a black hole cast a \"shadow\" bigger than the black hole itself?"},{"id":"black-hole-size-gap-mystery","t":"space","q":"Why do black holes come in two common sizes with almost nothing in between?"},{"id":"black-hole-surface-gravity-vs-star","t":"space","q":"Why is the gravity right at a black hole's surface so much fiercer than the same mass spread out as a star?"},{"id":"black-hole-time-dilation","t":"space","q":"Why would a clock near a black hole tick slower than one far away?"},{"id":"black-holes","t":"space","q":"Why can't light escape a black hole?"},{"id":"black-holes-evaporate-hawking","t":"space","q":"Why do black holes slowly lose mass and could eventually vanish?"},{"id":"black-holes-grow-by-eating","t":"space","q":"Why do black holes get bigger every time they swallow something?"},{"id":"black-holes-spin","t":"space","q":"Why do black holes spin, some faster than a kitchen blender's blade?"},{"id":"blazar-pointed-jet","t":"space","q":"Why does a black hole's jet aimed straight at Earth look like the brightest thing in the sky?"},{"id":"blood-moon","t":"space","q":"Why does the Moon turn red during a lunar eclipse?"},{"id":"bok-globule","t":"space","q":"Why do small dark blobs inside glowing nebulae sometimes hide stars being born?"},{"id":"bone-loss-microgravity","t":"space","q":"Why do astronauts' bones get thinner the longer they stay in space?"},{"id":"boomerang-nebula-coldest","t":"space","q":"Why is a wisp of gas around a dying star the coldest known place in the universe?"},{"id":"booster-parachute-recovery","t":"space","q":"Why do some rocket boosters splash down under parachutes instead of landing upright?"},{"id":"breathe-planets","t":"space","q":"Why can't we breathe on other planets?"},{"id":"brown-dwarf-failed-star","t":"space","q":"Why are brown dwarfs sometimes called failed stars?"},{"id":"bullet-cluster-dark-matter","t":"space","q":"Why do astronomers point to one galaxy cluster crash as the best proof dark matter is real?"},{"id":"callisto-geologically-dead","t":"space","q":"Why is Callisto considered geologically dead compared to Jupiter's other big moons?"},{"id":"callisto-most-cratered","t":"space","q":"Why is Callisto's surface the most heavily cratered in the solar system?"},{"id":"cartwheel-ring-galaxy","t":"space","q":"Why do some rare galaxies look like a glowing ring instead of a spiral or a ball?"},{"id":"cassini-grand-finale","t":"space","q":"Why did NASA deliberately crash a working spacecraft into Saturn?"},{"id":"cassini-ring-dives","t":"space","q":"Why did Cassini dive through the gap between Saturn and its rings 22 times before it died?"},{"id":"cepheid-distance-ruler","t":"space","q":"Why did pulsing Cepheid stars let astronomers finally measure distances across the universe?"},{"id":"cepheid-pulsing-clock","t":"space","q":"Why do certain stars brighten and dim on an exact, repeating schedule?"},{"id":"ceres-dwarf-planet","t":"space","q":"Why is Ceres both an asteroid and a dwarf planet?"},{"id":"chandrasekhar-limit","t":"space","q":"Why is there an exact mass limit that a white dwarf can never cross?"},{"id":"chandrayaan-pragyan-south-pole","t":"space","q":"Why did India's Moon rover aim for a spot near the Moon's south pole that no one had ever landed near before?"},{"id":"change4-yutu-farside","t":"space","q":"Why did landing on the far side of the Moon need a whole extra satellite just to make it work?"},{"id":"charon-red-pole","t":"space","q":"Why does Charon's north pole have a strange reddish-brown stain, nicknamed Mordor?"},{"id":"chemcam-laser","t":"space","q":"Why does Curiosity fire a laser at rocks before it even touches them?"},{"id":"chicxulub-impact-winter","t":"space","q":"Why did one asteroid impact kill off the dinosaurs when the blast itself wasn't enough?"},{"id":"cluster-gravitational-lensing","t":"space","q":"Why can a giant galaxy cluster bend the light of galaxies far behind it into curved arcs?"},{"id":"cluster-xray-gas","t":"space","q":"Why does the space between galaxies in a cluster glow brightly in X-rays?"},{"id":"cmb-accidental-discovery","t":"space","q":"Why did two engineers cleaning pigeon droppings off an antenna stumble onto proof of the Big Bang?"},{"id":"cmb-nearly-uniform","t":"space","q":"Why is the universe's oldest light almost exactly the same everywhere you look?"},{"id":"cmb-ripples-seeds","t":"space","q":"Why do tiny wrinkles in the universe's oldest light matter so much?"},{"id":"cme-vs-flare","t":"space","q":"Why are coronal mass ejections different from ordinary solar flares?"},{"id":"co2-bubble-sleeping-danger","t":"space","q":"Why do fans have to run all night around a sleeping astronaut's head?"},{"id":"colony-3d-print","t":"space","q":"Why might future Moon buildings be 3D-printed from Moon dust instead of built from bricks?"},{"id":"colony-radiation","t":"space","q":"Why would people living on the Moon need walls of thick shielding?"},{"id":"colony-two-week-night","t":"space","q":"Why would a Moon colony have to survive a two-week-long night?"},{"id":"colony-water-ice","t":"space","q":"Why would a Moon base most likely be built near the poles rather than the equator?"},{"id":"comet-67p-shape","t":"space","q":"Why is the comet Rosetta orbited shaped like a rubber duck?"},{"id":"comet-coma","t":"space","q":"Why does a comet grow a fuzzy glowing head before it grows a tail?"},{"id":"comet-dark-surface","t":"space","q":"Why is a comet's surface one of the darkest things in the solar system?"},{"id":"comet-green-glow","t":"space","q":"Why do some comets glow green as they near the Sun?"},{"id":"comet-jets-uneven","t":"space","q":"Why does a comet sometimes spurt gas from only one patch of its surface?"},{"id":"comet-naming-discoverer","t":"space","q":"Why are comets usually named after the people who found them, not myths or numbers?"},{"id":"comet-nucleus-not-just-snowball","t":"space","q":"Why is calling a comet's core a 'dirty snowball' only half the story?"},{"id":"comet-orbit-shape","t":"space","q":"Why do comets swing in from far beyond Pluto and then loop all the way back out again?"},{"id":"comet-splitting","t":"space","q":"Why do some comets break apart into several pieces before anyone even sees them coming?"},{"id":"comet-tail","t":"space","q":"Why do comets have tails?"},{"id":"comet-tail-length","t":"space","q":"Why can a comet's tail stretch millions of kilometres from a nucleus only a few kilometres wide?"},{"id":"comet-two-tails","t":"space","q":"Why can a comet grow two completely different tails at the same time?"},{"id":"comet-vs-asteroid-difference","t":"space","q":"Why is telling a comet from an asteroid sometimes surprisingly hard?"},{"id":"comet-water-earth","t":"space","q":"Why do some scientists think comets helped bring water to Earth?"},{"id":"core-light-slow","t":"space","q":"Why can light take thousands of years just to escape the Sun's core?"},{"id":"core-vs-surface-8min","t":"space","q":"Why is sunlight both ancient and only eight minutes old at once?"},{"id":"cosmic-inflation","t":"space","q":"Why do scientists think the universe suddenly stretched enormously in its first instant?"},{"id":"cosmic-neutrino-background","t":"space","q":"Why is the universe still full of ghostly particles from one second after the Big Bang?"},{"id":"cosmic-web-voids","t":"space","q":"Why are galaxies arranged in a web instead of being spread out evenly?"},{"id":"cosmological-principle","t":"space","q":"Why do astronomers assume the universe looks roughly the same everywhere?"},{"id":"crater-central-peak","t":"space","q":"Why do some big Moon craters have a mountain sitting right in the middle?"},{"id":"crater-chains","t":"space","q":"Why do small Moon craters sometimes line up in a straight chain?"},{"id":"crater-counting-age","t":"space","q":"Why can scientists tell how old a patch of Moon ground is just by counting its craters?"},{"id":"crater-rays","t":"space","q":"Why do some Moon craters have bright rays streaking out of them?"},{"id":"crescent-shape","t":"space","q":"Why is a crescent Moon curved like a fingernail instead of a straight-edged slice?"},{"id":"crewed-rocket-escape-tower","t":"space","q":"Why do some crewed rockets have a small pointed tower sitting right on top of the capsule?"},{"id":"curiosity-nuclear-power","t":"space","q":"Why do Curiosity and Perseverance run on nuclear power instead of solar panels?"},{"id":"dark-ages-of-universe","t":"space","q":"Why is there a stretch of cosmic history astronomers call the dark ages?"},{"id":"dark-matter-halo-extent","t":"space","q":"Why does a galaxy's invisible dark matter stretch so much further than its visible stars?"},{"id":"dark-matter-universe-scaffolding","t":"space","q":"Why do scientists think invisible matter shaped where every galaxy formed?"},{"id":"dart-mission","t":"space","q":"Why did NASA crash a spacecraft into an asteroid on purpose?"},{"id":"dawn-two-worlds","t":"space","q":"Why could one spacecraft visit two completely different worlds that no other probe has ever orbited?"},{"id":"day-night","t":"space","q":"Why do we have day and night?"},{"id":"deep-impact-comet-punch","t":"space","q":"Why did NASA fire a copper block at a comet just to see what was hiding inside it?"},{"id":"deep-space-network","t":"space","q":"Why does NASA need giant dishes on three different continents just to talk to its probes?"},{"id":"deimos-slow-crawl","t":"space","q":"Why does Mars's other moon Deimos seem to barely move across the sky at all?"},{"id":"dione-wispy-ice-cliffs","t":"space","q":"Why did pale, wispy streaks on Saturn's moon Dione turn out to be something else entirely?"},{"id":"dwarf-galaxies-common","t":"space","q":"Why are most galaxies in the universe small and dim rather than giants like ours?"},{"id":"early-galaxies-messy","t":"space","q":"Why did the very first galaxies look so much smaller and messier than today's?"},{"id":"early-universe-huge-black-holes-puzzle","t":"space","q":"Why do some black holes seem too big to have grown so soon after the Big Bang?"},{"id":"early-universe-opaque","t":"space","q":"Why couldn't light travel freely through the very early universe?"},{"id":"earth-axis-wobble","t":"space","q":"Why does Earth's axis slowly trace a circle in the sky over thousands of years?"},{"id":"earth-continents-float","t":"space","q":"Why do continents sit higher than the ocean floor instead of being level?"},{"id":"earth-day-lengthen","t":"space","q":"Why are Earth's days slowly getting longer because of the Moon?"},{"id":"earth-day-lengthening","t":"space","q":"Why is Earth's day slowly getting longer?"},{"id":"earth-densest-planet","t":"space","q":"Why is Earth the densest planet in the solar system?"},{"id":"earth-elliptical-orbit","t":"space","q":"Why isn't Earth actually closest to the Sun during summer?"},{"id":"earth-equator-bulge","t":"space","q":"Why is Earth not perfectly round, but slightly squashed?"},{"id":"earth-kept-water","t":"space","q":"Why did Earth manage to keep its water when Venus and Mars couldn't?"},{"id":"earth-magnetic-field","t":"space","q":"Why does Earth have a magnetic field that reaches into space?"},{"id":"earth-moving-plates","t":"space","q":"Why is Earth the only rocky planet with plates that actually move?"},{"id":"earth-nitrogen-air","t":"space","q":"Why is the air we breathe mostly nitrogen, not oxygen?"},{"id":"earthshine","t":"space","q":"Why can you sometimes see the whole dark part of a crescent Moon glowing faintly?"},{"id":"eclipse","t":"space","q":"Why does the Sun go dark in an eclipse?"},{"id":"eclipse-everyone-sees","t":"space","q":"Why can everyone on the night side of Earth see the same lunar eclipse at once?"},{"id":"eht-photo-orange-ring","t":"space","q":"Why did the famous black hole photo show a glowing ring instead of the black hole itself?"},{"id":"einstein-cosmological-constant","t":"space","q":"Why did Einstein call one of his own equations his biggest blunder?"},{"id":"elliptical-no-new-stars","t":"space","q":"Why do elliptical galaxies stop making new stars while spirals keep going?"},{"id":"enceladus-brightest","t":"space","q":"Why is Enceladus one of the whitest, most mirror-like objects in the solar system?"},{"id":"enceladus-feeds-ring","t":"space","q":"Why does one small moon's spray help build one of Saturn's rings?"},{"id":"enceladus-geysers","t":"space","q":"Why does the small moon Enceladus shoot giant jets of water into space?"},{"id":"ergosphere-penrose-process","t":"space","q":"Why can spinning black holes have energy stolen from them without anything crossing the horizon?"},{"id":"europa-few-craters","t":"space","q":"Why does Europa's icy surface have almost no craters on it?"},{"id":"europa-hidden-ocean","t":"space","q":"Why might Europa hold more liquid water than every ocean on Earth?"},{"id":"europa-life-ingredients","t":"space","q":"Why do some scientists think Europa's dark ocean could support life?"},{"id":"europa-red-cracks","t":"space","q":"Why is Europa's icy surface criss-crossed with long reddish-brown cracks?"},{"id":"event-horizon-point-of-no-return","t":"space","q":"Why is a black hole's edge called an \"event horizon\"?"},{"id":"expansion-doesnt-stretch-you","t":"space","q":"Why doesn't the universe's expansion make you, your dog or your house any bigger?"},{"id":"expansion-not-flying-through-space","t":"space","q":"Why doesn't the universe expanding mean galaxies are flying through empty space?"},{"id":"extreme-gravity-redshift","t":"space","q":"Why does light climbing out of a black hole's gravity well turn red before it vanishes?"},{"id":"face-on-edge-on-angle","t":"space","q":"Why do photographs show some galaxies as full spirals and others as thin, straight lines?"},{"id":"farside-discovery","t":"space","q":"Why did nobody see the Moon's far side until 1959?"},{"id":"farside-thick-crust","t":"space","q":"Why is the crust on the Moon's far side thicker than on the near side?"},{"id":"faster-than-light-recession","t":"space","q":"Why can galaxies be moving away from us faster than light without breaking any rules?"},{"id":"fingernail-bruising-glove-pressure","t":"space","q":"Why can wearing a spacesuit glove all day bruise an astronaut's fingernails?"},{"id":"fire-behaves-differently-space","t":"space","q":"Why does fire burn as a round blue ball instead of a flickering flame in space?"},{"id":"fireball-bolide","t":"space","q":"Why do some meteors flare bright enough to light up the ground like daylight?"},{"id":"first-stars-took-millions-of-years","t":"space","q":"Why did it take millions of years for the universe's first stars to switch on?"},{"id":"flare-aurora","t":"space","q":"Why can a solar flare on the Sun light up auroras on Earth?"},{"id":"flare-cause","t":"space","q":"Why do solar flares suddenly blast out so much energy?"},{"id":"flare-satellites","t":"space","q":"Why can a solar flare 150 million kilometres away disable a satellite?"},{"id":"floating-water-balls-cabin","t":"space","q":"Why does spilled water form a wobbly floating ball instead of a puddle in space?"},{"id":"frame-dragging-spinning-black-hole","t":"space","q":"Why does a spinning black hole drag space around with it?"},{"id":"fusion-pressure-needed","t":"space","q":"Why does fusing hydrogen require such crushing pressure and heat?"},{"id":"gaia-enceladus-hidden-merger","t":"space","q":"Why does the Milky Way carry the leftover stars of a galaxy it swallowed ten billion years ago?"},{"id":"galactic-centre-hidden-dust","t":"space","q":"Why can't we actually see our own galaxy's centre with our eyes, even on the clearest night?"},{"id":"galaxies-spin","t":"space","q":"Why do galaxies spin?"},{"id":"galaxy-colour-blue-red","t":"space","q":"Why do spiral galaxies look faintly blue while elliptical galaxies look faintly red?"},{"id":"galaxy-crash","t":"space","q":"Why is another galaxy heading straight for us?"},{"id":"galaxy-missing-dark-matter","t":"space","q":"Why did astronomers find a galaxy that seems to have almost no dark matter at all?"},{"id":"galilean-moons-overturned-earth-centre","t":"space","q":"Why did discovering four moons around Jupiter help prove Earth isn't the centre of everything?"},{"id":"galileo-jupiter-probe","t":"space","q":"Why did a probe dropped into Jupiter only survive for less than an hour?"},{"id":"ganymede-bigger-than-mercury","t":"space","q":"Why is Ganymede bigger than the planet Mercury but still counted as a moon?"},{"id":"ganymede-ice-sandwich-ocean","t":"space","q":"Why might Ganymede have an ocean sandwiched between two layers of ice?"},{"id":"ganymede-own-magnetic-field","t":"space","q":"Why is Ganymede the only moon known to make its own magnetic field?"},{"id":"gas-giant-no-surface-landing","t":"space","q":"Why can't a spacecraft ever land on Jupiter or Saturn?"},{"id":"gas-giants-many-moons","t":"space","q":"Why do Jupiter and Saturn have dozens of moons while Earth has just one?"},{"id":"gas-ice-giant-difference","t":"space","q":"Why are Uranus and Neptune called 'ice giants' instead of 'gas giants' like Jupiter and Saturn?"},{"id":"globular-cluster-ancient","t":"space","q":"Why do globular clusters hold some of the oldest stars in the galaxy?"},{"id":"gravitational-lensing-black-hole","t":"space","q":"Why can a black hole bend the light from stars behind it into rings and arcs?"},{"id":"gravity-golf","t":"space","q":"Why could an astronaut hit a golf ball so much further on the Moon?"},{"id":"gravity-hop","t":"space","q":"Why did Apollo astronauts hop instead of walk normally on the Moon?"},{"id":"gravity-sixth","t":"space","q":"Why is the Moon's gravity only one-sixth as strong as Earth's?"},{"id":"great-attractor-pull","t":"space","q":"Why is something we can't even see pulling our galaxy sideways through space?"},{"id":"great-debate-island-universes","t":"space","q":"Why did astronomers once argue over whether Andromeda was even part of our own galaxy?"},{"id":"growing-plants-space-station","t":"space","q":"Why do astronauts grow lettuce on the space station instead of just packing more food?"},{"id":"haircut-scissors-vacuum-space","t":"space","q":"Why do astronauts get haircuts using scissors attached to a vacuum cleaner?"},{"id":"hayabusa-sample-return","t":"space","q":"Why did a Japanese spacecraft fire a projectile at an asteroid before collecting its sample?"},{"id":"heart-changes-shape-space","t":"space","q":"Why can an astronaut's heart become more rounded after months in orbit?"},{"id":"helioseismology","t":"space","q":"Why do scientists listen to 'sunquakes' rippling across the Sun?"},{"id":"heliosphere-bubble","t":"space","q":"Why does the Sun blow a giant bubble around the whole solar system?"},{"id":"heliosphere-shield","t":"space","q":"Why does the heliosphere protect us from radiation from other stars?"},{"id":"helium-flash","t":"space","q":"Why does a red giant's core detonate in a runaway 'helium flash' nobody outside would notice?"},{"id":"horizon-problem","t":"space","q":"Why do opposite edges of the visible universe seem to know about each other?"},{"id":"hubble-discovered-expansion","t":"space","q":"Why did one astronomer's discovery in the 1920s change how we picture the whole universe?"},{"id":"hubble-tuning-fork-myth","t":"space","q":"Why do astronomers sort galaxies on a diagram shaped like a tuning fork, and why was it misleading?"},{"id":"hunting-primordial-gravitational-waves","t":"space","q":"Why are astronomers hunting for ripples from the Big Bang itself, not just its afterglow?"},{"id":"huygens-titan-landing","t":"space","q":"Why is a probe from 2005 still the only spacecraft to ever land on a moon in the outer solar system?"},{"id":"hypergiant-size","t":"space","q":"Why can a single star be wide enough to swallow the orbit of Saturn?"},{"id":"hypernova-gamma-ray-burst","t":"space","q":"Why can a dying star's final beam of energy be seen across most of the observable universe?"},{"id":"iapetus-two-tone","t":"space","q":"Why is one half of Saturn's moon Iapetus dark as coal and the other bright as snow?"},{"id":"immune-system-weakens-space","t":"space","q":"Why can dormant viruses wake back up inside an astronaut's body in space?"},{"id":"ingenuity-helicopter","t":"space","q":"Why was flying a helicopter on Mars so much harder than flying one on Earth?"},{"id":"intracluster-orphan-stars","t":"space","q":"Why do some stars in a galaxy cluster belong to no galaxy at all?"},{"id":"io-most-volcanic","t":"space","q":"Why is Io the most volcanically active place in the whole solar system?"},{"id":"io-no-craters","t":"space","q":"Why does ancient Io have almost no impact craters despite being billions of years old?"},{"id":"io-pizza-colours","t":"space","q":"Why does Io look blotchy yellow, orange, red and black, like a strange pizza?"},{"id":"io-tidal-squeeze","t":"space","q":"Why do three of Jupiter's moons work together to keep squeezing Io?"},{"id":"ion-engine-not-launch","t":"space","q":"Why can't rockets use super-efficient ion engines to lift off from the ground?"},{"id":"ion-engine-probes","t":"space","q":"Why do some spacecraft use engines that push about as hard as a falling leaf?"},{"id":"irregular-galaxy-shape","t":"space","q":"Why do some galaxies have no proper shape at all?"},{"id":"iss-background-noise-earplugs","t":"space","q":"Why is the space station so noisy that astronauts wear earplugs to sleep?"},{"id":"iss-fast","t":"space","q":"Why does the space station go so fast?"},{"id":"iss-toilet-suction","t":"space","q":"Why does the space station toilet use suction instead of water and gravity?"},{"id":"janus-epimetheus-swap","t":"space","q":"Why do two of Saturn's moons swap orbits with each other every few years?"},{"id":"juno-radiation-vault","t":"space","q":"Why does the Juno spacecraft hide its computer inside a titanium vault?"},{"id":"jupiter-deep-lightning","t":"space","q":"Why does Jupiter's lightning strike mostly near its poles instead of its equator?"},{"id":"jupiter-failed-star-myth","t":"space","q":"Why is it wrong to call Jupiter a 'failed star'?"},{"id":"jupiter-faint-rings","t":"space","q":"Why does Jupiter have rings too faint to notice from Earth?"},{"id":"jupiter-gravity-dominant","t":"space","q":"Why does Jupiter's gravity shape the whole solar system, not just its own moons?"},{"id":"jupiter-inner-heat","t":"space","q":"Why does Jupiter glow with more heat than it gets from the Sun?"},{"id":"jupiter-metallic-hydrogen","t":"space","q":"Why does Jupiter have liquid metal sloshing inside it?"},{"id":"jupiter-not-total-shield","t":"space","q":"Why doesn't Jupiter protect Earth from every asteroid?"},{"id":"jupiter-permanent-aurora","t":"space","q":"Why does Jupiter have auroras that almost never switch off?"},{"id":"jupiter-radio-crackle","t":"space","q":"Why can you pick up Jupiter's crackle on an ordinary radio?"},{"id":"jupiter-red-spot-jr","t":"space","q":"Why did Jupiter grow a second red storm nicknamed 'Red Spot Junior'?"},{"id":"jupiter-red-spot-shrinking","t":"space","q":"Why is Jupiter's Great Red Spot shrinking?"},{"id":"jupiter-shortest-day","t":"space","q":"Why does Jupiter have the shortest day of any planet?"},{"id":"jupiter-squashed-shape","t":"space","q":"Why is Jupiter squashed instead of a perfect ball?"},{"id":"jupiter-stripes","t":"space","q":"Why is Jupiter striped?"},{"id":"jupiter-strongest-magnet","t":"space","q":"Why does Jupiter have the strongest magnetic field of any planet?"},{"id":"jupiter-trojan-asteroids","t":"space","q":"Why do thousands of asteroids share Jupiter's orbit without ever crashing into it?"},{"id":"kidney-stone-risk-bone-calcium","t":"space","q":"Why are astronauts at higher risk of kidney stones during long missions?"},{"id":"kuiper-belt-comets","t":"space","q":"Why do some comets return every few years like clockwork instead of every million years?"},{"id":"laniakea-supercluster","t":"space","q":"Why is our whole galactic neighbourhood just a corner of something far bigger?"},{"id":"launch-delay-wind-shear","t":"space","q":"Why can strong winds high above the launch pad delay a rocket even when it's calm at ground level?"},{"id":"launch-pad-water-deluge","t":"space","q":"Why do launch pads dump hundreds of thousands of litres of water under a rocket right at liftoff?"},{"id":"launch-scrubbed-lightning","t":"space","q":"Why do rocket launches sometimes get called off minutes before liftoff because of weather nowhere near a storm?"},{"id":"light-past","t":"space","q":"Why do we see stars as they were long ago?"},{"id":"ligo-detects-tiny-wobble","t":"space","q":"Why can a gravitational wave detector sense a wobble smaller than a proton?"},{"id":"liquids-need-pouches-straws","t":"space","q":"Why do astronauts drink from sealed pouches through a straw instead of a cup?"},{"id":"local-group-neighbourhood","t":"space","q":"Why does the Milky Way belong to a small neighbourhood of about 80 other galaxies?"},{"id":"lunar-dawn-slow","t":"space","q":"Why does sunrise creep across the Moon so much slower than on Earth?"},{"id":"lunar-day-length","t":"space","q":"Why does one day on the Moon last almost a whole month?"},{"id":"lunar-temp-swing","t":"space","q":"Why can the same spot on the Moon swing between scorching and freezing in a single lunar day?"},{"id":"mag-diaper-spacewalk","t":"space","q":"Why do astronauts wear something like a nappy during a long spacewalk?"},{"id":"magellanic-clouds-naked-eye","t":"space","q":"Why do two fuzzy patches in the southern sky turn out to be entire other galaxies?"},{"id":"magellanic-stream-gas","t":"space","q":"Why do the Magellanic Clouds trail a huge stream of gas behind them across the sky?"},{"id":"magnetar-field","t":"space","q":"Why are magnetars the strongest magnets known anywhere?"},{"id":"magnetar-giant-flare-2004","t":"space","q":"Why did a flash from a magnetar briefly disturb our own atmosphere from 50,000 light years away?"},{"id":"magnetar-vs-pulsar-difference","t":"space","q":"Why are magnetars and pulsars actually the same kind of object playing different roles?"},{"id":"main-sequence-balance","t":"space","q":"Why doesn't a shining star collapse inward or blow itself apart?"},{"id":"maria-nearside-only","t":"space","q":"Why do the dark maria patches cover the near side but barely touch the far side?"},{"id":"maria-seas","t":"space","q":"Why are the Moon's dark patches called seas when they hold no water?"},{"id":"mars-ancient-water","t":"space","q":"Why do scientists think Mars once had rivers and lakes, even though it's bone dry now?"},{"id":"mars-blue-sunset","t":"space","q":"Why is the Martian sky butterscotch by day and blue at sunset, the opposite of Earth's?"},{"id":"mars-climate-orbiter-units","t":"space","q":"Why did a Mars spacecraft burn up because two teams used different units of measurement?"},{"id":"mars-cold-co2","t":"space","q":"Why is Mars still freezing even though its air is almost entirely carbon dioxide?"},{"id":"mars-day-length","t":"space","q":"Why is a day on Mars almost exactly as long as a day on Earth?"},{"id":"mars-fine-dust","t":"space","q":"Why is the dust on Mars finer than talcum powder and impossible to keep out?"},{"id":"mars-global-dust-storm","t":"space","q":"Why can a dust storm on Mars swallow the entire planet?"},{"id":"mars-ice-caps","t":"space","q":"Why do Mars's ice caps grow and shrink with the seasons?"},{"id":"mars-light-gravity","t":"space","q":"Why would you weigh so much less standing on Mars?"},{"id":"mars-lost-magnetism","t":"space","q":"Why doesn't Mars have a global magnetic field, even though it once did?"},{"id":"mars-olympus-mons","t":"space","q":"Why is Mars's biggest volcano so wide you might not notice you're standing on a mountain?"},{"id":"mars-parachute-thin-air","t":"space","q":"Why can't a parachute alone slow a spacecraft down enough to land safely on Mars?"},{"id":"mars-red","t":"space","q":"Why is Mars red?"},{"id":"mars-robots","t":"space","q":"Why do we send robots to Mars instead of people?"},{"id":"mars-rover-autonomous-nav","t":"space","q":"Why do Mars rovers get to make some driving decisions completely on their own?"},{"id":"mars-rover-not-joystick","t":"space","q":"Why can't anyone drive a Mars rover with a joystick in real time?"},{"id":"mars-rover-orbiter-relay","t":"space","q":"Why do Mars rovers usually send their photos to an orbiter overhead instead of straight to Earth?"},{"id":"mars-rovers-many-cameras","t":"space","q":"Why does a single Mars rover carry more than 20 separate cameras?"},{"id":"mars-small-size","t":"space","q":"Why did Mars end up so much smaller than Earth or Venus?"},{"id":"mars-thin-air","t":"space","q":"Why is the air on Mars too thin to breathe, even if it were oxygen?"},{"id":"mars-two-moons","t":"space","q":"Why does Mars have two tiny, lumpy moons instead of one round one?"},{"id":"mars-valles-marineris","t":"space","q":"Why does Mars have a canyon that could swallow Australia's entire east coast?"},{"id":"mass-luminosity-paradox","t":"space","q":"Why do the most massive stars burn through their fuel the fastest, not the slowest?"},{"id":"matter-antimatter-imbalance","t":"space","q":"Why is there hardly any antimatter left in the universe?"},{"id":"maunder-minimum","t":"space","q":"Why did the Sun almost stop making sunspots for 70 years?"},{"id":"megaparsec-distance-unit","t":"space","q":"Why do astronomers measure the distance to other galaxies in megaparsecs, not kilometres?"},{"id":"mercury-big-core","t":"space","q":"Why does tiny Mercury have such an enormous iron core?"},{"id":"mercury-caloris","t":"space","q":"Why does Mercury have a scar bigger than most countries?"},{"id":"mercury-craters","t":"space","q":"Why has Mercury's surface stayed covered in craters for billions of years?"},{"id":"mercury-day-year","t":"space","q":"Why does a day on Mercury last longer than its year?"},{"id":"mercury-exosphere","t":"space","q":"Why doesn't Mercury have a real atmosphere?"},{"id":"mercury-hollows","t":"space","q":"Why does Mercury have strange bright hollows found nowhere else in the solar system?"},{"id":"mercury-magnetic-field","t":"space","q":"Why does small, slow-spinning Mercury still have a magnetic field?"},{"id":"mercury-polar-ice","t":"space","q":"Why is there ice hiding on Mercury, the planet closest to the Sun?"},{"id":"mercury-shrinking","t":"space","q":"Why is Mercury slowly shrinking?"},{"id":"mercury-temp-swings","t":"space","q":"Why does Mercury swing between scorching and freezing in a single day?"},{"id":"merging-galaxy-double-nucleus","t":"space","q":"Why do some merging galaxies briefly have two separate glowing centres?"},{"id":"messier-catalogue-irony","t":"space","q":"Why did a comet hunter end up giving his name to a famous list of galaxies?"},{"id":"meteor-burn","t":"space","q":"Why do shooting stars burn up?"},{"id":"meteor-meteorite-terms","t":"space","q":"Why does the same falling rock get three completely different names?"},{"id":"meteor-shower-origin","t":"space","q":"Why do meteor showers happen on almost the same nights every single year?"},{"id":"meteor-shower-parent-comet","t":"space","q":"Why does a comet keep causing meteor showers years after the comet itself has moved on or even broken apart?"},{"id":"meteor-shower-radiant","t":"space","q":"Why do all the meteors in a shower seem to shoot outward from one patch of sky?"},{"id":"meteor-smoke-train","t":"space","q":"Why do some meteors leave a glowing trail that lingers in the sky for minutes?"},{"id":"meteorite-hunting-antarctica","t":"space","q":"Why do scientists search the ice of Antarctica for meteorites?"},{"id":"meteorite-iron-core","t":"space","q":"Why are some meteorites made almost entirely of solid iron?"},{"id":"meteorite-not-hot","t":"space","q":"Why are most meteorites cool, sometimes even frosty, moments after they land?"},{"id":"meteorite-older-than-earth","t":"space","q":"Why can a meteorite be older than the Earth itself?"},{"id":"meteorite-vs-crater-rarity","t":"space","q":"Why do only a handful of meteorites ever leave a crater when they land?"},{"id":"meteoroid-burn-altitude","t":"space","q":"Why do meteors flash to life at almost exactly the same height above the ground, no matter where you are?"},{"id":"micro-black-holes-lhc-safe","t":"space","q":"Why weren't scientists worried a giant science experiment might create a black hole that eats Earth?"},{"id":"milky-way","t":"space","q":"Why is the Milky Way a stripe?"},{"id":"milky-way-bulge","t":"space","q":"Why does the Milky Way have a fat bulge of stars at its centre?"},{"id":"milky-way-disc-warp","t":"space","q":"Why is the Milky Way's disc bent instead of perfectly flat?"},{"id":"milky-way-halo","t":"space","q":"Why is the Milky Way's disc surrounded by a huge, almost empty sphere of stars?"},{"id":"milky-way-orion-spur","t":"space","q":"Why does Earth sit in a minor spur of a spiral arm rather than a major one?"},{"id":"milky-way-star-count","t":"space","q":"Why don't astronomers know the exact number of stars in the Milky Way?"},{"id":"mimas-giant-crater","t":"space","q":"Why does Saturn's small moon Mimas have one crater almost big enough to have broken it apart?"},{"id":"miranda-patchwork-cliffs","t":"space","q":"Why does Uranus's small moon Miranda look stitched together from mismatched patches?"},{"id":"mobile-launch-platforms-sea","t":"space","q":"Why do some rockets launch from floating platforms out at sea instead of solid ground?"},{"id":"moon-craters","t":"space","q":"Why is the Moon covered in craters?"},{"id":"moon-daytime","t":"space","q":"Why can you sometimes see the Moon in the middle of the day?"},{"id":"moon-drifting-away","t":"space","q":"Why is the Moon slowly moving away from Earth?"},{"id":"moon-fall","t":"space","q":"Why doesn't the Moon fall down?"},{"id":"moon-illusion","t":"space","q":"Why does a full Moon look huge near the horizon but small overhead?"},{"id":"moon-magma-ocean","t":"space","q":"Why was the young Moon once covered in an ocean of molten rock?"},{"id":"moon-one-side","t":"space","q":"Why do we only ever see one side of the Moon?"},{"id":"moon-origin","t":"space","q":"Why does Earth have a Moon?"},{"id":"moon-rock-twin","t":"space","q":"Why is Moon rock so chemically similar to Earth's outer layers?"},{"id":"moon-rocket-more-fuel","t":"space","q":"Why does reaching the Moon take so much more fuel than just reaching orbit around Earth?"},{"id":"moon-shape","t":"space","q":"Why does the Moon change shape?"},{"id":"moon-tiny-core","t":"space","q":"Why does the Moon have such a small metal core compared to Earth's?"},{"id":"moondust-sharp","t":"space","q":"Why is Moon dust dangerously sharp instead of soft like beach sand?"},{"id":"moondust-static","t":"space","q":"Why does Moon dust cling to everything like static-charged glitter?"},{"id":"moondust-suits","t":"space","q":"Why did Moon dust wear holes in astronauts' spacesuits within days?"},{"id":"moonlight-delay","t":"space","q":"Why is moonlight already about 1.3 seconds old by the time it reaches your eyes?"},{"id":"moonlight-grey-not-silver","t":"space","q":"Why does moonlight look silvery-blue even though it's really just dull grey sunlight?"},{"id":"moonlight-not-warm","t":"space","q":"Why doesn't moonlight warm your skin, even on a bright full-moon night?"},{"id":"moonquake-monthly","t":"space","q":"Why do some moonquakes strike in the same spot like clockwork every month?"},{"id":"moonquake-ring","t":"space","q":"Why does the Moon ring like a bell during a moonquake instead of just shaking?"},{"id":"moonquake-seismometers","t":"space","q":"Why did instruments left on the Moon keep recording quakes for years after the astronauts went home?"},{"id":"moonrise-later","t":"space","q":"Why does the Moon rise about 50 minutes later every night?"},{"id":"moons-round-vs-lumpy","t":"space","q":"Why are some moons perfectly round while others, like Phobos, stay lumpy potato shapes?"},{"id":"moxie-oxygen","t":"space","q":"Why did a box the size of a toaster try to make oxygen out of Martian air?"},{"id":"multistage-more-efficient","t":"space","q":"Why do rockets with more stages generally reach orbit more efficiently than rockets with fewer?"},{"id":"multiverse-idea","t":"space","q":"Why do some scientists think our universe might not be the only one?"},{"id":"muscle-loss-microgravity","t":"space","q":"Why do astronauts' muscles waste away if they just float around all day?"},{"id":"myth-not-all-black-holes","t":"space","q":"Why doesn't every dying star end up as a black hole?"},{"id":"near-earth-tracking","t":"space","q":"Why do astronomers spend every night carefully tracking asteroids that pass near Earth?"},{"id":"neptune-cold-despite-heat","t":"space","q":"Why is Neptune bitterly cold, even though it makes more of its own heat than any other planet?"},{"id":"neptune-dark-spot-vanished","t":"space","q":"Why did Neptune's giant dark storm disappear just a few years after it was found?"},{"id":"neptune-fastest-winds","t":"space","q":"Why does Neptune have the fastest winds in the whole solar system?"},{"id":"neptune-first-orbit-2011","t":"space","q":"Why did Neptune only complete its first lap of the Sun in 2011, since being discovered in 1846?"},{"id":"neptune-ring-arcs","t":"space","q":"Why do parts of Neptune's rings look bunched into clumps instead of spreading evenly?"},{"id":"neptune-tilt-normal","t":"space","q":"Why does Neptune have an ordinary tilt while its neighbour Uranus lies on its side?"},{"id":"neptune-vivid-blue","t":"space","q":"Why does Neptune look a much deeper blue than Uranus, even though both have methane?"},{"id":"nereid-stretched-orbit","t":"space","q":"Why does Neptune's moon Nereid follow one of the most stretched-out orbits of any moon?"},{"id":"neutron-star-crust-quake","t":"space","q":"Why can a crack in a neutron star's crust be detected all the way across the galaxy?"},{"id":"neutron-star-crust-strongest-material","t":"space","q":"Why is a neutron star's crust the strongest material known to science?"},{"id":"neutron-star-density","t":"space","q":"Why can a neutron star pack more mass than the Sun into a ball the size of a city?"},{"id":"neutron-star-glitches","t":"space","q":"Why do neutron stars sometimes suddenly speed up their spin in a \"glitch\"?"},{"id":"neutron-star-merger-kilonova","t":"space","q":"Why did colliding neutron stars once light up the sky as a 'kilonova'?"},{"id":"neutron-star-spin-fast","t":"space","q":"Why can a neutron star spin hundreds of times in a single second?"},{"id":"new-horizons-arrokoth","t":"space","q":"Why did a spacecraft fly past a tiny frozen world more than a billion kilometres beyond Pluto?"},{"id":"new-horizons-pluto","t":"space","q":"Why did it take nine and a half years for a spacecraft to fly past Pluto?"},{"id":"night-sky-dark-paradox","t":"space","q":"Why isn't the whole night sky as bright as the surface of a star?"},{"id":"no-centre-of-universe","t":"space","q":"Why doesn't the universe have a centre?"},{"id":"no-crumbly-bread-space","t":"space","q":"Why do astronauts eat tortillas instead of ordinary bread in space?"},{"id":"no-dark-side","t":"space","q":"Why is there no such thing as a permanently dark side of the Moon?"},{"id":"no-hair-theorem","t":"space","q":"Why do astronomers say a black hole has \"no hair\"?"},{"id":"no-sound-in-big-bang","t":"space","q":"Why couldn't anyone have actually heard the Big Bang happen?"},{"id":"no-sound-space","t":"space","q":"Why can't you hear anything in space?"},{"id":"no-sunset-orbit","t":"space","q":"Why do astronauts see a sunrise every 90 minutes?"},{"id":"observable-universe-limit","t":"space","q":"Why can we only ever see part of the whole universe?"},{"id":"oort-cloud","t":"space","q":"Why do some comets take millions of years to complete a single orbit?"},{"id":"opportunity-solar-dust","t":"space","q":"Why did a Mars dust storm end the Opportunity rover's mission after almost 15 years?"},{"id":"orbit-is-falling","t":"space","q":"Why is a satellite in orbit really just falling, instead of having escaped Earth's gravity?"},{"id":"orbit-need-sideways-speed","t":"space","q":"Why does staying in orbit depend on speed sideways, not height above the ground?"},{"id":"orthostatic-intolerance-return","t":"space","q":"Why do astronauts sometimes nearly faint the first time they stand after landing?"},{"id":"osiris-rex-sample","t":"space","q":"Why did a spacecraft touch an asteroid for only a few seconds to collect its sample?"},{"id":"pan-ravioli-ridge","t":"space","q":"Why does Saturn's tiny moon Pan look like a flying saucer or a piece of ravioli?"},{"id":"payload-fairing-jettison","t":"space","q":"Why does the pointed nose cone on a rocket fall away partway through the flight?"},{"id":"permanent-shadow","t":"space","q":"Why do some craters near the Moon's poles never once see sunlight?"},{"id":"perseverance-name-contest","t":"space","q":"Why was NASA's newest Mars rover named by a middle schooler instead of a scientist?"},{"id":"philae-bounce","t":"space","q":"Why did a comet lander bounce back off the surface instead of just sticking to it?"},{"id":"phobos-fast-orbit","t":"space","q":"Why does Mars's moon Phobos rise in the west and set in the east?"},{"id":"pioneer-plaque","t":"space","q":"Why did NASA's Pioneer probes carry a metal plaque showing a naked man and woman?"},{"id":"planck-time-limit","t":"space","q":"Why can't physicists describe the universe's very first sliver of a second?"},{"id":"planetary-protection-sterilize","t":"space","q":"Why do engineers bake some spacecraft in ovens before launching them to other worlds?"},{"id":"planets-round","t":"space","q":"Why are planets round?"},{"id":"pleiades-seven-sisters","t":"space","q":"Why are the Pleiades called the Seven Sisters when far more stars are actually there?"},{"id":"pluto","t":"space","q":"Why isn't Pluto a planet any more?"},{"id":"pluto-charon-double-system","t":"space","q":"Why do Pluto and its moon Charon act more like a double planet than a planet and moon?"},{"id":"polar-ice","t":"space","q":"Why is there ice hiding on the Moon, a place with no water cycle at all?"},{"id":"population-metallicity-age","t":"space","q":"Why can a star's chemical makeup reveal whether it is ancient or young?"},{"id":"prebreathe-decompression-sickness","t":"space","q":"Why do astronauts breathe pure oxygen for hours before a spacewalk?"},{"id":"primordial-black-holes-hypothetical","t":"space","q":"Why do some scientists think tiny black holes might have formed moments after the Big Bang?"},{"id":"protostar-disk-feeding","t":"space","q":"Why does a newborn star keep growing by pulling in gas from a spinning disk around it?"},{"id":"protostar-glow","t":"space","q":"Why does a brand new star glow warm long before fusion ever switches on inside it?"},{"id":"puffy-face-bird-legs","t":"space","q":"Why do astronauts get puffy faces and skinny-looking legs in space?"},{"id":"pulsar-lighthouse","t":"space","q":"Why do some neutron stars seem to blink on and off like a lighthouse?"},{"id":"quarantine-before-launch","t":"space","q":"Why are astronauts kept in quarantine for days before launching into space?"},{"id":"quark-star-hypothetical","t":"space","q":"Why do some scientists think an even stranger kind of star than a neutron star might exist?"},{"id":"quasar-brightest-objects","t":"space","q":"Why can a quasar outshine an entire galaxy of stars?"},{"id":"quenched-red-dead-galaxy","t":"space","q":"Why do some big galaxies stop making stars completely and just fade?"},{"id":"radiation-exposure-higher-space","t":"space","q":"Why do astronauts absorb far more radiation in orbit than people do on Earth?"},{"id":"radio-gas-disc-bigger","t":"space","q":"Why do radio telescope images show galaxies far bigger than ordinary photographs do?"},{"id":"red-dwarf-common-invisible","t":"space","q":"Why is the most common type of star in the galaxy one you've probably never seen?"},{"id":"redshift-expansion-clue","t":"space","q":"Why does the colour of far-off galaxies reveal that the universe is expanding?"},{"id":"redshift-vs-doppler-myth","t":"space","q":"Why isn't a distant galaxy's redshift quite the same thing as an ambulance siren's pitch change?"},{"id":"regular-vs-irregular-moons","t":"space","q":"Why do astronomers sort moons into two groups called regular and irregular?"},{"id":"reusable-rocket-landing","t":"space","q":"Why can some rockets fly themselves back down and land standing up instead of falling into the ocean?"},{"id":"rhea-maybe-rings","t":"space","q":"Why did scientists once think Saturn's moon Rhea might have its own tiny ring system?"},{"id":"rocket-countdown","t":"space","q":"Why does every rocket launch count down instead of just lifting off when it's ready?"},{"id":"rocket-equation-diminishing-returns","t":"space","q":"Why can't rockets just keep getting bigger and bigger to carry more and more cargo?"},{"id":"rocket-escape-velocity","t":"space","q":"Why does a rocket need to reach 11.2 kilometres a second to leave Earth for good?"},{"id":"rocket-exhaust-plume-vacuum","t":"space","q":"Why does a rocket's exhaust plume look completely different once it's flying above the atmosphere?"},{"id":"rocket-fins-useless-space","t":"space","q":"Why do some rockets have fins near the bottom, and why don't spacecraft need them once they're off the ground?"},{"id":"rocket-first-stage-hardest-work","t":"space","q":"Why does a rocket's biggest, most powerful stage only fly for a couple of minutes?"},{"id":"rocket-flame-colour","t":"space","q":"Why do rocket engine flames glow different colours, from orange to almost clear blue?"},{"id":"rocket-fuel-choices","t":"space","q":"Why do different rockets burn completely different fuels, from kerosene to hydrogen?"},{"id":"rocket-fuel-supercooled","t":"space","q":"Why do some rockets get chilled to freezing temperatures right before launch on a warm day?"},{"id":"rocket-gravity-turn","t":"space","q":"Why do rockets tip over onto their sides on the way up instead of flying straight to space?"},{"id":"rocket-launch-near-equator","t":"space","q":"Why are so many rocket launch sites built close to the equator?"},{"id":"rocket-launch-over-ocean","t":"space","q":"Why are so many rocket launch sites built on coastlines, aimed out over open ocean?"},{"id":"rocket-launch-so-loud","t":"space","q":"Why is a rocket launch loud enough to be felt in your chest kilometres away?"},{"id":"rocket-launch-windows","t":"space","q":"Why do some rockets have to launch during a very specific few minutes, called a launch window?"},{"id":"rocket-max-q","t":"space","q":"Why do rocket engines briefly throttle down partway through launch instead of staying at full power?"},{"id":"rocket-mostly-fuel","t":"space","q":"Why is a giant rocket on the launch pad mostly just fuel?"},{"id":"rocket-needs-oxidiser","t":"space","q":"Why do rockets carry their own oxygen instead of using air like a jet engine?"},{"id":"rocket-not-explode","t":"space","q":"Why doesn't a rocket engine just explode like a bomb, when it burns fuel just as fiercely?"},{"id":"rocket-nozzle-bell-shape","t":"space","q":"Why do rocket engines end in a wide, flared bell shape instead of a plain pipe?"},{"id":"rocket-push-vacuum","t":"space","q":"Why can a rocket move in the empty vacuum of space if there's nothing to push against?"},{"id":"rocket-stages-shed-weight","t":"space","q":"Why do rockets fall apart into pieces on the way up instead of flying as one whole machine?"},{"id":"rocket-static-fire-test","t":"space","q":"Why do some rockets fire their engines on the launch pad days before the actual launch, without going anywhere?"},{"id":"rocket-thrust-to-weight","t":"space","q":"Why does a rocket need engines strong enough to more than double its own weight in pushing power?"},{"id":"rocket-tips-over-if-unstable","t":"space","q":"Why does a rocket need its heaviest parts near the nose to fly straight instead of tumbling?"},{"id":"rocket-turbopumps","t":"space","q":"Why do rocket engines need powerful pumps just to move their own fuel?"},{"id":"rocket-vapour-cone","t":"space","q":"Why does a white cloud sometimes flash around a rocket partway through its climb on a humid day?"},{"id":"rocket-vibration-shakes-buildings","t":"space","q":"Why can a rocket launch make windows rattle in houses kilometres from the pad?"},{"id":"rocky-planets-small","t":"space","q":"Why are Mercury, Venus, Earth and Mars small and squeezed in close to the Sun?"},{"id":"rogue-wandering-black-holes","t":"space","q":"Why might a black hole wander through the galaxy with no visible companion star?"},{"id":"rosetta-comet-chase","t":"space","q":"Why did a comet-chasing spacecraft need ten years and several planet flybys just to catch up?"},{"id":"rover-wheels-wear","t":"space","q":"Why do Curiosity's metal wheels get holes and tears from ordinary Martian rocks?"},{"id":"rtg-plutonium-power","t":"space","q":"Why do probes exploring the outer solar system carry a lump of radioactive metal instead of batteries?"},{"id":"sagittarius-dwarf-eaten","t":"space","q":"Why is the Milky Way slowly tearing apart a small galaxy right now?"},{"id":"salt-pepper-liquid-form-space","t":"space","q":"Why do astronauts season their food with liquid salt and pepper instead of shakers?"},{"id":"same-clothes-days-space","t":"space","q":"Why do astronauts wear the same clothes for days or weeks at a time?"},{"id":"sample-return-asteroid","t":"space","q":"Why did scientists want to bring a scoop of asteroid dust back to Earth instead of just studying pictures?"},{"id":"satellite-galaxy-plane-puzzle","t":"space","q":"Why do the Milky Way's small satellite galaxies orbit in a strangely thin, flat plane?"},{"id":"saturn-fierce-winds","t":"space","q":"Why does Saturn have winds four times fiercer than Earth's strongest hurricanes?"},{"id":"saturn-helium-rain","t":"space","q":"Why does helium literally rain down inside Saturn?"},{"id":"saturn-hexagon-pole","t":"space","q":"Why does Saturn have a six-sided storm at its north pole?"},{"id":"saturn-magnetic-axis-lined-up","t":"space","q":"Why is Saturn's magnetic field lined up almost exactly with its spin?"},{"id":"saturn-most-flattened","t":"space","q":"Why is Saturn the most flattened planet in the solar system?"},{"id":"saturn-pale-haze","t":"space","q":"Why does Saturn look pale and calm when Jupiter looks bold and stormy?"},{"id":"saturn-ring-plane-vanish","t":"space","q":"Why do Saturn's rings seem to disappear every fifteen years or so?"},{"id":"saturn-rings","t":"space","q":"Why does Saturn have rings?"},{"id":"saturn-rings-young-debate","t":"space","q":"Why do some scientists think Saturn's rings might be surprisingly young?"},{"id":"saturn-storm-great-white-spot","t":"space","q":"Why does a giant white storm erupt on Saturn roughly once every Saturn year?"},{"id":"saturn-would-float","t":"space","q":"Why would Saturn float if you dropped it into an ocean big enough?"},{"id":"saturn-year-length-kepler","t":"space","q":"Why does one year on Saturn last almost thirty Earth years?"},{"id":"seven-minutes-of-terror","t":"space","q":"Why do NASA engineers call a Mars landing the 'seven minutes of terror'?"},{"id":"sgr-a-star-not-sucking-galaxy","t":"space","q":"Why isn't the black hole at our galaxy's centre sucking in the whole Milky Way?"},{"id":"sgra-star-orbits-proved-black-hole","t":"space","q":"Why did watching stars race around the Milky Way's centre prove a black hole is hiding there?"},{"id":"shepherd-moons-rings","t":"space","q":"Why don't Saturn's rings just spread out and disappear over time?"},{"id":"sirius-b-companion","t":"space","q":"Why does the night sky's brightest star drag along a dim, dead companion that went unnoticed for decades?"},{"id":"sky-crane-landing","t":"space","q":"Why did Curiosity land on Mars hanging underneath a hovering rocket-powered crane?"},{"id":"sleeping-bag-wall-space","t":"space","q":"Why do astronauts sleep strapped into a bag stuck to a wall instead of a bed?"},{"id":"small-rockets-cant-reach-orbit","t":"space","q":"Why can't a small home-made rocket ever reach orbit, no matter how well it's built?"},{"id":"smooth-to-clumpy-universe","t":"space","q":"Why did the smooth, even early universe end up clumped into galaxies?"},{"id":"sojourner-name","t":"space","q":"Why was NASA's first Mars rover named after a woman who never left Earth?"},{"id":"solar-cycle-11","t":"space","q":"Why does the Sun's activity rise and fall every eleven years?"},{"id":"solar-poles-flip","t":"space","q":"Why do the Sun's magnetic poles swap places every solar cycle?"},{"id":"solar-wind","t":"space","q":"Why does the Sun send out a constant wind, even though there's no air?"},{"id":"solid-booster-cant-stop","t":"space","q":"Why can't a solid rocket booster be switched off once it's lit?"},{"id":"sombrero-dust-lane","t":"space","q":"Why does the Sombrero Galaxy have a dark ring circling its glowing centre?"},{"id":"sound-silent-outside-suit","t":"space","q":"Why can astronauts talk normally inside the station but hear nothing outside it?"},{"id":"space-anemia","t":"space","q":"Why do astronauts end up with fewer red blood cells after time in space?"},{"id":"space-black","t":"space","q":"Why is space black?"},{"id":"space-cold","t":"space","q":"Why is space cold if there's nothing in it?"},{"id":"space-motion-sickness-early-days","t":"space","q":"Why do many astronauts feel queasy during their first days in orbit?"},{"id":"spacesuit-cooling-garment-layer","t":"space","q":"Why do astronauts wear a suit full of water tubes underneath their spacesuit?"},{"id":"spacesuit-pressurised-body","t":"space","q":"Why do spacesuits have to be pressurised like a small personal spacecraft?"},{"id":"spacesuit-white-colour","t":"space","q":"Why are the big spacewalking spacesuits almost always bright white?"},{"id":"spaghettification-depends-on-size","t":"space","q":"Why would falling into a small black hole stretch you into spaghetti, but a giant one wouldn't?"},{"id":"spiral-arms-density-wave","t":"space","q":"Why don't spiral galaxy arms wind up tighter and tighter over billions of years?"},{"id":"sporadic-meteors","t":"space","q":"Why do you sometimes see a meteor on an ordinary night with no shower happening at all?"},{"id":"star-birth-collapse","t":"space","q":"Why does a gas cloud need to reach a certain thickness before gravity can turn it into a star?"},{"id":"star-birth-nebula","t":"space","q":"Why do new stars form inside vast clouds of gas and dust?"},{"id":"star-clusters-siblings","t":"space","q":"Why are stars usually born in groups rather than alone?"},{"id":"star-colours","t":"space","q":"Why aren't all stars the same colour?"},{"id":"star-fate-by-mass","t":"space","q":"Why does a star's mass, not its brightness, decide how it will die?"},{"id":"star-ignition-threshold","t":"space","q":"Why is there a minimum mass a clump of gas must reach before it can ignite as a star?"},{"id":"star-nursery-orion","t":"space","q":"Why is the Orion Nebula considered a nursery for baby stars?"},{"id":"star-spectral-classes","t":"space","q":"Why do astronomers sort stars using the odd letter order O B A F G K M?"},{"id":"starburst-galaxy-mergers","t":"space","q":"Why do some galaxies burst into forming stars at a furious, hurried rate?"},{"id":"stars-seasons","t":"space","q":"Why do we see different stars in summer and winter?"},{"id":"stars-twinkle","t":"space","q":"Why do stars twinkle?"},{"id":"steady-state-theory-lost","t":"space","q":"Why did scientists once think the universe never had a beginning at all?"},{"id":"stellar-wind-clears-nursery","t":"space","q":"Why do young stars eventually blow away the very cloud that made them?"},{"id":"sun-axis-tilt","t":"space","q":"Why is the Sun tilted compared to the planets circling it?"},{"id":"sun-becomes-black-hole-same-pull","t":"space","q":"Why wouldn't Earth's orbit change if the Sun suddenly became a black hole?"},{"id":"sun-colour-white","t":"space","q":"Why is the Sun actually white, not yellow?"},{"id":"sun-corona","t":"space","q":"Why is the air above the Sun hotter than the Sun?"},{"id":"sun-differential-rotation","t":"space","q":"Why does the Sun's equator spin faster than its poles?"},{"id":"sun-eye-damage","t":"space","q":"Why can looking at the Sun harm your eyes before you feel any pain?"},{"id":"sun-fuel","t":"space","q":"Why doesn't the Sun run out?"},{"id":"sun-halo-space","t":"space","q":"Why does the Sun look like a harsh white dot in space, with no glow around it?"},{"id":"sun-heavy-elements-rare","t":"space","q":"Why does the Sun have so little of anything heavier than helium?"},{"id":"sun-hydrogen-helium","t":"space","q":"Why is the Sun made almost entirely of hydrogen and helium?"},{"id":"sun-mass-share","t":"space","q":"Why does the Sun hold almost all the mass in the solar system?"},{"id":"sun-medium-star","t":"space","q":"Why is the Sun only a medium-sized star?"},{"id":"sun-melt-before-close","t":"space","q":"Why would a spacecraft melt long before it ever reached the Sun?"},{"id":"sun-million-earths","t":"space","q":"Why could over a million Earths fit inside the Sun?"},{"id":"sun-nebula-glow","t":"space","q":"Why will the gas the Sun sheds one day glow as a colourful cloud?"},{"id":"sun-no-oxygen","t":"space","q":"Why can the Sun shine without a scrap of oxygen nearby?"},{"id":"sun-no-surface","t":"space","q":"Why is there no solid ground to land a spacecraft on the Sun?"},{"id":"sun-not-fire","t":"space","q":"Why doesn't the Sun actually burn like a bonfire?"},{"id":"sun-plasma","t":"space","q":"Why is the Sun neither a solid, a liquid nor a gas?"},{"id":"sun-red-giant","t":"space","q":"Why will the Sun swell into a red giant one day?"},{"id":"sun-red-sunset-space","t":"space","q":"Why does a setting Sun turn red on Earth but stay white in space?"},{"id":"sun-special-telescopes","t":"space","q":"Why do astronomers need special telescopes just to look at the Sun?"},{"id":"sun-spectroscopy","t":"space","q":"Why can scientists know what the Sun's made of without ever touching it?"},{"id":"sun-surface-gravity","t":"space","q":"Why would you weigh 28 times more if you stood on the Sun?"},{"id":"sun-swallow-planets","t":"space","q":"Why might the Sun's red giant stage swallow Mercury and Venus?"},{"id":"sun-white-dwarf-fate","t":"space","q":"Why will the Sun shrink into a white dwarf instead of exploding?"},{"id":"sun-yellow-from-ground","t":"space","q":"Why does the Sun look yellow from the ground on Earth?"},{"id":"sungrazing-comets","t":"space","q":"Why do some comets dive-bomb straight into the Sun?"},{"id":"sunspot-crawl","t":"space","q":"Why do sunspots crawl slowly across the Sun over about two weeks?"},{"id":"sunspot-dark","t":"space","q":"Why do sunspots look dark on the Sun's bright face?"},{"id":"sunspot-mistaken","t":"space","q":"Why did old sky-watchers once mistake a sunspot for a tiny planet?"},{"id":"sunspot-pairs","t":"space","q":"Why do sunspots almost always come in pairs?"},{"id":"supermassive-black-holes-galaxy-hearts","t":"space","q":"Why do astronomers think most large galaxies, including ours, keep a supermassive black hole at their heart?"},{"id":"supernova-core-collapse","t":"space","q":"Why does a massive star's core suddenly collapse in well under a second?"},{"id":"supernova-iron-drain","t":"space","q":"Why does fusing iron drain a star's energy instead of releasing more?"},{"id":"supernova-neutrino-head-start","t":"space","q":"Why do the neutrinos from an exploding star race ahead of its light by hours?"},{"id":"supernova-nucleosynthesis","t":"space","q":"Why do exploding stars scatter elements heavier than iron across space?"},{"id":"supernova-outshine-galaxy","t":"space","q":"Why can one exploding star briefly outshine its entire galaxy?"},{"id":"supernova-remnant-crab","t":"space","q":"Why is the Crab Nebula the wreckage of a star people watched explode in 1054?"},{"id":"t-tauri-flicker","t":"space","q":"Why do brand new stars flicker unpredictably before settling into a steady shine?"},{"id":"taste-smell-dulled-space","t":"space","q":"Why do astronauts pile on hot sauce because space food tastes bland?"},{"id":"tears-dont-fall-space","t":"space","q":"Why do tears just stick to an astronaut's face instead of rolling down it?"},{"id":"telescope-adaptive-optics-laser","t":"space","q":"Why do some telescopes fire an orange laser into the sky before observing?"},{"id":"telescope-antarctica-clear-air","t":"space","q":"Why do some astronomers build telescopes at the freezing South Pole?"},{"id":"telescope-aperture-not-magnification","t":"space","q":"Why is a telescope's real job to collect light, not to zoom in?"},{"id":"telescope-arecibo-natural-bowl","t":"space","q":"Why was one of the world's most famous radio telescopes built into a natural sinkhole?"},{"id":"telescope-atacama-desert-site","t":"space","q":"Why has Chile's driest desert become the world's astronomy capital?"},{"id":"telescope-atmosphere-blur-any-size","t":"space","q":"Why does even the biggest ground telescope still fight blurry air?"},{"id":"telescope-backyard-beats-old-giants","t":"space","q":"Why can a keen amateur's backyard telescope now outperform a famous observatory from a century ago?"},{"id":"telescope-binoculars-two-eyes-advantage","t":"space","q":"Why do many astronomers recommend binoculars over a telescope for beginners?"},{"id":"telescope-chromatic-aberration-newton","t":"space","q":"Why did a coloured smear around stars push Isaac Newton to invent a new telescope?"},{"id":"telescope-different-wavelength-different-picture","t":"space","q":"Why can the exact same object in the sky look completely different through different kinds of telescopes?"},{"id":"telescope-digital-sensor-replaced-film","t":"space","q":"Why did astronomers abandon glass photographic plates for digital sensors?"},{"id":"telescope-dome-cooling-before-night","t":"space","q":"Why do astronomers cool an observatory dome down before the Sun even sets?"},{"id":"telescope-dome-slit-not-roof","t":"space","q":"Why do observatory domes open with a narrow slit instead of a full roof?"},{"id":"telescope-exoplanet-coronagraph-block-star","t":"space","q":"Why do some telescopes deliberately block out a star's light to find a planet?"},{"id":"telescope-exoplanet-transit-dimming","t":"space","q":"Why can a telescope detect a planet around another star without ever actually seeing it?"},{"id":"telescope-false-colour-images","t":"space","q":"Why are so many stunning space telescope photos actually painted in colours that aren't really there?"},{"id":"telescope-focal-length-magnification","t":"space","q":"Why does a telescope's length, not just its width, change how much it magnifies?"},{"id":"telescope-galileo-first-use","t":"space","q":"Why did a toy from Dutch spectacle-makers end up rewriting astronomy?"},{"id":"telescope-hubble-deep-field-empty-patch","t":"space","q":"Why did astronomers point Hubble at a seemingly empty patch of sky for ten straight days?"},{"id":"telescope-hubble-in-space-not-bigger","t":"space","q":"Why did astronomers launch Hubble into space instead of just building a bigger telescope on the ground?"},{"id":"telescope-hubble-mirror-flaw-fixed","t":"space","q":"Why were Hubble's first photos disappointingly blurry, and how did astronauts fix a space telescope without bringing it home?"},{"id":"telescope-icecube-neutrino-ice","t":"space","q":"Why does one 'telescope' use a cubic kilometre of Antarctic ice instead of any lens or dish at all?"},{"id":"telescope-jansky-accidental-radio-discovery","t":"space","q":"Why did an engineer chasing a mysterious radio hiss accidentally invent radio astronomy?"},{"id":"telescope-jwst-infrared-not-visible","t":"space","q":"Why does the James Webb Space Telescope see in infrared instead of visible light like Hubble?"},{"id":"telescope-jwst-l2-far-orbit","t":"space","q":"Why does the James Webb Space Telescope orbit far past the Moon instead of close to Earth like Hubble?"},{"id":"telescope-jwst-must-stay-cold","t":"space","q":"Why does the James Webb Space Telescope need to stay colder than anywhere on Earth?"},{"id":"telescope-jwst-segmented-gold-mirror","t":"space","q":"Why is the James Webb Space Telescope's mirror built from 18 gold hexagons instead of one solid disc?"},{"id":"telescope-light-pollution-avoid-cities","t":"space","q":"Why do professional telescopes avoid cities almost entirely?"},{"id":"telescope-long-exposure-stacking","t":"space","q":"Why do astronomers combine dozens of short photos into one instead of taking a single long one?"},{"id":"telescope-magnification-marketing-myth","t":"space","q":"Why should you ignore a cheap telescope box that boasts huge magnification?"},{"id":"telescope-mirror-precision-wavelength","t":"space","q":"Why must a telescope mirror be polished almost impossibly smooth?"},{"id":"telescope-mirror-vs-lens-size","t":"space","q":"Why do the biggest telescopes use mirrors instead of giant glass lenses?"},{"id":"telescope-mount-tracking-motor","t":"space","q":"Why do serious telescopes need a motor just to stay pointed at one star?"},{"id":"telescope-nebula-photo-vs-eye","t":"space","q":"Why don't glowing nebula photos look anything like what your eye would actually see through a telescope?"},{"id":"telescope-objective-vs-eyepiece-roles","t":"space","q":"Why does a telescope actually need two separate lenses or mirrors working together, not just one?"},{"id":"telescope-radio-dish-shape","t":"space","q":"Why do radio telescopes look like giant dishes instead of tubes with glass?"},{"id":"telescope-radio-interferometer-array","t":"space","q":"Why do astronomers link dozens of separate radio dishes together instead of building one giant one?"},{"id":"telescope-radio-need-huge-size","t":"space","q":"Why must radio telescopes be so much bigger than optical ones to see the same fine detail?"},{"id":"telescope-site-remote-mountains","t":"space","q":"Why do the world's best telescopes sit on remote mountaintops?"},{"id":"telescope-spectral-filters-narrowband","t":"space","q":"Why do astronomers photograph glowing gas clouds through filters that block almost all colours?"},{"id":"telescope-submillimetre-dry-site-needed","t":"space","q":"Why do telescopes hunting for the coldest, faintest cosmic light need bone-dry air above them?"},{"id":"telescope-uv-blocked-needs-space","t":"space","q":"Why can astronomers only study most ultraviolet starlight from space?"},{"id":"telescope-vlbi-earth-sized-network","t":"space","q":"Why did photographing a black hole need a network of telescopes spread across the whole planet?"},{"id":"telescope-xray-grazing-incidence-mirrors","t":"space","q":"Why can't an X-ray telescope use an ordinary curved mirror like an optical one?"},{"id":"telescope-xray-must-fly-in-space","t":"space","q":"Why must telescopes that study X-rays fly in space instead of sitting on the ground?"},{"id":"temperature-extremes-station-sides","t":"space","q":"Why can one side of the space station be scorching while the other side freezes?"},{"id":"tethered-tools-spacewalk","t":"space","q":"Why is every tool an astronaut uses outside tied on with a tether?"},{"id":"tidal-disruption-event","t":"space","q":"Why does a black hole ripping apart a star create a flare astronomers can spot from billions of light years away?"},{"id":"tidal-heating-far-from-sun","t":"space","q":"Why can icy moons far from the Sun still have warm, liquid interiors?"},{"id":"tidal-tail-streamers","t":"space","q":"Why do colliding galaxies grow long streamers of stars flung out sideways?"},{"id":"time-began-question","t":"space","q":"Why might asking what came before time itself not even make sense?"},{"id":"tiny-black-hole-evaporates-fast","t":"space","q":"Why would a black hole the mass of a mountain flash out of existence, while a giant one outlives the universe?"},{"id":"titan-hidden-ocean","t":"space","q":"Why do scientists think Titan hides a salty ocean under all that ice?"},{"id":"titan-methane-lakes","t":"space","q":"Why does Titan have rivers and lakes but no liquid water in them?"},{"id":"titan-orange-haze","t":"space","q":"Why does Titan's sky look thick, orange and hazy instead of clear?"},{"id":"titan-slow-rain","t":"space","q":"Why would methane rain on Titan fall slowly enough that you could almost dodge it?"},{"id":"titan-thick-atmosphere","t":"space","q":"Why does tiny Titan have a thicker atmosphere than Mars, a whole planet?"},{"id":"toothpaste-swallow-no-sink","t":"space","q":"Why do some astronauts swallow their toothpaste instead of spitting it out?"},{"id":"triton-backwards-orbit","t":"space","q":"Why does Neptune's largest moon Triton orbit backwards compared to every other big moon?"},{"id":"triton-captured-not-born","t":"space","q":"Why do scientists think Triton used to be a completely different kind of object?"},{"id":"triton-doomed-rings","t":"space","q":"Why is Triton slowly falling towards Neptune instead of staying at a steady distance?"},{"id":"triton-nitrogen-geysers","t":"space","q":"Why does frozen Triton shoot geysers of gas despite being one of the coldest places measured?"},{"id":"tunguska-airburst","t":"space","q":"Why did a giant explosion flatten a Siberian forest in 1908 without leaving a crater?"},{"id":"underwater-training-buoyancy","t":"space","q":"Why do astronauts train for spacewalks in a giant swimming pool?"},{"id":"universe-age-measurement","t":"space","q":"Why do scientists say the universe is 13.8 billion years old?"},{"id":"universe-cooled-for-atoms","t":"space","q":"Why did the universe have to cool down before atoms could even form?"},{"id":"universe-finite-or-infinite","t":"space","q":"Why don't scientists know if the whole universe goes on forever?"},{"id":"universe-flat-geometry","t":"space","q":"Why do astronomers say the universe is flat rather than curved?"},{"id":"universe-hydrogen-helium","t":"space","q":"Why is the universe made mostly of hydrogen and helium?"},{"id":"universe-mass-energy-census","t":"space","q":"Why do scientists say the stuff we can touch is only a small slice of the universe?"},{"id":"universe-no-outside","t":"space","q":"Why is there no outside for the universe to expand into?"},{"id":"universe-same-age-everywhere","t":"space","q":"Why do we say the whole universe is the same age, even the far side we can't see?"},{"id":"universe-still-expanding","t":"space","q":"Why is the universe still getting bigger right now?"},{"id":"up-down-confusing-modules","t":"space","q":"Why can astronauts feel briefly lost about which way is up inside the space station?"},{"id":"uranus-diamond-rain","t":"space","q":"Why might it rain diamonds deep inside Uranus and Neptune?"},{"id":"uranus-greek-name","t":"space","q":"Why is Uranus the only planet named after a Greek god instead of a Roman one?"},{"id":"uranus-magnetic-field-lopsided","t":"space","q":"Why is Uranus's magnetic field so lopsided and off-centre?"},{"id":"uranus-methane-clouds","t":"space","q":"Why do bright cloud storms occasionally flare up on an otherwise featureless Uranus?"},{"id":"uranus-methane-colour","t":"space","q":"Why is Uranus a flat, pale cyan colour with almost no visible weather?"},{"id":"uranus-moons-shakespeare-names","t":"space","q":"Why are Uranus's moons named after Shakespeare characters instead of ancient myths?"},{"id":"uranus-moons-tilted-orbits","t":"space","q":"Why do Uranus's moons orbit up and down instead of side to side like most others?"},{"id":"uranus-retrograde-spin-technicality","t":"space","q":"Why do astronomers say Uranus spins backwards, even though it just looks tipped over?"},{"id":"uranus-rings-dark-narrow","t":"space","q":"Why are Uranus's rings dark and narrow instead of bright and wide like Saturn's?"},{"id":"uranus-rings-starlight-discovery","t":"space","q":"Why were Uranus's rings discovered by a star blinking, not by a photograph?"},{"id":"uranus-tilt","t":"space","q":"Why is Uranus lying on its side?"},{"id":"vacuum-exposure-blood-boil-myth","t":"space","q":"Why doesn't an astronaut's blood instantly boil if a spacesuit tears in space?"},{"id":"vehicle-assembly-building","t":"space","q":"Why are big rockets built standing straight up inside giant buildings instead of lying on their sides?"},{"id":"venus-backwards-spin","t":"space","q":"Why does Venus spin backwards compared to almost every other planet?"},{"id":"venus-coronae","t":"space","q":"Why does Venus have giant ring-shaped features found on no other planet?"},{"id":"venus-crush-pressure","t":"space","q":"Why would standing on Venus crush you almost instantly?"},{"id":"venus-hot","t":"space","q":"Why is Venus hotter than Mercury?"},{"id":"venus-lander-survival","t":"space","q":"Why did the first spacecraft to land on Venus only survive for minutes?"},{"id":"venus-radar-map","t":"space","q":"Why did scientists need radar, not photographs, to map Venus's surface?"},{"id":"venus-runaway-greenhouse","t":"space","q":"Why did Venus turn into a furnace when it might once have had oceans?"},{"id":"venus-slow-day","t":"space","q":"Why is one day on Venus longer than one Venus year?"},{"id":"venus-tallest-mountain","t":"space","q":"Why does Venus have a mountain taller than Mount Everest?"},{"id":"venus-volcano-count","t":"space","q":"Why does Venus have more volcanoes than anywhere else in the solar system?"},{"id":"venus-young-surface","t":"space","q":"Why does Venus have so few old, battered craters?"},{"id":"vesta-layered","t":"space","q":"Why does the asteroid Vesta have layers like a tiny planet?"},{"id":"viking-face-on-mars","t":"space","q":"Why did a 1976 photo convince some people a giant carved face was staring up from Mars?"},{"id":"viking-mars-life-test","t":"space","q":"Why did the first search for life on Mars end in a result scientists still argue about?"},{"id":"vomit-comet-parabolic-training","t":"space","q":"Why do astronauts train for weightlessness aboard a plane nicknamed the vomit comet?"},{"id":"voyager-golden-record","t":"space","q":"Why did the Voyager probes carry a golden record into deep space?"},{"id":"voyager-heliosphere","t":"space","q":"Why did Voyager 1 take over 35 years to leave the Sun's bubble?"},{"id":"voyager-instruments-shutting-down","t":"space","q":"Why is NASA switching off parts of the Voyager probes instead of leaving everything running?"},{"id":"water-recycling-iss","t":"space","q":"Why do astronauts drink water that used to be their own sweat and urine?"},{"id":"white-dwarf-carbon-oxygen","t":"space","q":"Why do the cores of most dead stars end up made of carbon and oxygen, and not something else?"},{"id":"white-dwarf-cooling-forever","t":"space","q":"Why will white dwarfs still be cooling long after the universe's current age runs out?"},{"id":"white-dwarf-density","t":"space","q":"Why can a teaspoon of white dwarf material weigh as much as a small truck?"},{"id":"white-dwarf-diamond","t":"space","q":"Why might some old white dwarf stars be giant crystallised diamonds?"},{"id":"white-dwarf-electron-support","t":"space","q":"Why doesn't a white dwarf keep collapsing under its own gravity?"},{"id":"wound-care-space-infection-risk","t":"space","q":"Why do doctors treat even a small cut extremely seriously in space?"},{"id":"zodiacal-light","t":"space","q":"Why does a faint cone of light appear after sunset that has nothing to do with any comet's tail?"},{"id":"zone-of-avoidance","t":"space","q":"Why is there a whole stripe of sky where almost no galaxies can be seen?"},{"id":"achilles-tendon","t":"body","q":"Why is the tendon at the back of your ankle named after a Greek hero's one weakness?"},{"id":"acoustic-reflex","t":"body","q":"Why does a sudden loud noise make tiny muscles deep in your ear clench up automatically?"},{"id":"addiction-hijack","t":"body","q":"Why can some substances make the brain crave them even when a person knows the harm?"},{"id":"altitude-breathless","t":"body","q":"Why do you feel breathless on a high mountain, even though the air is still about twenty-one percent oxygen?"},{"id":"altitude-red-cells","t":"body","q":"Why does your body make extra red blood cells high in the mountains?"},{"id":"alveoli-thin","t":"body","q":"Why are the walls of your smallest air sacs only one cell thick?"},{"id":"amygdala-fear","t":"body","q":"Why do you flinch at a loud bang before you've even worked out what caused it?"},{"id":"apple-crunch-loud-self","t":"body","q":"Why does crunching on an apple sound so much louder to you than to someone sitting right beside you?"},{"id":"arnold-reflex-cough","t":"body","q":"Why does touching deep inside your ear canal sometimes make you cough, even though your ear and your throat seem completely unrelated?"},{"id":"asthma-exhale-harder","t":"body","q":"Why does asthma make breathing out feel harder than breathing in?"},{"id":"astro-bone-loss","t":"body","q":"Why do astronauts' bones grow weaker after months in space?"},{"id":"astro-exercise","t":"body","q":"Why do astronauts have to exercise for hours every single day in space?"},{"id":"athlete-heart-rate","t":"body","q":"Why do trained athletes often have a slower resting heart rate?"},{"id":"baby-bones-300","t":"body","q":"Why are babies born with almost 100 more bones than grown-ups have?"},{"id":"baby-breath-rate","t":"body","q":"Why do babies breathe so much faster than grown-ups do?"},{"id":"baby-cartilage","t":"body","q":"Why is a lot of a baby's skeleton made of cartilage, not hard bone?"},{"id":"baby-ear-pressure-cry","t":"body","q":"Why do babies often cry more than adults when a plane takes off or lands?"},{"id":"baby-heart-rate","t":"body","q":"Why does a newborn baby's heart beat so much faster than yours?"},{"id":"baby-sweet-preference","t":"body","q":"Why do newborn babies pull a face at something bitter before they've ever eaten a single meal?"},{"id":"baby-teeth-matter","t":"body","q":"Why do baby teeth need proper care if they're only going to fall out anyway?"},{"id":"baby-tongue-thrust","t":"body","q":"Why do very young babies push solid food straight back out with their tongue instead of swallowing it?"},{"id":"baby-tooth-order-loss","t":"body","q":"Why do you usually lose your baby teeth in roughly the same order they first arrived?"},{"id":"balance-eyes-shut","t":"body","q":"Why is it so much harder to balance on one leg with your eyes closed?"},{"id":"balance-underwater-updown","t":"body","q":"Why can it be hard to tell which way is up when you're deep underwater?"},{"id":"baldness-genes","t":"body","q":"Why does baldness often run in families?"},{"id":"baldness-pattern","t":"body","q":"Why do some people go bald in a pattern instead of all over?"},{"id":"baldness-women","t":"body","q":"Why does hair loss usually look different in women than in men?"},{"id":"belly-breathing","t":"body","q":"Why does breathing 'from your belly' get more air in than breathing with just your chest?"},{"id":"belly-button","t":"body","q":"Why do I have a belly button?"},{"id":"bicep-tricep-swap","t":"body","q":"Why does your bicep bulge while your tricep goes slack at the very same moment?"},{"id":"birthmark-why","t":"body","q":"Why do some babies have birthmarks?"},{"id":"bite-force-masseter","t":"body","q":"Why is the muscle that closes your jaw considered one of the strongest in your whole body for its size?"},{"id":"bitter-receptor-count","t":"body","q":"Why does your tongue carry so many more kinds of bitter receptors than sweet or salty ones?"},{"id":"blind-spot","t":"body","q":"Why doesn't a blank patch of missing vision in each eye ever bother you?"},{"id":"blink","t":"body","q":"Why do we blink?"},{"id":"blister-clear-fluid","t":"body","q":"Why shouldn't you pop a blister?"},{"id":"blister-new-shoes","t":"body","q":"Why do new shoes give you blisters?"},{"id":"blood-blue","t":"body","q":"Why do veins look blue if blood is red?"},{"id":"blood-donation","t":"body","q":"Why can you safely give away a cup of blood and be fine in days?"},{"id":"blood-stays-liquid","t":"body","q":"Why doesn't blood turn solid while it's still flowing around inside you?"},{"id":"blood-taste-metal","t":"body","q":"Why does blood taste metallic if you cut your lip?"},{"id":"blood-test","t":"body","q":"Why can a doctor learn so much from just a few drops of your blood?"},{"id":"blood-types","t":"body","q":"Why do people have different blood types like A, B and O?"},{"id":"blood-vessel-muscle","t":"body","q":"Why do the tubes carrying your blood have muscle built into their walls?"},{"id":"blood-warmth","t":"body","q":"Why is blood warm instead of room temperature?"},{"id":"blow-cool-warm-breath","t":"body","q":"Why does blowing on hot soup cool it down, while blowing on cold hands warms them up?"},{"id":"blue-lips-oxygen","t":"body","q":"Why can lips or fingertips look faintly blue when someone is very short of oxygen?"},{"id":"blush","t":"body","q":"Why do we blush?"},{"id":"boat-land-sickness","t":"body","q":"Why can you still feel like you're swaying for a while after stepping off a boat onto solid ground?"},{"id":"body-hair-fine","t":"body","q":"Why is the hair on your arms and legs so much finer than the hair on your head?"},{"id":"body-hair-purpose","t":"body","q":"Why do we still have body hair if it doesn't keep us warm any more?"},{"id":"bone-alive","t":"body","q":"Why is a bone inside your body actually alive, not like a dry stick?"},{"id":"bone-callus","t":"body","q":"Why does a healing broken bone form a lump before it becomes smooth again?"},{"id":"bone-conduction-voice","t":"body","q":"Why does your own recorded voice sound so different from the voice you hear when you talk?"},{"id":"bone-hollow","t":"body","q":"Why are your bones hollow in the middle instead of solid all the way through?"},{"id":"bone-remodel","t":"body","q":"Why does your skeleton quietly rebuild itself, even when nothing is broken?"},{"id":"bone-vinegar","t":"body","q":"Why does soaking a chicken bone in vinegar turn it rubbery?"},{"id":"bones-strong","t":"body","q":"Why are bones so strong?"},{"id":"booger-formation","t":"body","q":"Why do boogers form inside your nose?"},{"id":"bp-two-numbers","t":"body","q":"Why does blood pressure get written as two numbers, not one?"},{"id":"bppv-crystals","t":"body","q":"Why can rolling over in bed suddenly make the room feel like it's spinning?"},{"id":"braces-move-teeth","t":"body","q":"Why can braces actually move a tooth through solid bone?"},{"id":"braille-reading","t":"body","q":"Why can a blind person read whole sentences just with their fingertips?"},{"id":"brain-energy-use","t":"body","q":"Why does your brain use so much energy for something that barely weighs a kilogram?"},{"id":"brain-freeze","t":"body","q":"Why does ice cream give you a headache?"},{"id":"brain-grey-white","t":"body","q":"Why does the brain have both grey and white parts inside it?"},{"id":"brain-halves","t":"body","q":"Why are the two halves of your brain joined by a thick cable of nerves?"},{"id":"brain-plasticity","t":"body","q":"Why can the brain sometimes take over lost functions after an injury?"},{"id":"brain-size-intelligence-myth","t":"body","q":"Why doesn't having a bigger brain make an animal, or a person, smarter?"},{"id":"brain-wrinkles","t":"body","q":"Why is the brain covered in wrinkles and folds?"},{"id":"brainstem-pacemaker","t":"body","q":"Why does breathing keep going even when someone is completely unconscious?"},{"id":"breakpoint-carotid-body","t":"body","q":"Why is there a moment holding your breath where you simply can't hold on any longer, no matter how hard you try?"},{"id":"breath-see-cold","t":"body","q":"Why can you sometimes see your own breath in the air?"},{"id":"breathing-feedforward","t":"body","q":"Why does your breathing speed up the instant you start exercising, before your muscles even ask for more air?"},{"id":"broken-nose-bruise-easy","t":"body","q":"Why does even a fairly light knock to the nose cause bleeding and bruising so easily?"},{"id":"bruise-extra-tender","t":"body","q":"Why does even a gentle poke hurt more on a bruise than on normal skin?"},{"id":"bruises","t":"body","q":"Why do bruises change colour?"},{"id":"brushing-twice-day","t":"body","q":"Why do dentists say to brush twice a day rather than just once?"},{"id":"calcium-bank","t":"body","q":"Why does your body raid your own bones for calcium if your food runs short?"},{"id":"callus-forms","t":"body","q":"Why do calluses form on hands that grip things a lot?"},{"id":"callus-no-pain","t":"body","q":"Why don't calluses hurt even though the skin is thick and tough?"},{"id":"canker-sore-formation","t":"body","q":"Why do small painful mouth ulcers sometimes appear for no obvious reason?"},{"id":"capillary-queue","t":"body","q":"Why do red blood cells have to queue up single file in tiny vessels?"},{"id":"capillary-thinness","t":"body","q":"Why do your smallest blood vessels have to be so incredibly thin?"},{"id":"carbon-monoxide-no-smell","t":"body","q":"Why can't your nose warn you about dangerous gases like carbon monoxide?"},{"id":"cartilage-cushion","t":"body","q":"Why doesn't the end of a bone wear away, even after a lifetime of moving?"},{"id":"cartilage-slow-heal","t":"body","q":"Why does hurt knee cartilage take so much longer to heal than a cut on skin?"},{"id":"cast-heal","t":"body","q":"Why does a broken bone need to be kept completely still to heal straight?"},{"id":"cavity-bacteria-acid","t":"body","q":"Why doesn't sugar actually eat a hole through your teeth?"},{"id":"cavity-spreads","t":"body","q":"Why does a small cavity keep getting bigger instead of stopping on its own?"},{"id":"cerebellum-balance","t":"body","q":"Why does a fist-sized lump at the back of your brain matter so much for staying upright?"},{"id":"chewing-gum-help","t":"body","q":"Why can chewing sugar-free gum after a meal actually help your teeth?"},{"id":"chilli-burn","t":"body","q":"Why does chilli feel like it's burning your mouth when nothing is actually hot?"},{"id":"chipped-tooth-delay","t":"body","q":"Why might a chipped tooth not hurt at all until later?"},{"id":"circadian-clock-brain","t":"body","q":"Why does a speck of brain smaller than a grain of rice control your whole daily rhythm?"},{"id":"citrus-enamel-erosion","t":"body","q":"Why can eating a lot of citrus fruit wear your enamel thin?"},{"id":"clothes-fade-feel","t":"body","q":"Why do you stop feeling your clothes touching your skin after a while?"},{"id":"co2-bicarbonate","t":"body","q":"Why doesn't the carbon dioxide in your blood just dissolve like fizz in a soft drink?"},{"id":"cochlea-snail-shape","t":"body","q":"Why is the inner ear coiled up like a snail shell?"},{"id":"cocktail-party-effect","t":"body","q":"Why can you suddenly hear your own name spoken clearly across a noisy, crowded room?"},{"id":"cold-air-cough","t":"body","q":"Why does breathing in very cold air sometimes make your chest feel tight or make you cough?"},{"id":"cold-air-smell-less","t":"body","q":"Why is it harder to smell much on a freezing cold day outside?"},{"id":"cold-fingers-clumsy","t":"body","q":"Why do your fingers get clumsy in the cold before they even start to hurt?"},{"id":"cold-food-taste-less-sweet","t":"body","q":"Why does the exact same ice cream taste less sweet once it's melted and warmed up a little?"},{"id":"colds","t":"body","q":"Why do I get a cold?"},{"id":"color-brain-invention","t":"body","q":"Why is colour something your brain invents, not something light actually has?"},{"id":"concert-earplugs","t":"body","q":"Why do musicians wear special earplugs instead of just stuffing their ears with cotton wool?"},{"id":"concussion","t":"body","q":"Why can a knock to the head cause problems even with no cut or bruise at all?"},{"id":"coronary-arteries","t":"body","q":"Why does your heart need its own private blood vessels to feed itself?"},{"id":"cough-reflex","t":"body","q":"Why does a tickle deep in your throat make you cough without any warning?"},{"id":"critical-period-language","t":"body","q":"Why do young children pick up a new language so much faster than adults?"},{"id":"crooked-teeth-crowding","t":"body","q":"Why do teeth sometimes come in crooked instead of straight?"},{"id":"crossed-wiring","t":"body","q":"Why does the left side of your brain control the right side of your body?"},{"id":"cry","t":"body","q":"Why do we cry?"},{"id":"dead-skin-dust","t":"body","q":"Why is a lot of household dust actually dead skin?"},{"id":"decibel-scale","t":"body","q":"Why can a sound that doesn't feel twice as loud actually carry ten times more energy?"},{"id":"deep-pressure-calm","t":"body","q":"Why can a firm hug or a heavy blanket feel calming?"},{"id":"deja-vu","t":"body","q":"Why do you sometimes feel you've lived through a brand new moment before?"},{"id":"dentist-mirror-pick","t":"body","q":"Why does a dentist poke around your teeth with a small metal pick?"},{"id":"dentist-numb","t":"body","q":"Why does a dentist's injection stop you feeling the drill?"},{"id":"deviated-septum","t":"body","q":"Why can breathing feel noticeably easier through one nostril than the other, all the time, not just some hours?"},{"id":"diaphragm-exception","t":"body","q":"Why does the muscle you breathe with break the usual rule about which muscles you control?"},{"id":"dizzy-spin","t":"body","q":"Why do I get dizzy when I spin?"},{"id":"dizzy-standing","t":"body","q":"Why do you sometimes see stars if you stand up too quickly?"},{"id":"dog-nose-compare","t":"body","q":"Why can dogs still out-smell humans at tracking a trail, even though our noses aren't as weak as people think?"},{"id":"dog-panting","t":"body","q":"Why do dogs pant to cool down instead of breathing normally like we do to stay cool?"},{"id":"dopamine-reward","t":"body","q":"Why does finishing a level in a game or scoring a goal feel so satisfying?"},{"id":"double-circulation","t":"body","q":"Why does your blood pass through your lungs before anywhere else?"},{"id":"dreams","t":"body","q":"Why do we dream?"},{"id":"drool-during-sleep","t":"body","q":"Why do some people wake up with a small wet patch on the pillow from drooling in their sleep?"},{"id":"dry-mouth-fear","t":"body","q":"Why does your mouth suddenly go dry right before you have to speak in front of a crowd?"},{"id":"ear-canal-length","t":"body","q":"Why does the narrow tunnel leading into your ear matter so much for hearing?"},{"id":"ear-cold-fast","t":"body","q":"Why do your ears often feel colder than the rest of your face on a chilly day?"},{"id":"ear-infection-kids","t":"body","q":"Why do young children get ear infections far more often than most adults do?"},{"id":"ear-pop-plane","t":"body","q":"Why do your ears pop when a plane takes off or a lift climbs a tall building fast?"},{"id":"ear-shape-funnel","t":"body","q":"Why do your outer ears have all those ridges and curves instead of being flat?"},{"id":"ear-shape-unique","t":"body","q":"Why is the shape of everyone's outer ear a little different, almost like a fingerprint?"},{"id":"ear-wiggling-muscle","t":"body","q":"Why can some people wiggle their ears on command while most people can't move theirs at all?"},{"id":"earache-referred-pain","t":"body","q":"Why can a sore throat or an aching tooth sometimes make your ear hurt too?"},{"id":"earbud-volume-limit","t":"body","q":"Why do some phones warn you or automatically limit the volume when you turn music up too high?"},{"id":"eardrum-thin","t":"body","q":"Why is your eardrum thinner than a sheet of paper?"},{"id":"early-strength-nerves","t":"body","q":"Why do your muscles get noticeably stronger in the first weeks of training, before they've grown at all?"},{"id":"earwax-cotton-bud-danger","t":"body","q":"Why do doctors say not to use cotton buds to clean earwax out?"},{"id":"earwax-migrate","t":"body","q":"Why does earwax move out of your ear on its own without you doing anything?"},{"id":"earwax-purpose","t":"body","q":"Why does your body bother making earwax at all?"},{"id":"enamel-crystal-structure","t":"body","q":"Why can enamel be harder than anything else your body makes, but only ever made once?"},{"id":"epiglottis-flap","t":"body","q":"Why doesn't food fall straight into your windpipe when you swallow?"},{"id":"eustachian-tube-yawn","t":"body","q":"Why does yawning or swallowing help unclog ears that feel blocked or full?"},{"id":"everest-bottled-oxygen","t":"body","q":"Why do climbers near the top of Mount Everest breathe from bottles instead of just the air around them?"},{"id":"exercise-builds-muscle","t":"body","q":"Why does lifting something heavy again and again make a muscle bigger?"},{"id":"exercise-deeper-breaths","t":"body","q":"Why does hard exercise make you breathe deeper as well as faster, not just faster?"},{"id":"exercise-stitch","t":"body","q":"Why do you get a sharp stitch in your side when you run?"},{"id":"exhaled-oxygen-myth","t":"body","q":"Why does mouth-to-mouth rescue breathing actually work, if you've already used the air?"},{"id":"explosion-instant-damage","t":"body","q":"Why can a single very loud bang, like a firework going off close by, damage hearing instantly in a way ordinary loud noise usually doesn't?"},{"id":"eye-accommodation-tired","t":"body","q":"Why does staring at something close up for a long time tire your eyes out?"},{"id":"eye-afterimage","t":"body","q":"Why does staring at one colour then looking away show you the opposite colour?"},{"id":"eye-animal-eyeshine","t":"body","q":"Why do some animals' eyes glow in torchlight, but human eyes never do?"},{"id":"eye-baby-blurry-vision","t":"body","q":"Why can newborn babies barely see further than their own parent's face?"},{"id":"eye-baby-colour","t":"body","q":"Why do some babies' eyes change colour after they're born?"},{"id":"eye-chart-acuity","t":"body","q":"Why does an eye chart get harder to read the further down it goes?"},{"id":"eye-chlorine-red","t":"body","q":"Why does swimming in a pool leave your eyes red and stinging?"},{"id":"eye-colour-blind","t":"body","q":"Why can't some people tell red and green apart?"},{"id":"eye-colour-blind-boys","t":"body","q":"Why is colour blindness so much more common in boys than girls?"},{"id":"eye-colour-genes","t":"body","q":"Why isn't eye colour decided by just one simple gene?"},{"id":"eye-colour-light-shift","t":"body","q":"Why can the same person's eyes look a different colour in different light?"},{"id":"eye-converge-nose","t":"body","q":"Why do your eyes cross a little when you look at something right in front of your nose?"},{"id":"eye-crying-runny-nose","t":"body","q":"Why does crying so often give you a runny nose too?"},{"id":"eye-dark-adapt","t":"body","q":"Why do your eyes take minutes to adjust when the lights go out?"},{"id":"eye-dark-colour","t":"body","q":"Why can't you see colours well in near darkness?"},{"id":"eye-dim-light-myth","t":"body","q":"Why doesn't reading in dim light really damage your eyesight?"},{"id":"eye-eyeball-sphere","t":"body","q":"Why is your eyeball almost a perfect sphere?"},{"id":"eye-floaters","t":"body","q":"Why do tiny specks sometimes drift across your vision when you look at a blank sky?"},{"id":"eye-fovea","t":"body","q":"Why is there one tiny spot in your eye where vision is sharpest?"},{"id":"eye-glasses-bend-light","t":"body","q":"Why can a curved piece of glass fix blurry eyesight?"},{"id":"eye-lazy-eye-patch","t":"body","q":"Why do doctors sometimes cover a child's stronger eye with a patch?"},{"id":"eye-move-together","t":"body","q":"Why do your two eyes almost always move together instead of separately?"},{"id":"eye-myopia-hyperopia","t":"body","q":"Why do some people need glasses to see far away, and others to see up close?"},{"id":"eye-onion-sting","t":"body","q":"Why do onions make your eyes sting and water?"},{"id":"eye-open-close-muscles","t":"body","q":"Why does blinking need one muscle to shut your eye and a different one to open it?"},{"id":"eye-peripheral-vision","t":"body","q":"Why is the edge of what you see blurrier and less colourful than the middle?"},{"id":"eye-photic-sneeze","t":"body","q":"Why does stepping into bright sunlight make some people sneeze?"},{"id":"eye-presbyopia","t":"body","q":"Why do many people suddenly need reading glasses in their forties, even with perfect vision before?"},{"id":"eye-pupil-hole","t":"body","q":"Why is your pupil actually a hole, not a black dot?"},{"id":"eye-reading-saccades","t":"body","q":"Why do your eyes jump instead of gliding smoothly across a page while you read?"},{"id":"eye-red-eye-photos","t":"body","q":"Why do human eyes sometimes glow red in flash photographs?"},{"id":"eye-retina-upside-down","t":"body","q":"Why is the image on the back of your eye actually upside down?"},{"id":"eye-rods-cones-count","t":"body","q":"Why does your eye have two totally different kinds of light-sensing cells?"},{"id":"eye-saccadic-suppression","t":"body","q":"Why can't you ever actually see your own eyes moving in a mirror?"},{"id":"eye-sclera-white","t":"body","q":"Why does the white of your eye have its own special name?"},{"id":"eye-screen-dry","t":"body","q":"Why do your eyes feel dry after staring at a screen for a long time?"},{"id":"eye-six-muscles","t":"body","q":"Why does each eye need six separate muscles just to look around?"},{"id":"eye-sleep-rheum","t":"body","q":"Why do you get 'sleep' in the corners of your eyes overnight?"},{"id":"eye-strabismus-squint","t":"body","q":"Why does one eye sometimes point in a slightly different direction from the other?"},{"id":"eye-stye","t":"body","q":"Why does a stye form on your eyelid?"},{"id":"eye-tear-film-layers","t":"body","q":"Why is the thin layer of tears over your eye actually three layers, not one?"},{"id":"eye-tv-close-myth","t":"body","q":"Why doesn't sitting close to the television ruin your eyesight?"},{"id":"eye-uv-infrared","t":"body","q":"Why can't you see ultraviolet or infrared light, even though it's really there?"},{"id":"eye-vitamin-a-blindness","t":"body","q":"Why does too little vitamin A make it hard to see at night?"},{"id":"eye-yawn-water","t":"body","q":"Why do your eyes water when you yawn?"},{"id":"eyebrows","t":"body","q":"Why do we have eyebrows?"},{"id":"eyelashes-blink","t":"body","q":"Why do eyelashes make you blink before something even touches your eye?"},{"id":"eyelashes-length","t":"body","q":"Why do eyelashes stop growing at just the right length?"},{"id":"eyelid-twitch","t":"body","q":"Why does your eyelid sometimes twitch on its own for no reason?"},{"id":"face-muscle-skin","t":"body","q":"Why do the muscles in your face attach to skin instead of only to bone?"},{"id":"fainting-blood","t":"body","q":"Why do some people faint at the sight of blood?"},{"id":"fat-lip-illusion","t":"body","q":"Why does your lip feel huge after a numbing injection, even though it isn't?"},{"id":"feel-fly-land","t":"body","q":"Why can you feel a fly land on your arm before you even see it?"},{"id":"feet-smell","t":"body","q":"Why do feet smell?"},{"id":"femur-longest","t":"body","q":"Why is the bone in your thigh the longest bone in your body?"},{"id":"fetal-blood-shortcut","t":"body","q":"Why does a baby before birth have shortcuts in its blood flow?"},{"id":"fetal-heart-early","t":"body","q":"Why does a baby's heart start beating before its brain has formed?"},{"id":"fetal-lungs-fluid","t":"body","q":"Why are a baby's lungs full of fluid before it's even born?"},{"id":"fight-or-flight-brain","t":"body","q":"Why does your whole body suddenly change the instant your brain senses danger?"},{"id":"filling-needed","t":"body","q":"Why does a cavity need a filling instead of just healing over time?"},{"id":"fingerprint-ridges-feel","t":"body","q":"Why do the ridges on your fingertips help you feel texture better?"},{"id":"fingerprints","t":"body","q":"Why do we have fingerprints?"},{"id":"flashbulb-memory","t":"body","q":"Why do strong emotions burn some memories in so vividly while ordinary days blur together?"},{"id":"flavour-before-birth","t":"body","q":"Why might a baby already have flavour preferences before ever eating solid food?"},{"id":"flavour-vs-smell","t":"body","q":"Why does food taste so bland when your nose is completely blocked?"},{"id":"floating-ribs","t":"body","q":"Why don't your bottom two ribs reach all the way around to your breastbone?"},{"id":"floss-between-teeth","t":"body","q":"Why can't brushing alone keep your teeth properly clean?"},{"id":"fluoride-remineralize","t":"body","q":"Why does fluoride in toothpaste actually help stop cavities?"},{"id":"fontanelle","t":"body","q":"Why can you feel a soft, pulsing gap on top of a newborn baby's head?"},{"id":"food-poo","t":"body","q":"Why does food turn into poo?"},{"id":"freckles-fade-winter","t":"body","q":"Why do some people's freckles fade in winter and come back in summer?"},{"id":"freckles-not-everyone","t":"body","q":"Why do only some people get freckles?"},{"id":"freediver-training","t":"body","q":"Why can trained free-divers hold their breath for several minutes when most people manage barely one?"},{"id":"freediving-blackout","t":"body","q":"Why can breath-holding underwater sometimes go wrong without any warning at all?"},{"id":"fridge-hum-notice","t":"body","q":"Why do you suddenly notice a fridge humming the moment the room goes quiet?"},{"id":"funny-bone-nerve","t":"body","q":"Why does bumping your elbow send a tingle shooting down to your fingers?"},{"id":"funny-bone-pun","t":"body","q":"Why is the ticklish nerve at your elbow nicknamed the 'funny bone'?"},{"id":"gap-teeth-diastema","t":"body","q":"Why do some children have a natural gap between their front teeth?"},{"id":"gasp-startle","t":"body","q":"Why do you suck in a sudden sharp gasp when you're startled or plunge into cold water?"},{"id":"goosebumps","t":"body","q":"Why do we get goosebumps?"},{"id":"greenstick-break","t":"body","q":"Why can a young child's arm bend and crack instead of snapping clean in two?"},{"id":"growth-plate","t":"body","q":"Why do kids have a soft stripe near the end of each bone that adults don't?"},{"id":"growth-plate-break","t":"body","q":"Why can a broken bone near a growth plate worry doctors more than other breaks?"},{"id":"growth-stop","t":"body","q":"Why do you eventually stop growing taller, no matter how much you eat?"},{"id":"gum-swallow-myth","t":"body","q":"Why doesn't swallowed gum really sit in your stomach for seven years?"},{"id":"gut-brain-axis","t":"body","q":"Why does your gut send more signals up to your brain than your brain sends down?"},{"id":"gut-second-brain","t":"body","q":"Why does your gut have its own network of nerves, almost like a second brain?"},{"id":"habit-basal-ganglia","t":"body","q":"Why do habits eventually feel like they happen without you thinking at all?"},{"id":"hair-alive-or-dead","t":"body","q":"Why is the hair on your head actually dead?"},{"id":"hair-arms-length","t":"body","q":"Why doesn't the hair on your arms ever need a haircut?"},{"id":"hair-cells-no-regrow","t":"body","q":"Why can't damaged hair cells inside your ear grow back the way a cut on your skin heals?"},{"id":"hair-cells-sound","t":"body","q":"Why do tiny hairs inside your ear matter for hearing anything at all?"},{"id":"hair-colour","t":"body","q":"Why is everyone's hair a different colour?"},{"id":"hair-curl-shrink","t":"body","q":"Why does curly hair look shorter than it really is?"},{"id":"hair-curly-straight","t":"body","q":"Why is some people's hair curly and other people's straight?"},{"id":"hair-fall-daily","t":"body","q":"Why does hair fall out of your head every single day?"},{"id":"hair-follicle-count","t":"body","q":"Why do you have millions of hairs on your skin you can't even see?"},{"id":"hair-frizz","t":"body","q":"Why does hair frizz up on a humid day?"},{"id":"hair-grey","t":"body","q":"Why does hair turn grey or white as people get older?"},{"id":"hair-grows","t":"body","q":"Why does hair keep growing?"},{"id":"hair-keratin-same","t":"body","q":"Why are hair and nails made of the same stuff?"},{"id":"hair-not-overnight","t":"body","q":"Why can't hair really turn white overnight from a fright?"},{"id":"hair-red-rare","t":"body","q":"Why is red hair the rarest natural hair colour?"},{"id":"hair-scales","t":"body","q":"Why does hair feel smoother running one way than the other?"},{"id":"hair-springs-back","t":"body","q":"Why does straightened hair curl back up after a swim?"},{"id":"hair-stress-fall","t":"body","q":"Why can a big shock or illness make hair fall out weeks later?"},{"id":"hair-strong","t":"body","q":"Why is a single strand of hair so hard to snap?"},{"id":"hair-thick-areas","t":"body","q":"Why does hair grow thick in some places and stay wispy in others?"},{"id":"hair-wet-dark","t":"body","q":"Why does hair look darker when it's wet?"},{"id":"haircuts-no-pain","t":"body","q":"Why doesn't it hurt to get a haircut?"},{"id":"handedness","t":"body","q":"Why are most people right-handed and only some left-handed?"},{"id":"head-hair-kept","t":"body","q":"Why did humans keep long hair on their heads but lose it almost everywhere else?"},{"id":"headache-origin","t":"body","q":"Why can your head hurt so badly when your brain itself can't feel pain?"},{"id":"hearing-range-kids-adults","t":"body","q":"Why can children hear high-pitched sounds that most adults have completely lost?"},{"id":"heart-attack-myth","t":"body","q":"Why does a heart attack happen if nothing hits your heart at all?"},{"id":"heart-av-delay","t":"body","q":"Why do your heart's top chambers squeeze just before the bottom ones?"},{"id":"heart-beats-myth","t":"body","q":"Why isn't it true that you're born with a fixed number of heartbeats?"},{"id":"heart-cant-flex","t":"body","q":"Why can't you flex your heart on purpose the way you flex your bicep?"},{"id":"heart-different-muscle","t":"body","q":"Why is the muscle in your heart a completely different type from the muscle in your arm?"},{"id":"heart-faster","t":"body","q":"Why does my heart beat faster when I run?"},{"id":"heart-fist-size","t":"body","q":"Why is your heart roughly the same size as your own fist?"},{"id":"heart-four-chambers","t":"body","q":"Why does your heart have four separate rooms instead of one big pump?"},{"id":"heart-left-thicker","t":"body","q":"Why is the left side of your heart's wall thicker than the right?"},{"id":"heart-lub-dub","t":"body","q":"Why does your heartbeat sound like lub-dub instead of one single thump?"},{"id":"heart-own-rhythm","t":"body","q":"Why does heart muscle keep its own beat, even without a signal from the brain?"},{"id":"heart-position-left","t":"body","q":"Why does your heart sit slightly left instead of dead centre?"},{"id":"heart-race-fear","t":"body","q":"Why does your heart start racing the instant you're scared?"},{"id":"heart-rate-lifespan","t":"body","q":"Why do big animals almost always have slower heartbeats than small ones?"},{"id":"heart-rest-between-beats","t":"body","q":"Why does your heart get to rest, even though it beats every second of your life?"},{"id":"heart-symbol-shape","t":"body","q":"Why doesn't the heart symbol on cards look anything like a real heart?"},{"id":"heart-transplant","t":"body","q":"Why can a transplanted heart start beating with no nerves attached?"},{"id":"heart-valve-backflow","t":"body","q":"Why doesn't blood in your heart ever slosh backward between beats?"},{"id":"hemophilia","t":"body","q":"Why can't a small cut stop bleeding properly for some people?"},{"id":"hiccups","t":"body","q":"Why do we get hiccups?"},{"id":"hip-knee-joints","t":"body","q":"Why can your hip twirl your leg in a circle but your knee only swings one way?"},{"id":"hippocampus-memory","t":"body","q":"Why can damage to one small part of the brain stop someone forming new memories?"},{"id":"holding-nose-medicine","t":"body","q":"Why does pinching your nose shut make bad-tasting medicine seem less awful?"},{"id":"humans-less-fur","t":"body","q":"Why do humans have so much less fur than other mammals?"},{"id":"humans-not-hairless","t":"body","q":"Why aren't humans actually 'hairless' at all?"},{"id":"hyperventilate-dizzy","t":"body","q":"Why can breathing too fast for too long make you feel dizzy and tingly?"},{"id":"ice-burn","t":"body","q":"Why can holding an ice cube too long start to feel like it's burning?"},{"id":"infantile-amnesia","t":"body","q":"Why can't you remember anything from when you were a baby?"},{"id":"iron-tiredness","t":"body","q":"Why can too little iron in your diet leave you feeling worn out?"},{"id":"itch","t":"body","q":"Why do we itch?"},{"id":"itch-scratch-cycle","t":"body","q":"Why does scratching an itch often make it itchier?"},{"id":"jaw-moves","t":"body","q":"Why is your jawbone the only bone in your skull that can move?"},{"id":"joint-slippery","t":"body","q":"Why do your joints move so smoothly, with almost no friction at all?"},{"id":"jump-unexpected-touch","t":"body","q":"Why do you jump when someone taps you unexpectedly from behind?"},{"id":"kids-heal-faster","t":"body","q":"Why do children's broken bones mend faster than an adult's broken bone?"},{"id":"knee-tap-reflex","t":"body","q":"Why does your leg kick out when a doctor taps just below your kneecap?"},{"id":"knuckle-myth","t":"body","q":"Why doesn't cracking your knuckles actually give you arthritis?"},{"id":"knuckle-pop","t":"body","q":"Why does cracking your knuckles make a sudden popping sound?"},{"id":"knuckle-reload","t":"body","q":"Why do your knuckles need to wait before they can crack again?"},{"id":"laughing-breathless","t":"body","q":"Why can laughing so hard actually leave you gasping for breath?"},{"id":"learning-styles-myth","t":"body","q":"Why is it a myth that some people learn best visually and others by listening?"},{"id":"left-right-brain-myth","t":"body","q":"Why isn't it true that some people are 'left-brained' and others 'right-brained'?"},{"id":"lice-itch","t":"body","q":"Why do lice make your scalp itch?"},{"id":"lice-nits-glue","t":"body","q":"Why do lice glue their eggs onto hair right next to the scalp?"},{"id":"lice-no-jump","t":"body","q":"Why can't head lice jump or fly to a new head?"},{"id":"lice-spread","t":"body","q":"Why do head lice spread so fast among kids at school?"},{"id":"look-like-parents","t":"body","q":"Why do I look like my parents?"},{"id":"loud-music-damage","t":"body","q":"Why can loud music through headphones cause hearing damage that never goes away?"},{"id":"lukewarm-water-confuse","t":"body","q":"Why can the same lukewarm water feel hot to one hand and cold to the other?"},{"id":"lung-lobes-uneven","t":"body","q":"Why does your right lung have three sections but your left one only has two?"},{"id":"lungs-branch-tree","t":"body","q":"Why do your lungs look like an upside-down tree inside?"},{"id":"lungs-no-muscle","t":"body","q":"Why can't your lungs suck air in by themselves?"},{"id":"marrow-blood","t":"body","q":"Why does the soft marrow inside your bones make your blood?"},{"id":"marrow-donate","t":"body","q":"Why can a stranger's bone marrow save the life of someone with leukaemia?"},{"id":"marrow-yellow","t":"body","q":"Why does the marrow inside your bones turn from red to yellow as you grow?"},{"id":"memory-forget","t":"body","q":"Why do we forget things?"},{"id":"memory-reconstruction","t":"body","q":"Why isn't a memory like a video recording of what really happened?"},{"id":"metallic-taste-causes","t":"body","q":"Why can a small cut inside your mouth, or even certain vitamins, leave a metallic taste behind?"},{"id":"milk-teeth-name","t":"body","q":"Why are baby teeth sometimes called milk teeth?"},{"id":"mint-cool","t":"body","q":"Why does mint make your mouth feel cool when nothing got colder?"},{"id":"molars-arrive-quietly","t":"body","q":"Why can a big back tooth arrive without you ever losing a baby tooth first?"},{"id":"moles-appear-later","t":"body","q":"Why do new moles appear on your skin as you get older?"},{"id":"moles-vs-freckles","t":"body","q":"Why are moles raised and dark while freckles are just flat colour?"},{"id":"motion-sickness-mismatch","t":"body","q":"Why does reading in a moving car make some people feel queasy within minutes?"},{"id":"motor-unit-size","t":"body","q":"Why can your eyes move with pinpoint precision but your thighs can't?"},{"id":"mouth-breathing-exercise","t":"body","q":"Why do you start breathing through your mouth once you're running hard?"},{"id":"mucus-color-myth","t":"body","q":"Why doesn't green or yellow snot always mean you need antibiotics?"},{"id":"mucus-escalator","t":"body","q":"Why don't the germs and dust in every breath build up inside your lungs?"},{"id":"multitasking-myth","t":"body","q":"Why can't your brain really do two thinking tasks at exactly the same time?"},{"id":"muscle-ache","t":"body","q":"Why do my legs ache the day after sport?"},{"id":"muscle-cramp","t":"body","q":"Why does a muscle suddenly lock into a painful cramp?"},{"id":"muscle-fatigue-shake","t":"body","q":"Why do your arms start shaking when you hold something heavy for too long?"},{"id":"muscle-limit-shorten","t":"body","q":"Why can't a flexed muscle scrunch up much shorter than about a third of its length?"},{"id":"muscle-only-pull","t":"body","q":"Why can a muscle only pull and never push?"},{"id":"muscle-pairs","t":"body","q":"Why do muscles almost always work in pairs?"},{"id":"muscle-shorten-fatten","t":"body","q":"Why does a muscle get shorter and fatter when it contracts?"},{"id":"museum-gaps","t":"body","q":"Why do the bones hanging in a museum skeleton not quite touch each other?"},{"id":"myelin-speed","t":"body","q":"Why do some nerve signals travel over a hundred times faster than others?"},{"id":"nail-no-feeling","t":"body","q":"Why can't you feel it when someone taps only your fingernail?"},{"id":"nails-biting-habit","t":"body","q":"Why is nail biting such a hard habit to stop?"},{"id":"nails-biting-hurt","t":"body","q":"Why does biting your nails hurt the skin but not the nail itself?"},{"id":"nails-fingers-faster","t":"body","q":"Why do fingernails grow faster than toenails?"},{"id":"nails-grow","t":"body","q":"Why do nails grow at all?"},{"id":"nails-hard","t":"body","q":"Why are nails hard but still able to bend?"},{"id":"nails-moon","t":"body","q":"Why does every nail have a little pale moon at the bottom?"},{"id":"nails-pink","t":"body","q":"Why do nails look pink if they're actually see-through?"},{"id":"nails-white-spots","t":"body","q":"Why do white spots show up on nails?"},{"id":"nasal-cycle","t":"body","q":"Why does one nostril often feel more blocked than the other, even when you're not sick?"},{"id":"nerve-heal-cut","t":"body","q":"Why can a cut nerve in your finger heal, when a cut spinal cord usually can't?"},{"id":"neurogenesis-myth","t":"body","q":"Why is it outdated to say the brain can never grow new cells?"},{"id":"neuron-shape","t":"body","q":"Why do brain cells look nothing like other cells in your body?"},{"id":"newborn-brain-unfinished","t":"body","q":"Why is a human baby's brain so unfinished compared with other newborn animals?"},{"id":"newborn-first-breath","t":"body","q":"Why does a newborn baby's very first breath take so much more effort than every breath after it?"},{"id":"newborn-smell-mother","t":"body","q":"Why can a newborn baby recognise its mother's smell within days of being born?"},{"id":"night-cramp","t":"body","q":"Why do cramps so often strike at night while you're lying still in bed?"},{"id":"noise-induced-gradual","t":"body","q":"Why can years of ordinary loud noise damage hearing even without one single memorable loud bang?"},{"id":"nose-bridge-bone-cartilage","t":"body","q":"Why is the top of your nose hard but the tip is soft and bendy?"},{"id":"nose-congestion-swelling","t":"body","q":"Why does a stuffy nose feel blocked even when it isn't dripping much?"},{"id":"nose-hair","t":"body","q":"Why do you have hairs growing just inside your nose?"},{"id":"nose-keeps-growing","t":"body","q":"Why does your nose seem to keep growing slowly your whole life, when most of your skeleton stops?"},{"id":"nose-picking-urge-dry","t":"body","q":"Why do you feel a stronger urge to clear your nose with a finger when the air is dry or dusty?"},{"id":"nose-septum-wall","t":"body","q":"Why is there a wall down the middle of your nose?"},{"id":"nose-shape-climate","t":"body","q":"Why do people's noses come in such different shapes and sizes?"},{"id":"nose-turbinates","t":"body","q":"Why does the inside of your nose feel bumpy and curled instead of being a smooth tube?"},{"id":"nose-two-nostrils-stereo","t":"body","q":"Why do you have two nostrils instead of one big one?"},{"id":"nose-warms-air","t":"body","q":"Why does breathing through your nose feel different from breathing through your mouth?"},{"id":"nosebleed-dry-air","t":"body","q":"Why do nosebleeds happen more often in winter?"},{"id":"nosebleed-kiesselbach","t":"body","q":"Why do nosebleeds almost always come from the same small spot?"},{"id":"nosebleed-lean-forward","t":"body","q":"Why does leaning forward, not tipping your head back, make more sense during a nosebleed?"},{"id":"nostril-flare-breathless","t":"body","q":"Why do your nostrils flare open wide when you're out of breath?"},{"id":"numb-foot-clumsy","t":"body","q":"Why does a numb foot feel clumsy to walk on, even once the pain is gone?"},{"id":"olfactory-bulb-limbic","t":"body","q":"Why does your sense of smell feel so wired into your emotions?"},{"id":"olfactory-receptor-types","t":"body","q":"Why can your nose recognise so many different smells with just one small patch of tissue?"},{"id":"optical-illusion-brain","t":"body","q":"Why can a picture trick your brain into seeing something that isn't really there?"},{"id":"own-breath-smell-blind","t":"body","q":"Why is it so hard to smell your own breath just by breathing normally?"},{"id":"papillae-vs-buds","t":"body","q":"Why are the bumps you can see on your tongue not actually your taste buds?"},{"id":"petrichor-rain-smell","t":"body","q":"Why can you smell rain coming before it actually starts?"},{"id":"phantom-itch-cast","t":"body","q":"Why can skin itch underneath a plaster cast where you can't even reach it?"},{"id":"phantom-limb","t":"body","q":"Why can someone still feel an arm or leg that isn't there any more?"},{"id":"phantom-smell","t":"body","q":"Why do some people smell something that isn't actually there?"},{"id":"phantom-vibration","t":"body","q":"Why do you sometimes feel your phone buzz in your pocket when it isn't even there?"},{"id":"photic-sneeze","t":"body","q":"Why do some people sneeze when they step into bright sunlight?"},{"id":"photographic-memory-myth","t":"body","q":"Why doesn't 'photographic memory' really work the way movies show it?"},{"id":"pins-needles-foot","t":"body","q":"Why does your foot fill up with pins and needles after sitting on it?"},{"id":"pitch-frequency","t":"body","q":"Why does how fast something vibrates decide whether a sound is high-pitched or low-pitched?"},{"id":"placebo-pain-relief","t":"body","q":"Why can a sugar pill sometimes actually ease real pain?"},{"id":"plaque-film-morning","t":"body","q":"Why do your teeth feel fuzzy first thing in the morning?"},{"id":"plasma-yellow","t":"body","q":"Why is the liquid part of your blood yellow instead of red?"},{"id":"platelets-fragments","t":"body","q":"Why aren't platelets actually whole cells, just fragments of one?"},{"id":"pleasant-smell-learned","t":"body","q":"Why do people from different places sometimes disagree about whether a smell is pleasant?"},{"id":"pleura-slippery","t":"body","q":"Why do your lungs need a slippery double layer wrapped around them?"},{"id":"postural-tone","t":"body","q":"Why do your muscles need to work even while you're just standing still?"},{"id":"prefrontal-teen","t":"body","q":"Why do teenagers sometimes make riskier decisions than adults might?"},{"id":"premature-breathing","t":"body","q":"Why do some babies born early need extra help just to breathe?"},{"id":"presbycusis","t":"body","q":"Why do many older people find it hard to follow conversation in a noisy room, even before they think their hearing is failing?"},{"id":"proprioception-arm-position","t":"body","q":"Why do you always know where your arm is without looking at it?"},{"id":"proprioception-sense","t":"body","q":"Why can you touch your own nose with your eyes shut, first try, every time?"},{"id":"prune-fingers-grip","t":"body","q":"Why do your fingers go wrinkly in the bath?"},{"id":"prune-only-fingers","t":"body","q":"Why do only your fingers and toes go wrinkly in water, never your arms?"},{"id":"puberty-hair","t":"body","q":"Why does new hair suddenly appear in new places as you grow older?"},{"id":"pulse-points","t":"body","q":"Why can you feel your pulse at your wrist but almost nowhere else?"},{"id":"pupil-muscle","t":"body","q":"Why does a ring of muscle you can't control make your pupil shrink in bright light?"},{"id":"rbc-lifespan","t":"body","q":"Why does every red blood cell get replaced within a few months?"},{"id":"rbc-no-nucleus","t":"body","q":"Why do red blood cells have no nucleus like almost every other cell?"},{"id":"rbc-shape","t":"body","q":"Why are red blood cells shaped like a dented disc instead of a ball?"},{"id":"reading-brain-recycled","t":"body","q":"Why doesn't the brain have a region built specifically for reading?"},{"id":"referred-pain-appendix","t":"body","q":"Why can appendix pain start near your belly button instead of where the appendix is?"},{"id":"referred-pain-arm","t":"body","q":"Why can trouble in your heart be felt as pain down your arm?"},{"id":"reflex-hot-pan","t":"body","q":"Why do you snatch your hand back from something hot before it even hurts?"},{"id":"residual-air","t":"body","q":"Why do your lungs never go completely empty, even after you breathe all the way out?"},{"id":"ribcage-breathe","t":"body","q":"Why does your whole ribcage lift and widen every time you breathe in?"},{"id":"ribs-12-pairs","t":"body","q":"Why do you have exactly twelve pairs of ribs, no more and no less?"},{"id":"rigor-mortis","t":"body","q":"Why do muscles go stiff after someone dies instead of staying soft?"},{"id":"rub-bump-better","t":"body","q":"Why does rubbing a bumped knee actually make it hurt less?"},{"id":"runny-nose-consistency","t":"body","q":"Why does a runny nose sometimes drip thin and watery and other times feel thick and blocked?"},{"id":"saliva-amylase","t":"body","q":"Why does a piece of plain bread start tasting slightly sweet if you chew it for a long time?"},{"id":"saliva-anticipation","t":"body","q":"Why does your mouth water at the smell of dinner cooking, before you've seen any food at all?"},{"id":"saliva-daily-litres","t":"body","q":"Why do you swallow your own spit hundreds of times a day without ever running dry?"},{"id":"saliva-ingredients","t":"body","q":"Why is spit far more complicated than just watery mouth moisture?"},{"id":"saliva-protect-teeth","t":"body","q":"Why is spit one of the best things protecting your teeth?"},{"id":"saliva-wound-lick-myth","t":"body","q":"Why is licking a small cut better than nothing, but nowhere near as good as people think?"},{"id":"salt-craving-sodium","t":"body","q":"Why can your body suddenly crave something salty after a long, sweaty day?"},{"id":"scabs","t":"body","q":"Why do cuts turn into scabs?"},{"id":"scar-no-hair","t":"body","q":"Why can't scars grow hair or freckles?"},{"id":"scar-turns-white","t":"body","q":"Why do old scars turn pale and shiny?"},{"id":"scar-vs-no-scar","t":"body","q":"Why do some cuts leave a scar and others heal without one?"},{"id":"seeing-stars","t":"body","q":"Why do you sometimes 'see stars' after bumping your head?"},{"id":"sensory-homunculus","t":"body","q":"Why do your hands and lips take up so much more brain space than your back?"},{"id":"sensory-overload-tag","t":"body","q":"Why can a scratchy clothing tag feel unbearable to some people and not others?"},{"id":"shark-vs-human-teeth","t":"body","q":"Why do humans only get one replacement set of teeth while some animals keep growing new ones forever?"},{"id":"shiver","t":"body","q":"Why do we shiver when we're cold?"},{"id":"shock-mask-injury","t":"body","q":"Why might you not notice you're hurt until after the danger has passed?"},{"id":"shorter-evening","t":"body","q":"Why are you slightly taller in the morning than at night?"},{"id":"sigh-reset","t":"body","q":"Why do you sigh sometimes without meaning to?"},{"id":"signal-relay-chemical","t":"body","q":"Why are brain signals part electricity and part chemistry?"},{"id":"singers-lung-capacity","t":"body","q":"Why do singers and wind instrument players train their breathing for years?"},{"id":"skin-biggest-organ","t":"body","q":"Why is skin the biggest organ in your body?"},{"id":"skin-colour-equator","t":"body","q":"Why is skin colour, on average, darker closer to the equator?"},{"id":"skin-lips-chap","t":"body","q":"Why do lips get chapped so much faster than the rest of your face?"},{"id":"skin-lips-different","t":"body","q":"Why are your lips a different colour and texture from the rest of your face?"},{"id":"skin-nerve-density","t":"body","q":"Why does a tiny cut on your fingertip hurt more than a big scrape on your back?"},{"id":"skin-oily-sebum","t":"body","q":"Why does your skin feel oily by the end of the day?"},{"id":"skin-palms-pale","t":"body","q":"Why are the palms of your hands and soles of your feet always lighter than the rest of your skin?"},{"id":"skin-receptor-types","t":"body","q":"Why does your skin need so many different kinds of nerve endings?"},{"id":"skin-shedding-unnoticed","t":"body","q":"Why don't you ever notice your skin flaking off?"},{"id":"skin-snap-back","t":"body","q":"Why does skin snap back into place after you pinch it and let go?"},{"id":"skin-stretch-fit","t":"body","q":"Why can skin stretch to fit a growing body without splitting?"},{"id":"skin-tan-fades","t":"body","q":"Why doesn't a suntan last forever?"},{"id":"skin-tan-forms","t":"body","q":"Why does skin turn darker after time in the sun?"},{"id":"skin-three-layers","t":"body","q":"Why does skin have three different layers?"},{"id":"skin-waterproof-bath","t":"body","q":"Why doesn't your body soak up bathwater like a sponge?"},{"id":"skull-puzzle","t":"body","q":"Why is your skull actually made of about twenty separate bones stitched together?"},{"id":"smallest-bone-ear","t":"body","q":"Why is the smallest bone in your whole body hiding inside your ear?"},{"id":"smell-adaptation-house","t":"body","q":"Why can't you smell your own house, but visitors notice it the moment they walk in?"},{"id":"smell-brain-pattern-code","t":"body","q":"Why doesn't your brain need a separate receptor for every single smell that exists?"},{"id":"smell-hunger-stronger","t":"body","q":"Why do food smells seem so much stronger when you're hungry?"},{"id":"smell-loss-age","t":"body","q":"Why do older people often lose some of their sense of smell?"},{"id":"smell-loss-cold","t":"body","q":"Why can't you smell much when you have a blocked nose from a cold?"},{"id":"smell-memory-proust","t":"body","q":"Why can one whiff of a smell bring back a memory you'd completely forgotten?"},{"id":"smell-not-weak-myth","t":"body","q":"Why is it wrong to say humans have a weak sense of smell?"},{"id":"smoke-cilia","t":"body","q":"Why does breathing smoky air leave you coughing for hours afterward?"},{"id":"smoke-wont-wake-you","t":"body","q":"Why doesn't the smell of smoke reliably wake a sleeping person up?"},{"id":"smooth-muscle-gut-control","t":"body","q":"Why can't you make your intestines squeeze on command, no matter how hard you try?"},{"id":"smooth-muscle-swallow","t":"body","q":"Why don't you have to think about squeezing your dinner all the way down?"},{"id":"snatiation-sneeze-meal","t":"body","q":"Why do some people sneeze right after eating a big meal?"},{"id":"sneeze","t":"body","q":"Why do we sneeze?"},{"id":"sniffing-mechanism","t":"body","q":"Why does taking a hard sniff help you smell something better than breathing normally?"},{"id":"snorkel-dead-space","t":"body","q":"Why can't you breathe safely through a long snorkel tube stretching down to a swimming pool floor?"},{"id":"soda-acid-erosion","t":"body","q":"Why can fizzy drinks harm your teeth even the sugar-free kind?"},{"id":"sound-localisation-front-back","t":"body","q":"Why is it harder to tell if a sound came from in front of you or behind you than to tell left from right?"},{"id":"sound-localisation-two-ears","t":"body","q":"Why do you need two ears to work out which direction a sound came from?"},{"id":"sour-acid-mechanism","t":"body","q":"Why does anything acidic, from lemon juice to vinegar, taste sour?"},{"id":"spicy-pain-not-taste","t":"body","q":"Why isn't 'spicy' actually one of your official tastes, even though it feels like the strongest flavour on the plate?"},{"id":"spicy-sweat-nose","t":"body","q":"Why does spicy food make you sweat and your nose run?"},{"id":"spinal-cord-shortcut","t":"body","q":"Why do some of your reactions happen before your brain even finds out?"},{"id":"spine-discs","t":"body","q":"Why do soft cushions sit between every bone in your backbone?"},{"id":"spine-many-bones","t":"body","q":"Why is your backbone built from 33 small bones instead of one long rod?"},{"id":"spine-s-curve","t":"body","q":"Why does your backbone bend into a wavy S-shape instead of standing straight?"},{"id":"spleen-recycle","t":"body","q":"Why does your spleen quietly destroy your own blood cells?"},{"id":"split-brain-surgery","t":"body","q":"Why can cutting the cable between the brain's two halves stop severe seizures?"},{"id":"split-ends","t":"body","q":"Why does hair get split ends?"},{"id":"split-ends-fix","t":"body","q":"Why can't split ends be repaired, only cut off?"},{"id":"spots-puberty","t":"body","q":"Why do spots often show up more as you grow into a teenager?"},{"id":"spots-why-form","t":"body","q":"Why do spots and pimples form on skin?"},{"id":"static-shock-jump","t":"body","q":"Why does a small static shock make you flinch before it even properly hurts?"},{"id":"stereo-headphones-channels","t":"body","q":"Why do headphones send slightly different sound to your left ear and your right ear instead of exactly the same thing?"},{"id":"stereognosis-dark","t":"body","q":"Why can you find your keys in a bag by feel alone, without looking?"},{"id":"stethoscope","t":"body","q":"Why do doctors listen to your heart instead of just feeling your pulse?"},{"id":"stretch-marks","t":"body","q":"Why do stretch marks appear on skin that grows or stretches fast?"},{"id":"sunburn-cloudy-day","t":"body","q":"Why can you get sunburnt on a cloudy day?"},{"id":"sunburn-peel","t":"body","q":"Why does sunburnt skin peel off days later?"},{"id":"sunburn-red","t":"body","q":"Why does skin turn red and sore after too much sun?"},{"id":"sunburn-touch-hurt","t":"body","q":"Why can sunburnt skin hurt even from a soft T-shirt?"},{"id":"supertaster-density","t":"body","q":"Why do some people taste bitter vegetables far more strongly than everyone else at the table?"},{"id":"supertaster-veg-dislike","t":"body","q":"Why do some children refuse vegetables that the rest of the family happily eats?"},{"id":"surfactant-newborn","t":"body","q":"Why don't your smallest air sacs stick shut every time you breathe out?"},{"id":"swallow-nose-seal","t":"body","q":"Why doesn't food or drink come shooting out of your nose every time you swallow?"},{"id":"sweat-armpit-glands","t":"body","q":"Why do your armpits sweat differently from your arms?"},{"id":"sweat-feels-cool","t":"body","q":"Why does sweat make you feel cooler?"},{"id":"sweat-nervous","t":"body","q":"Why do your palms get sweaty when you're nervous, even if you're not hot?"},{"id":"sweat-why-we-sweat","t":"body","q":"Why do we sweat?"},{"id":"sweet-craving-calories","t":"body","q":"Why do humans crave sugary food so strongly, even when they know it isn't the healthiest choice?"},{"id":"swimmers-ear","t":"body","q":"Why can water trapped in your ear after swimming turn into a painful infection?"},{"id":"synapse-gap","t":"body","q":"Why don't the brain cells that talk to each other actually touch?"},{"id":"tailbone","t":"body","q":"Why do you still have a tiny tailbone if humans don't have tails?"},{"id":"talking-breath-control","t":"body","q":"Why do you sometimes run out of breath partway through a long sentence?"},{"id":"tartar-hardens","t":"body","q":"Why does plaque turn into something a toothbrush can no longer scrub off?"},{"id":"taste-adaptation-fade","t":"body","q":"Why do the last few chips in the packet taste less salty than the first few?"},{"id":"taste-bud-count","t":"body","q":"Why do some people have far more taste buds than others?"},{"id":"taste-bud-renew","t":"body","q":"Why don't taste buds wear out from being scalded by hot food all the time?"},{"id":"taste-buds-beyond-tongue","t":"body","q":"Why do you have taste buds in places other than your tongue?"},{"id":"taste-fade-age","t":"body","q":"Why might food taste blander to a grandparent than it does to a young child eating the exact same meal?"},{"id":"taste-map-myth","t":"body","q":"Why is the tongue taste map you might have learned at school completely wrong?"},{"id":"taste-memory-emotion","t":"body","q":"Why can one particular taste suddenly bring back a strong memory from years ago?"},{"id":"taste-pore-microvilli","t":"body","q":"Why can a taste bud detect a flavour chemical without any of its cells actually touching your food?"},{"id":"teeth-fall","t":"body","q":"Why do our teeth fall out?"},{"id":"teeth-not-bones","t":"body","q":"Why aren't your teeth actually counted as bones?"},{"id":"teeth-tell-age","t":"body","q":"Why can scientists estimate someone's age just by looking at their teeth?"},{"id":"ten-percent-myth","t":"body","q":"Why is it wrong to say we only use 10 percent of our brains?"},{"id":"tendon-basic","t":"body","q":"Why is a muscle joined to bone by a tendon instead of attaching straight on?"},{"id":"tendon-ligament-mixup","t":"body","q":"Why do people mix up tendons and ligaments when they do completely different jobs?"},{"id":"thirst-mouth-signal","t":"body","q":"Why does a sip of water make thirst vanish almost instantly, long before it could possibly reach your bloodstream?"},{"id":"tickle-self","t":"body","q":"Why can't I tickle myself?"},{"id":"ticklish-feet","t":"body","q":"Why are the soles of your feet often the most ticklish part of you?"},{"id":"tinnitus-after-concert","t":"body","q":"Why do your ears ring for hours after a loud concert, even once the noise has stopped?"},{"id":"tinnitus-silence-brain","t":"body","q":"Why do some people hear a faint ringing in total silence, even with hearing that's never been damaged by noise?"},{"id":"tongue-bite-reflex","t":"body","q":"Why don't you bite your own tongue constantly while chewing, given how close your teeth pass to it?"},{"id":"tongue-heat-sensitivity-tip","t":"body","q":"Why does the very tip of your tongue seem to notice hot food faster than further back?"},{"id":"tongue-hydrostat-muscle","t":"body","q":"Why can your tongue bend, twist and curl in almost any direction without any joints or bones?"},{"id":"tongue-hyoid-anchor","t":"body","q":"Why is the bone your tongue is anchored to unlike every other bone in your body?"},{"id":"tongue-print-pattern","t":"body","q":"Why might your tongue's surface pattern be just as unique as your fingerprint?"},{"id":"tongue-roll-genetics-myth","t":"body","q":"Why was tongue-rolling wrongly taught as a simple example of genetics for decades?"},{"id":"tongue-strongest-myth","t":"body","q":"Why is it a myth that your tongue is the strongest muscle in your body?"},{"id":"tongue-stuck-cold-metal","t":"body","q":"Why does a wet tongue stick fast to very cold metal, sometimes badly enough to hurt?"},{"id":"tongue-tie-frenulum","t":"body","q":"Why can some babies struggle to feed properly because of a small piece of tissue under the tongue?"},{"id":"tongue-touch-sensitive","t":"body","q":"Why is your tongue one of the most touch-sensitive parts of your body?"},{"id":"tongue-twister-hard","t":"body","q":"Why do tongue twisters trip you up even when you know exactly what you're trying to say?"},{"id":"tongue-white-coating","t":"body","q":"Why does your tongue sometimes look coated in a thin white film?"},{"id":"tooth-abscess-swelling","t":"body","q":"Why can an infected tooth cause your whole cheek to swell up?"},{"id":"tooth-color-dentin","t":"body","q":"Why aren't teeth actually pure white?"},{"id":"tooth-count-20-32","t":"body","q":"Why do children end up with 20 teeth while adults have 32?"},{"id":"tooth-decay-catching","t":"body","q":"Why can tooth decay spread a little like an infection between people?"},{"id":"tooth-enamel-formed-early","t":"body","q":"Why was the enamel on your adult teeth actually made years before those teeth ever appeared?"},{"id":"tooth-eruption-order","t":"body","q":"Why do teeth grow in in a fixed order rather than all at once?"},{"id":"tooth-fairy-tradition","t":"body","q":"Why do so many cultures have their own tradition for a lost tooth?"},{"id":"tooth-pulp-nerve","t":"body","q":"Why do teeth have living tissue hidden inside something so hard?"},{"id":"tooth-root-anchor","t":"body","q":"Why is most of a tooth actually hidden inside your jaw?"},{"id":"tooth-sensitivity-cold","t":"body","q":"Why do some teeth sting sharply when you drink something cold?"},{"id":"tooth-shapes-jobs","t":"body","q":"Why aren't all your teeth the same shape?"},{"id":"tooth-wiggle-ligament","t":"body","q":"Why does a loose tooth wiggle for weeks before it finally comes out?"},{"id":"tooth-xray-cavity","t":"body","q":"Why can an X-ray find a cavity you can't feel or see yet?"},{"id":"toothache-pain-intense","t":"body","q":"Why can a toothache hurt so much more than a cut of the same size?"},{"id":"toothache-worse-night","t":"body","q":"Why does a toothache often feel worse once you're lying down at night?"},{"id":"toothbrush-bristles-splay","t":"body","q":"Why do a toothbrush's bristles fan outward after just a few months?"},{"id":"toothpaste-oj-bitter","t":"body","q":"Why does orange juice taste horribly bitter if you drink it right after brushing your teeth?"},{"id":"touch-vs-push","t":"body","q":"Why can you tell a light touch from a firm push, even with your eyes shut?"},{"id":"trachea-rings","t":"body","q":"Why is your windpipe held open by rings instead of being a floppy tube?"},{"id":"transfusion-match","t":"body","q":"Why can't a doctor give you just any blood type in a transfusion?"},{"id":"trillion-smells-study","t":"body","q":"Why was the old claim that humans can smell about 10,000 different odours wrong?"},{"id":"tummy-rumble","t":"body","q":"Why does my tummy rumble?"},{"id":"two-eyes","t":"body","q":"Why do we have two eyes?"},{"id":"two-fibre-pain","t":"body","q":"Why does stubbing your toe hurt twice — a sharp pain, then a dull ache?"},{"id":"umami-ikeda","t":"body","q":"Why did it take Western science decades to accept a taste that Japanese cooks already knew about?"},{"id":"underwater-muffled","t":"body","q":"Why do sounds seem muffled and strange when your head is underwater?"},{"id":"universal-donor","t":"body","q":"Why is one blood type called the universal donor?"},{"id":"unpleasant-smell-evolution","t":"body","q":"Why do rotten food and sulfur smells feel disgusting to almost everyone?"},{"id":"vaccines","t":"body","q":"Why does a needle stop you getting sick?"},{"id":"vein-valves","t":"body","q":"Why do veins have one-way valves inside them but arteries don't?"},{"id":"vessel-length-myth","t":"body","q":"Why don't your blood vessels really stretch around the Earth twice?"},{"id":"vestibular-eye-reflex-vor","t":"body","q":"Why do your eyes stay locked on something steady even while you shake your head?"},{"id":"vibration-through-table","t":"body","q":"Why can you feel a phone buzzing through a table without touching it directly?"},{"id":"visceral-vs-skin-pain","t":"body","q":"Why is it so hard to point to exactly where a stomach ache hurts?"},{"id":"voice-changes","t":"body","q":"Why does your voice get deeper as you grow up?"},{"id":"volatile-molecules-smell","t":"body","q":"Why do some things, like glass or a spoon, have no smell at all?"},{"id":"warm-cold-buttons","t":"body","q":"Why does your skin have separate nerve endings for warm and cold?"},{"id":"warm-food-smells-more","t":"body","q":"Why does hot food smell so much stronger than the same food cold?"},{"id":"water-taste-myth","t":"body","q":"Why does water sometimes seem to have a faint taste, even though it's supposedly tasteless?"},{"id":"wet-nose-smell-better","t":"body","q":"Why does a dry, stuffy nose make it harder to smell things clearly?"},{"id":"whale-breath-hold","t":"body","q":"Why can a whale hold its breath for over an hour while you can barely manage a minute?"},{"id":"white-noise-mask","t":"body","q":"Why can playing a steady hissing sound help you sleep through other noises at night?"},{"id":"whitening-toothpaste-myth","t":"body","q":"Why can't whitening toothpaste truly change the natural colour of your teeth?"},{"id":"why-breathe","t":"body","q":"Why do we have to breathe?"},{"id":"why-sleep","t":"body","q":"Why do we have to sleep?"},{"id":"wisdom-teeth-impacted","t":"body","q":"Why do wisdom teeth so often need to be taken out?"},{"id":"wisdom-teeth-late","t":"body","q":"Why do wisdom teeth wait until you're almost grown up to arrive?"},{"id":"wisdom-teeth-name","t":"body","q":"Why are wisdom teeth called wisdom teeth at all?"},{"id":"wrong-pipe-cough","t":"body","q":"Why do you cough so violently when a drink 'goes down the wrong pipe'?"},{"id":"xray-bones","t":"body","q":"Why do X-rays show your bones clearly but barely show your skin at all?"},{"id":"xray-shield","t":"body","q":"Why do dentists step behind a wall or wear a heavy apron when they take an X-ray?"},{"id":"yawn-contagious","t":"body","q":"Why do you yawn when someone else does?"},{"id":"yawn-not-oxygen","t":"body","q":"Why do we yawn, if it isn't really about needing more oxygen?"},{"id":"3d-glasses","t":"machines","q":"Why do 3D glasses make a film pop out?"},{"id":"4k-vs-1080p-naming","t":"machines","q":"Why does '4K' mean four times as many pixels as '1080p', not four times the number?"},{"id":"9v-tongue-tingle","t":"machines","q":"Why does touching a 9-volt battery to your tongue give a tiny tingle but a wall socket can kill?"},{"id":"abs-pulsing-brakes","t":"machines","q":"Why does a car's brake pedal sometimes judder under your foot during a hard stop?"},{"id":"accelerometer-chip","t":"machines","q":"Why can a phone sense which way is down with no moving parts you'd ever notice?"},{"id":"active-vs-passive-stylus","t":"machines","q":"Why do some styluses need their own battery while others are just a stick with a tip?"},{"id":"aeroplane-mode-why","t":"machines","q":"Why do you have to switch your phone to aeroplane mode before a flight takes off?"},{"id":"aeroplane-mode-wifi","t":"machines","q":"Why can you still use wifi on a plane even with your phone in aeroplane mode?"},{"id":"ai-adversarial-sticker","t":"machines","q":"Why can a small sticker trick an AI into misreading a stop sign?"},{"id":"ai-art-extra-fingers","t":"machines","q":"Why do AI-drawn pictures sometimes give people extra fingers?"},{"id":"ai-bias-data","t":"machines","q":"Why can an AI end up unfair without anyone programming it to be?"},{"id":"ai-energy-cost","t":"machines","q":"Why can training a single big AI use as much electricity as a small town?"},{"id":"ai-knowledge-cutoff","t":"machines","q":"Why doesn't a chatbot know about something that happened yesterday?"},{"id":"ai-needs-data","t":"machines","q":"Why does an AI need to see millions of examples before it can do anything useful?"},{"id":"ai-talks","t":"machines","q":"Why can a computer talk back to you?"},{"id":"ai-understanding-unknown","t":"machines","q":"Why can't scientists agree on whether an AI truly understands anything at all?"},{"id":"ai-writing-style-mimicry","t":"machines","q":"Why can an AI write a poem 'in the style' of a famous author it has never met?"},{"id":"air-traffic-control-spacing","t":"machines","q":"Why do air traffic controllers keep planes so many kilometres apart in the sky?"},{"id":"airbag-deploy-speed","t":"machines","q":"Why can an airbag inflate fast enough to protect you in a crash that lasts only a fraction of a second?"},{"id":"alternator-charges-battery","t":"machines","q":"Why doesn't a car's battery go flat after hours of driving with the lights and radio on?"},{"id":"aluminium-can-not-stick-fridge","t":"machines","q":"Why does a steel drink can stick to a fridge magnet while an aluminium one doesn't?"},{"id":"artificial-intelligence-name","t":"machines","q":"Why is it called 'artificial' intelligence?"},{"id":"asimov-laws-fiction","t":"machines","q":"Why aren't Isaac Asimov's famous Three Laws of Robotics built into real robots?"},{"id":"autofocus-hunt","t":"machines","q":"Why does a camera lens sometimes slide in and out before it focuses?"},{"id":"autopilot-hours","t":"machines","q":"Why can an airliner fly for hours with nobody touching the controls?"},{"id":"autosave-recovery","t":"machines","q":"Why can some programs recover your work after a crash, even though you never hit save?"},{"id":"balloon-hair-static","t":"machines","q":"Why does a balloon rubbed on hair stick to a wall?"},{"id":"banking-to-turn","t":"machines","q":"Why does a plane tip sideways to turn instead of steering flat like a car?"},{"id":"bar-magnet-red-blue-paint","t":"machines","q":"Why are the two ends of a classic bar magnet often painted red and blue?"},{"id":"barcode-scanner-laser","t":"machines","q":"Why does a checkout scanner beep as it reads a barcode?"},{"id":"barcode-stripe-widths","t":"machines","q":"Why do barcode stripes come in different widths?"},{"id":"bathroom-socket-water","t":"machines","q":"Why are power sockets kept away from water in bathrooms?"},{"id":"batt-aa-vs-aaa-voltage","t":"machines","q":"Why do a AA and a AAA battery both give 1.5 volts despite being different sizes?"},{"id":"batt-alkaline-chem","t":"machines","q":"Why does an ordinary torch battery use zinc and manganese dioxide?"},{"id":"batt-bms","t":"machines","q":"Why does a phone battery have a tiny circuit board glued to it?"},{"id":"batt-button-cell","t":"machines","q":"Why can a watch battery the size of a fingernail last for years?"},{"id":"batt-c-rate","t":"machines","q":"Why can't some small batteries deliver power fast enough for high-drain gadgets like power tools?"},{"id":"batt-calendar-aging","t":"machines","q":"Why does an unused spare phone battery still wear out sitting in a drawer for years?"},{"id":"batt-capacitor-vs-battery","t":"machines","q":"Why can't a capacitor simply replace a battery in most gadgets?"},{"id":"batt-cold-weather","t":"machines","q":"Why do batteries seem to lose power faster in 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the fridge actually make them last longer?"},{"id":"batt-graphite-anode","t":"machines","q":"Why does a lithium-ion battery need graphite inside it, the same material as pencil lead?"},{"id":"batt-internal-resistance","t":"machines","q":"Why does a battery's voltage dip the moment you switch on something power-hungry?"},{"id":"batt-laptop-multi-cell","t":"machines","q":"Why do laptop batteries contain several small cylindrical cells instead of one big block?"},{"id":"batt-lead-acid-car","t":"machines","q":"Why does a car battery use six connected cells instead of one big one?"},{"id":"batt-lithium-ion-chem","t":"machines","q":"Why do lithium-ion batteries pack so much more energy into the same size than old batteries?"},{"id":"batt-low-self-discharge","t":"machines","q":"Why do some rechargeable batteries stay charged on a shelf for a year while others go flat in weeks?"},{"id":"batt-magnet-myth","t":"machines","q":"Why can't a magnet be used to recharge a battery?"},{"id":"batt-mah","t":"machines","q":"Why is a battery's capacity measured in milliamp-hours instead of just written as a running time?"},{"id":"batt-mah-vs-runtime","t":"machines","q":"Why can two batteries with the same mAh rating not last the same amount of time?"},{"id":"batt-memory-myth","t":"machines","q":"Why is it fine to top up your phone battery before it's completely empty?"},{"id":"batt-mixing-old-new","t":"machines","q":"Why shouldn't you mix an old, tired battery with a fresh one in the same device?"},{"id":"batt-nicad-vs-nimh","t":"machines","q":"Why did nickel-cadmium rechargeable batteries get replaced by nickel-metal hydride ones?"},{"id":"batt-nimh-voltage-diff","t":"machines","q":"Why do rechargeable AA batteries often show 1.2 volts instead of the usual 1.5?"},{"id":"batt-not-tank","t":"machines","q":"Why isn't a battery just a tiny tank of stored electricity?"},{"id":"batt-over-discharge-damage","t":"machines","q":"Why can leaving a rechargeable battery fully drained for months genuinely ruin it?"},{"id":"batt-overnight-charge","t":"machines","q":"Why doesn't leaving your phone charging all night ruin the battery?"},{"id":"batt-parallel-capacity","t":"machines","q":"Why do some battery packs wire cells side by side instead of stacking them end to end?"},{"id":"batt-percentage-jump","t":"machines","q":"Why can a phone's battery percentage suddenly jump from 20% down to 5% in a few minutes?"},{"id":"batt-plane-restriction","t":"machines","q":"Why are spare lithium batteries banned from checked luggage on planes?"},{"id":"batt-recycling-toxic","t":"machines","q":"Why shouldn't old batteries go in the regular rubbish bin?"},{"id":"batt-separator","t":"machines","q":"Why is there a thin plastic sheet inside every battery, separating its two ends?"},{"id":"batt-series-voltage","t":"machines","q":"Why do two batteries stacked end to end in a torch add up to more volts?"},{"id":"batt-shake-torch","t":"machines","q":"Why does tapping an old torch sometimes make a dying battery flicker back on?"},{"id":"batt-shelf-life","t":"machines","q":"Why do unused batteries slowly lose their charge just sitting in a drawer?"},{"id":"batt-solid-state-future","t":"machines","q":"Why are some new batteries replacing their liquid chemicals with a solid?"},{"id":"batt-swelling","t":"machines","q":"Why does an old phone battery sometimes swell up like a pillow?"},{"id":"batt-thermal-runaway","t":"machines","q":"Why is puncturing a lithium battery so dangerous?"},{"id":"batt-windup-contrast","t":"machines","q":"Why doesn't a wind-up torch need a battery at all?"},{"id":"batt-wrong-way-round","t":"machines","q":"Why does a torch do nothing if you put one battery in facing the wrong way?"},{"id":"battery-die","t":"machines","q":"Why do batteries go flat?"},{"id":"battery-wears-out","t":"machines","q":"Why does an old phone's battery not last a day any more, even though it once did?"},{"id":"beauty-filter-face","t":"machines","q":"Why can a phone filter instantly smooth skin or reshape a face while filming?"},{"id":"bifocal-glasses","t":"machines","q":"Why do some glasses have a visible line splitting the lens in two?"},{"id":"bikes-balance","t":"machines","q":"Why doesn't a moving bike fall over?"},{"id":"binary","t":"machines","q":"Why does a computer only understand 1s and 0s?"},{"id":"binoculars-prism","t":"machines","q":"Why are binoculars so much shorter than the telescopes squashed inside them?"},{"id":"bird-power-line-safe","t":"machines","q":"Why can a bird perch safely on a high-voltage power line?"},{"id":"bird-strike-engine-testing","t":"machines","q":"Why are jet engines deliberately blasted with chicken carcasses before they're allowed to fly?"},{"id":"birds-flap-planes-dont","t":"machines","q":"Why can birds fly by flapping while a plane's wings just stay perfectly still?"},{"id":"black-bars-cinema-widescreen","t":"machines","q":"Why do some movies leave black bars at the top and bottom, even on a widescreen TV?"},{"id":"black-bars-old-show-new-tv","t":"machines","q":"Why do black bars appear down the sides of an old show played on a new TV?"},{"id":"black-box","t":"machines","q":"Why does a plane's black box survive a crash?"},{"id":"black-box-orange","t":"machines","q":"Why is a plane's 'black box' actually painted bright orange?"},{"id":"bluetooth-audio-compressed","t":"machines","q":"Why does music sometimes sound worse over Bluetooth headphones than a wire?"},{"id":"boats-float","t":"machines","q":"Why do metal ships float?"},{"id":"bomb-disposal-teleoperation","t":"machines","q":"Why is a bomb disposal robot controlled by a person, not left to decide anything on its own?"},{"id":"boot-up","t":"machines","q":"Why does turning on a computer take longer than turning on a light?"},{"id":"brakes","t":"machines","q":"Why does a car stop when you press the brake?"},{"id":"breaker-trip-switch","t":"machines","q":"Why does a circuit breaker trip and switch itself 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cabin need to be artificially pressurised at all?"},{"id":"cabin-window-tiny-hole","t":"machines","q":"Why does every plane cabin window have a tiny hole in the bottom corner?"},{"id":"cable-landing-station","t":"machines","q":"Why do undersea cables come ashore through a handful of quiet, unmarked buildings?"},{"id":"call-paging","t":"machines","q":"Why does only your phone ring when someone calls your number, and not every phone nearby?"},{"id":"call-speed-of-light","t":"machines","q":"Why can a phone call reach someone on the other side of the world in about a second?"},{"id":"camera-flash-capacitor-charge","t":"machines","q":"Why does a camera flash need a moment to charge before it can fire again?"},{"id":"camera-obscura-history","t":"machines","q":"Why did painters centuries ago use a dark box or room to trace a picture?"},{"id":"camera-screen-dark-bars","t":"machines","q":"Why do screens show dark moving bars when filmed on a phone 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speakers?"},{"id":"catalytic-converter-cleans-exhaust","t":"machines","q":"Why does a car have a metal box under it filled with a honeycomb of tiny holes?"},{"id":"cd-dvd-laser-read","t":"machines","q":"Why does a CD player use a laser instead of a needle?"},{"id":"cdn-copies-worldwide","t":"machines","q":"Why do big websites keep copies of themselves in dozens of countries?"},{"id":"charger-warm","t":"machines","q":"Why does a phone charger's plug get warm while it's working?"},{"id":"cheap-monitor-ghost-trail","t":"machines","q":"Why do some fast-moving objects leave a ghostly trail on a cheap monitor?"},{"id":"chess-ai-no-awareness","t":"machines","q":"Why doesn't a chess computer know it's playing a game?"},{"id":"chip-billions","t":"machines","q":"Why can a chip the size of a fingernail hold billions of switches?"},{"id":"chip-layers","t":"machines","q":"Why does a computer chip have dozens of layers stacked on top of each other?"},{"id":"chromatic-fringe","t":"machines","q":"Why do cheaper camera lenses leave purple or green edges on bright objects?"},{"id":"circuit-loop-need","t":"machines","q":"Why does electricity need a complete loop to flow at all?"},{"id":"circuit-vs-packet-switching","t":"machines","q":"Why doesn't the internet reserve you a private wire the way an old phone call did?"},{"id":"clean-room-chips","t":"machines","q":"Why are computer chips built in rooms cleaner than a hospital operating theatre?"},{"id":"clock-speed-ghz","t":"machines","q":"Why is a computer's speed measured in GHz?"},{"id":"clocks-time","t":"machines","q":"Why does a clock keep time?"},{"id":"close-selfie-big-nose","t":"machines","q":"Why do close-up selfies make your nose look bigger than it really is?"},{"id":"closing-apps-myth","t":"machines","q":"Why doesn't closing all your open apps actually make your phone run faster?"},{"id":"cloud-data-centre-size","t":"machines","q":"Why are cloud data centres often as big as a football 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does a contact lens work the same as glasses sitting right on the eye?"},{"id":"contrails-form-2","t":"machines","q":"Why do planes leave white trails across the sky?"},{"id":"controlled-burn-not-explosion","t":"machines","q":"Why don't the flames inside a car engine actually blow it apart?"},{"id":"copper-wires-electricity","t":"machines","q":"Why is copper used inside almost every electrical wire?"},{"id":"cpu-clock-tick","t":"machines","q":"Why does a CPU need an internal clock ticking to work at all?"},{"id":"cpu-cores","t":"machines","q":"Why do modern computers have several processor 'cores' instead of one?"},{"id":"cpu-not-brain","t":"machines","q":"Why do we call the CPU a computer's 'brain' even though it can't think?"},{"id":"credit-card-magnetic-stripe-wipe","t":"machines","q":"Why can a strong magnet stop a card's magnetic stripe from working?"},{"id":"cruise-altitude-35000","t":"machines","q":"Why do airliners cruise at around 10 kilometres up rather than lower or 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summer?"},{"id":"dust-spot-sensor","t":"machines","q":"Why does one speck of dust show up as the same dark blob in every photo?"},{"id":"earbud-tiny-speaker","t":"machines","q":"Why can an earbud smaller than a coin still produce deep bass?"},{"id":"ears-pop-flight","t":"machines","q":"Why do your ears pop when a plane takes off or lands?"},{"id":"earth-core-dynamo-magnet","t":"machines","q":"Why does the whole Earth act like a giant magnet in the first place?"},{"id":"earth-magnetic-field-flips","t":"machines","q":"Why did Earth's magnetic north and south poles swap places in the past?"},{"id":"edge-light-guide-panel","t":"machines","q":"Why does light from LEDs at the edge of a screen reach evenly all the way across it?"},{"id":"eink-page-stays-power-off","t":"machines","q":"Why does an e-ink page stay visible even after the device is switched off?"},{"id":"eink-sunlight-readable","t":"machines","q":"Why is an e-ink screen easier to read in bright sunlight than a phone 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can an email take minutes to arrive instead of appearing straight away?"},{"id":"emergency-any-tower","t":"machines","q":"Why can you sometimes still call an emergency number even when your phone shows 'no service'?"},{"id":"emergency-auto-locate","t":"machines","q":"Why can emergency services often find you even if you can't describe where you are?"},{"id":"emergency-no-sim","t":"machines","q":"Why can a phone with no SIM card at all still dial an emergency number?"},{"id":"encryption-key","t":"machines","q":"Why can two computers agree on a secret code without ever meeting?"},{"id":"encryption-lock","t":"machines","q":"Why can't someone spying on your wifi read your messages?"},{"id":"endoscope-fibre-camera","t":"machines","q":"Why can doctors see inside your body with a long, thin, bendy tube?"},{"id":"engine-failure-plane-glides","t":"machines","q":"Why doesn't a plane simply drop out of the sky if an engine stops working?"},{"id":"engine-four-stroke","t":"machines","q":"Why does a car engine only get one power stroke for every four strokes of the piston?"},{"id":"engine-idle-still-running","t":"machines","q":"Why does an engine keep running, using fuel, even when the car isn't moving at all?"},{"id":"engine-knock-pinging","t":"machines","q":"Why does an engine sometimes make a strange metallic pinging or rattling sound under load?"},{"id":"engine-oil-lubrication","t":"machines","q":"Why does an engine need oil if it already has petrol?"},{"id":"engines","t":"machines","q":"Why does a car need petrol?"},{"id":"ereader-no-backlight","t":"machines","q":"Why doesn't an e-reader need a backlight to be readable?"},{"id":"ereader-slow-page-turn","t":"machines","q":"Why does turning a page on an e-reader look slower than swiping a phone?"},{"id":"esim-no-card","t":"machines","q":"Why can some new phones connect to a network without any physical SIM card at all?"},{"id":"ev-heavy-battery","t":"machines","q":"Why do electric cars usually weigh more than similar-sized 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100%?"},{"id":"fibre-optic-bend-light","t":"machines","q":"Why doesn't light escape out the sides of a bent fibre optic cable?"},{"id":"fibre-optic-internet-speed","t":"machines","q":"Why is fibre internet so much faster than old copper phone lines?"},{"id":"fibre-optic-light-signal","t":"machines","q":"Why do internet cables under the ocean carry light instead of electricity?"},{"id":"film-negative-colours","t":"machines","q":"Why do old photo negatives show the opposite colours?"},{"id":"film-roll-count","t":"machines","q":"Why could old film cameras only take a fixed number of photos, like 24 or 36?"},{"id":"fingerprint-sensor","t":"machines","q":"Why can a tiny sensor tell your fingerprint apart from everyone else's?"},{"id":"first-industrial-robot","t":"machines","q":"Why was the very first industrial robot built to do only one dangerous job?"},{"id":"fisheye-curve","t":"machines","q":"Why does a very wide-angle lens bend straight lines into 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strongly on one side but feel almost powerless on the other?"},{"id":"fuel-injection-precision","t":"machines","q":"Why do modern engines spray fuel through tiny nozzles instead of just mixing it with air in a bowl?"},{"id":"funhouse-mirror-curve","t":"machines","q":"Why do curved mirrors at fun parks stretch or squash your reflection?"},{"id":"fuse-melts-purpose","t":"machines","q":"Why does a fuse deliberately melt on purpose?"},{"id":"game-ai-milestones","t":"machines","q":"Why did it take computers so much longer to beat humans at the game Go than at chess?"},{"id":"gaming-screen-144hz","t":"machines","q":"Why do some gaming screens redraw the picture 144 times every second?"},{"id":"gecko-grip-robot","t":"machines","q":"Why can some robots climb straight up a smooth glass wall?"},{"id":"generative-ai-new-image","t":"machines","q":"Why can an AI create a picture that has never existed before, instead of just copying one?"},{"id":"generator-spinning-magnet","t":"machines","q":"Why does spinning a magnet inside a coil of wire make electricity appear in the wire?"},{"id":"glass-back-wireless","t":"machines","q":"Why did phone makers bring back glass on the back of phones after years of plastic and metal?"},{"id":"glass-bends-light-refraction","t":"machines","q":"Why does light bend when it passes into glass?"},{"id":"glass-clear","t":"machines","q":"Why can you see through glass?"},{"id":"glasses-fog-breath","t":"machines","q":"Why do glasses fog up when you breathe out in the cold?"},{"id":"glasses-glare-photo","t":"machines","q":"Why do glasses sometimes show a bright glare blocking the eyes in a photo?"},{"id":"glasses-history-invention","t":"machines","q":"Why did glasses take so long to invent, when curved glass had existed for ages?"},{"id":"glasses-long-sight","t":"machines","q":"Why do some people's glasses make their eyes look bigger through the lens?"},{"id":"glasses-off-shelf-reading","t":"machines","q":"Why can you buy reading glasses off a shelf 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magnets?"},{"id":"harddrive-click","t":"machines","q":"Why do old hard drives click and whirr while they work?"},{"id":"hdr-mode","t":"machines","q":"Why can a phone photo show a bright sky and a dark room at the same time?"},{"id":"headlight-halogen-vs-led","t":"machines","q":"Why do some cars' headlights look warm and yellowish while others look bright white or bluish?"},{"id":"heavy-jets-long-takeoff","t":"machines","q":"Why can't a fully loaded jumbo jet take off in as short a distance as a small plane?"},{"id":"helicopter-hover","t":"machines","q":"Why can a helicopter hover?"},{"id":"hindenburg-hydrogen","t":"machines","q":"Why did the airship Hindenburg burn so fast in 1937?"},{"id":"home-router-shared-address","t":"machines","q":"Why can every device in your house share just one address to the outside internet?"},{"id":"horseshoe-magnet-shape","t":"machines","q":"Why are some magnets bent into a horseshoe shape instead of being a straight bar?"},{"id":"hot-air-balloon-no-wings","t":"machines","q":"Why can a hot air balloon rise without any wings at all?"},{"id":"house-parallel-circuits","t":"machines","q":"Why does a house wire its rooms in parallel instead of one giant loop?"},{"id":"https-padlock","t":"machines","q":"Why does a padlock icon appear next to some website addresses?"},{"id":"humanoid-balance","t":"machines","q":"Why is it so hard to build a robot that walks steadily on two legs?"},{"id":"hybrid-power-switch","t":"machines","q":"Why does a hybrid car sometimes run silently on electricity and other times switch its petrol engine on?"},{"id":"hyperlink-web-shape","t":"machines","q":"Why is the web shaped like a tangle of links instead of a straight line?"},{"id":"internet","t":"machines","q":"Why does the internet work?"},{"id":"internet-exchange","t":"machines","q":"Why do rival internet companies meet inside special buildings to hand traffic to each other?"},{"id":"internet-survives-damage","t":"machines","q":"Why can the internet keep working even when a cable or country drops offline?"},{"id":"ip-address-need","t":"machines","q":"Why does every device online need its own address?"},{"id":"ip-address-running-out","t":"machines","q":"Why did the world start running out of internet addresses?"},{"id":"ip-rating","t":"machines","q":"Why does a phone's box show something like 'IP68' next to a picture of a water drop?"},{"id":"ipv6-huge","t":"machines","q":"Why was the internet's new address system built big enough for trillions of trillions of devices?"},{"id":"ir-night-vision-glow","t":"machines","q":"Why do some security cameras give off a faint reddish glow at night?"},{"id":"iso-grain-noise","t":"machines","q":"Why do photos taken in the dark look grainy and speckled?"},{"id":"jet-engine-fan-blades","t":"machines","q":"Why does a jet engine have a huge spinning fan at the very front?"},{"id":"jet-fuel-kerosene","t":"machines","q":"Why do jet engines burn a different fuel from the petrol used in a car?"},{"id":"jpg-not-compress","t":"machines","q":"Why won't zipping a photo or video shrink it much further?"},{"id":"jump-leads-correct-order","t":"machines","q":"Why do jump leads need to be connected in the right order?"},{"id":"jumper-crackle-winter","t":"machines","q":"Why does a wool jumper crackle when you pull it off in winter?"},{"id":"kaleidoscope-mirrors","t":"machines","q":"Why does a kaleidoscope turn a few loose beads into a symmetrical pattern?"},{"id":"keyboard-signal","t":"machines","q":"Why does a computer know exactly which key you pressed?"},{"id":"keys-lock","t":"machines","q":"Why does only your key open your door?"},{"id":"kite-needs-angle","t":"machines","q":"Why does a kite need to be angled into the wind rather than held flat?"},{"id":"landing-gear-retracts","t":"machines","q":"Why do a plane's wheels fold up and disappear soon after takeoff?"},{"id":"laptop-throttle","t":"machines","q":"Why does a laptop deliberately slow itself down when it gets hot?"},{"id":"laser-beam-not-visible-air","t":"machines","q":"Why can't you see a laser beam glowing through clean air, like in the movies?"},{"id":"laser-beam-tight-narrow","t":"machines","q":"Why does a laser pointer's dot stay small from right across a room?"},{"id":"laser-cutting-industrial","t":"machines","q":"Why can a laser cut through metal without ever touching it?"},{"id":"laser-eye-surgery-lasik","t":"machines","q":"Why can a laser fix blurry eyesight without a scalpel?"},{"id":"laser-holography","t":"machines","q":"Why can a hologram show a 3D image from a laser and flat film?"},{"id":"laser-how-it-works","t":"machines","q":"Why is laser light different from the light in an ordinary torch?"},{"id":"laser-level-tool","t":"machines","q":"Why can a laser level draw a perfectly straight line across a wall?"},{"id":"laser-measuring-tool","t":"machines","q":"Why can a handheld laser tool measure a room instantly?"},{"id":"laser-one-colour","t":"machines","q":"Why is a laser always a single pure colour?"},{"id":"laser-pointer-cat","t":"machines","q":"Why do cats chase a laser pointer dot but never manage to catch it?"},{"id":"laser-pointer-safety","t":"machines","q":"Why should you never point a laser pointer at someone's eyes?"},{"id":"laser-printer-how","t":"machines","q":"Why does a laser printer need a laser, when it prints with powder?"},{"id":"laser-show-colour","t":"machines","q":"Why can a laser light show produce so many colours from just a few lasers?"},{"id":"laser-tattoo-removal","t":"machines","q":"Why does removing a tattoo with a laser take several visits?"},{"id":"latency-distance","t":"machines","q":"Why does the internet still take time to respond, even at the speed of light?"},{"id":"lcd-backlight-black","t":"machines","q":"Why do LCD screens need a light behind them just to show 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green paint makes brown?"},{"id":"lightbulb-glow","t":"machines","q":"Why does a light bulb glow?"},{"id":"lightning-rod-protect","t":"machines","q":"Why does a metal rod on a roof protect a whole building from lightning?"},{"id":"lights-instant","t":"machines","q":"Why do lights come on instantly?"},{"id":"live-stream-delay","t":"machines","q":"Why is a live stream actually several seconds behind the real event?"},{"id":"lodestone-natural-magnet","t":"machines","q":"Why were some rocks already magnetic long before anyone learned to make a magnet?"},{"id":"logic-gates-add","t":"machines","q":"Why can wiring switches together add up numbers?"},{"id":"long-exposure-trails","t":"machines","q":"Why do night photos of traffic show glowing streaks instead of cars?"},{"id":"lost-packet-resend","t":"machines","q":"Why does your computer quietly resend a packet that never arrives?"},{"id":"machine-code","t":"machines","q":"Why can a CPU only follow instructions written as plain numbers?"},{"id":"machine-learning-vs-rules","t":"machines","q":"Why is 'machine learning' different from a computer just following a list of instructions?"},{"id":"magnet-all-metals-myth","t":"machines","q":"Why won't a magnet pick up a coin or a scrunched-up ball of aluminium foil?"},{"id":"magnet-drop-weakens","t":"machines","q":"Why does dropping a magnet on the floor make it a little weaker each time?"},{"id":"magnet-field-through-paper","t":"machines","q":"Why can a magnet pull a paperclip through a sheet of paper without touching it?"},{"id":"magnet-fridge-door-not-magnet","t":"machines","q":"Why does a magnet stick to the fridge door if the door isn't a magnet itself?"},{"id":"magnet-healing-bracelet-myth","t":"machines","q":"Why do magnetic bracelets and insoles not actually help sore joints?"},{"id":"magnet-heat-loses-power","t":"machines","q":"Why does heating a magnet up make it stop working?"},{"id":"magnet-magnetometer-phone-compass","t":"machines","q":"Why can a smartphone show a working compass with no spinning needle inside it at all?"},{"id":"magnet-nail-domains-align","t":"machines","q":"Why does stroking a steel nail with a magnet turn the nail into a magnet too?"},{"id":"magnet-old-tv-colours","t":"machines","q":"Why could holding a strong magnet near an old TV scramble its colours?"},{"id":"magnet-shield-mu-metal","t":"machines","q":"Why can't you block a magnetic field with an ordinary wall or a wooden box?"},{"id":"magnet-strength-distance-drop","t":"machines","q":"Why does a magnet's pull fade so quickly as you move it just a little further away?"},{"id":"magnet-thick-steel-stronger-stick","t":"machines","q":"Why does a magnet stick more firmly to a thick steel door than to a thin sheet of the same metal?"},{"id":"magnet-through-table-trick","t":"machines","q":"Why can you drag a paperclip across a wooden table just by moving a hidden magnet underneath?"},{"id":"magnet-toy-cant-hover-still","t":"machines","q":"Why can't you balance two magnets in mid-air, one hovering perfectly still above the other?"},{"id":"magnetic-brake-eddy-current-coaster","t":"machines","q":"Why do some roller coasters slow down using magnets instead of ordinary brake pads?"},{"id":"magnetic-field-lines-filings","t":"machines","q":"Why do iron filings sprinkled near a magnet arrange themselves into neat curved lines?"},{"id":"magnetic-north-not-true-north","t":"machines","q":"Why isn't the north a compass points to exactly the same place as the North Pole on a map?"},{"id":"magnetic-tape-erase","t":"machines","q":"Why could holding a strong magnet near an old cassette tape wipe the music off it?"},{"id":"magnetic-window-cleaner","t":"machines","q":"Why can two magnets clean both sides of a window glass at the same time?"},{"id":"magnets-push","t":"machines","q":"Why do magnets push each other away?"},{"id":"magnifying-glass-fire","t":"machines","q":"Why can a magnifying glass start a fire?"},{"id":"magnifying-glass-how","t":"machines","q":"Why does a magnifying glass make things look bigger?"},{"id":"magnifying-glass-upside-down","t":"machines","q":"Why does a magnifying glass sometimes flip the picture upside down?"},{"id":"many-languages","t":"machines","q":"Why are there hundreds of different programming languages?"},{"id":"matte-anti-glare-screen","t":"machines","q":"Why do some monitors have a matte, slightly rough surface instead of shiny glass?"},{"id":"megaphone-cone-mechanism","t":"machines","q":"Why does a cone-shaped megaphone make your voice carry further?"},{"id":"microphone-reverse-speaker","t":"machines","q":"Why is a microphone basically a speaker running backwards?"},{"id":"microscope-magnify","t":"machines","q":"Why does a microscope use two lenses instead of just one?"},{"id":"microwave-heats","t":"machines","q":"Why does a microwave heat food?"},{"id":"mirror-silver-backing","t":"machines","q":"Why is a mirror a sheet of glass, when glass barely reflects anything?"},{"id":"mirrors-flip","t":"machines","q":"Why do mirrors flip left and right but not up and down?"},{"id":"mobile-data-towers","t":"machines","q":"Why does your phone need to talk to a tower on a hill instead of a router?"},{"id":"modem-vs-router","t":"machines","q":"Why do you need both a modem and a router, when they look like the same box?"},{"id":"moon-tiny-photo","t":"machines","q":"Why does the Moon look huge to your eyes but tiny in an ordinary photo?"},{"id":"moravec-paradox","t":"machines","q":"Why can a robot lift a car engine but not tie a shoelace?"},{"id":"more-pixels-stop-mattering","t":"machines","q":"Why does adding more pixels to a screen eventually stop making any visible difference?"},{"id":"motion-smoothing-soap-opera","t":"machines","q":"Why does switching on a TV's 'motion smoothing' make a film look like a home video?"},{"id":"mouse-cursor","t":"machines","q":"Why does moving your mouse move the arrow on the screen?"},{"id":"mri-machine-strong-magnet","t":"machines","q":"Why does an MRI scanner need such an incredibly strong magnet?"},{"id":"mri-remove-metal-safety","t":"machines","q":"Why do hospitals insist you remove every scrap of metal before an MRI scan?"},{"id":"multiple-lenses","t":"machines","q":"Why do phones now have three or four camera lenses instead of just one?"},{"id":"multitasking","t":"machines","q":"Why can a computer run lots of programs 'at the same time' on just one processor?"},{"id":"neodymium-magnet-strength","t":"machines","q":"Why is a small neodymium magnet so much stronger than an old fridge magnet the same size?"},{"id":"neodymium-magnet-swallow-danger","t":"machines","q":"Why are small, strong magnets dangerous if more than one gets swallowed?"},{"id":"neural-network-not-brain","t":"machines","q":"Why are a computer's 'neural networks' not actually copies of a real brain?"},{"id":"new-fairy-lights-survive","t":"machines","q":"Why do modern fairy lights keep working even if one bulb blows?"},{"id":"night-mode-photo","t":"machines","q":"Why can a phone photo of a dark room look brighter than the room looked to your own eyes?"},{"id":"no-one-owns-internet","t":"machines","q":"Why does no single company or government own the internet?"},{"id":"noise-cancelling-antiwave","t":"machines","q":"Why do noise-cancelling headphones make engine rumble disappear?"},{"id":"north-seeking-name-origin","t":"machines","q":"Why is the north end of a magnet called 'north-seeking' instead of just 'north'?"},{"id":"number-portability","t":"machines","q":"Why does your phone number follow you when you switch to a brand-new phone?"},{"id":"octane-rating-knocking","t":"machines","q":"Why do some petrol pumps offer fuel with a higher number, and does it really give a car more power?"},{"id":"oil-viscosity-numbers","t":"machines","q":"Why do bottles of engine oil have codes like '5W-30' printed on them?"},{"id":"old-fairy-lights-all-die","t":"machines","q":"Why did one blown bulb kill an entire string of old Christmas lights?"},{"id":"old-fuse-wire-replace","t":"machines","q":"Why did old fuse boxes need a wire replaced, while new ones just flick back on?"},{"id":"old-lcd-yellow-tinge","t":"machines","q":"Why did old LCD screens look slightly yellower than new ones?"},{"id":"old-resistive-touchscreen-stylus","t":"machines","q":"Why did some very old touchscreens need a hard plastic stylus instead of a fingertip?"},{"id":"old-tv-fishbowl-bulge","t":"machines","q":"Why did old TVs bulge out the back like a fishbowl?"},{"id":"old-tv-scan-power-grid","t":"machines","q":"Why did old TVs redraw their picture exactly 50 or 60 times a second?"},{"id":"oled-green-red-blue-dots","t":"machines","q":"Why do OLED screens pack in more green and red dots than blue ones?"},{"id":"oled-power-content","t":"machines","q":"Why does an OLED screen use less battery showing a photo of space than a photo of snow?"},{"id":"oled-true-black","t":"machines","q":"Why can an OLED screen make a truly black pixel that an LCD never can?"},{"id":"one-way-mirror","t":"machines","q":"Why can someone see through a one-way mirror from only one side?"},{"id":"os-need","t":"machines","q":"Why can't a computer do anything at all without an operating system?"},{"id":"packets-broken-up","t":"machines","q":"Why is a message broken into thousands of tiny packets before it's sent?"},{"id":"packets-different-routes","t":"machines","q":"Why can two packets from the same message travel completely different paths?"},{"id":"packets-out-of-order","t":"machines","q":"Why do packets get a number stamped on them before they leave?"},{"id":"panorama-stitch","t":"machines","q":"Why can a phone glue dozens of photos into one giant seamless picture?"},{"id":"paper-plane-fold","t":"machines","q":"Why does a paper aeroplane nosedive or spiral if the folds aren't even?"},{"id":"paperclip-chain-magnet","t":"machines","q":"Why can you hang a whole chain of paperclips from a single magnet, one dangling below another?"},{"id":"passwords","t":"machines","q":"Why do we need passwords?"},{"id":"periscope-mirrors","t":"machines","q":"Why can a submarine crew see the surface without poking their heads out of the water?"},{"id":"petrol-car-multi-gears","t":"machines","q":"Why does a petrol car need several gears to drive at different speeds?"},{"id":"phone-auto-brighten-outside","t":"machines","q":"Why do some phones get brighter by themselves the moment you walk outside?"},{"id":"phone-hot","t":"machines","q":"Why does my iPad get hot?"},{"id":"phone-screen-vanish-sunlight","t":"machines","q":"Why does a phone screen seem to vanish in bright sunlight?"},{"id":"phone-vibrate-motor","t":"machines","q":"Why can a flat phone with no visible motor shake itself so hard?"},{"id":"photo-metadata-location","t":"machines","q":"Why can a photo secretly reveal exactly where and when it was taken?"},{"id":"photo-zoom-squares","t":"machines","q":"Why does zooming into a photo eventually show giant coloured squares?"},{"id":"photobooth-strip","t":"machines","q":"Why does an old-style photo booth take a few minutes to hand you your strip?"},{"id":"ping-gaming","t":"machines","q":"Why do gamers panic about a high ping when playing people overseas?"},{"id":"pinhole-sharp-dim","t":"machines","q":"Why does a smaller pinhole make a sharper but darker picture?"},{"id":"plane-no-signal","t":"machines","q":"Why wouldn't your phone find a mobile signal at cruising height, even if you forgot to switch it off?"},{"id":"plane-window-rounded","t":"machines","q":"Why do plane windows have rounded corners instead of square ones?"},{"id":"planes-fly","t":"machines","q":"Why do planes stay up?"},{"id":"planes-struck-by-lightning","t":"machines","q":"Why doesn't a plane get seriously damaged when lightning strikes it mid-flight?"},{"id":"plug-third-pin","t":"machines","q":"Why does a three-pin plug have a third pin longer than the other two?"},{"id":"polarised-sunglasses-screen-black","t":"machines","q":"Why can polarised sunglasses turn a phone screen almost black?"},{"id":"polarizing-filter-sky","t":"machines","q":"Why can a filter make a photographed sky look deep blue instead of pale?"},{"id":"polaroid-develop","t":"machines","q":"Why does a Polaroid picture appear before your eyes?"},{"id":"portrait-mode-blur","t":"machines","q":"Why can a phone blur the background behind a face while keeping the face perfectly sharp?"},{"id":"power-steering-assist","t":"machines","q":"Why is it so easy to turn a heavy car's steering wheel with one finger?"},{"id":"power-strip-own-switch","t":"machines","q":"Why do power strips have their own on/off switch built in?"},{"id":"printer-cant-match-screen","t":"machines","q":"Why can't a printer ever match the bright colours you see glowing on a screen?"},{"id":"prism-rainbow-split","t":"machines","q":"Why does a glass prism split white light into a rainbow?"},{"id":"projector-colour-wheel","t":"machines","q":"Why do some projectors flash red, green and blue light too fast for you to notice?"},{"id":"projector-dark-room","t":"machines","q":"Why do projectors need a dark room to show a clear picture?"},{"id":"projector-image-dimmer-bigger","t":"machines","q":"Why does a projected picture get dimmer the bigger you stretch it?"},{"id":"propeller-planes-slower","t":"machines","q":"Why don't propeller planes fly nearly as fast as jets?"},{"id":"propeller-twisted-blade","t":"machines","q":"Why is a propeller blade twisted along its length instead of flat like a fan?"},{"id":"quantum-cold","t":"machines","q":"Why do some quantum computers need to be colder than outer space?"},{"id":"quantum-not-just-faster","t":"machines","q":"Why isn't a quantum computer just a much faster ordinary computer?"},{"id":"qwerty-keyboard","t":"machines","q":"Why aren't keyboard keys arranged in alphabetical order?"},{"id":"rack-and-pinion-steering","t":"machines","q":"Why does turning a round steering wheel make a car's wheels point left and right?"},{"id":"radar-nose-cone","t":"machines","q":"Why does a plane's pointed nose hide equipment rather than just being solid metal?"},{"id":"radiator-engine-cooling","t":"machines","q":"Why does a car engine need a radiator full of water at the front?"},{"id":"ram-forgets","t":"machines","q":"Why does RAM forget everything the instant the power goes off?"},{"id":"ram-vs-storage","t":"machines","q":"Why does a computer need both memory and storage?"},{"id":"raw-vs-jpeg","t":"machines","q":"Why do serious photographers shoot in 'RAW' instead of an ordinary photo file?"},{"id":"record-player-groove","t":"machines","q":"Why can a needle dragged through a groove on a spinning disc play music?"},{"id":"recycling-magnet-sort-steel","t":"machines","q":"Why do recycling centres run rubbish past giant magnets on a conveyor belt?"},{"id":"red-eye-flash","t":"machines","q":"Why do people's eyes glow red in flash photos?"},{"id":"red-vs-green-laser-pointer","t":"machines","q":"Why does a green laser pointer look brighter than a red one of the same power?"},{"id":"regenerative-braking","t":"machines","q":"Why do electric cars slow down partly just by lifting your foot off the accelerator?"},{"id":"restart-fixes","t":"machines","q":"Why does turning a computer off and on again fix so many problems?"},{"id":"robot-arm-rigid-adaptable","t":"machines","q":"Why can a factory robot repeat one task perfectly a million times but struggle with a slightly different one?"},{"id":"robot-dog-balance","t":"machines","q":"Why does a four-legged robot wobble and correct itself constantly instead of walking smoothly?"},{"id":"robot-find-charger","t":"machines","q":"Why can some robots find their own way back to a charging point without being guided?"},{"id":"robot-joints-dof","t":"machines","q":"Why do robot arms have so many separate joints?"},{"id":"robot-lidar-sight","t":"machines","q":"Why can a robot 'see' a room using laser light instead of a camera?"},{"id":"robot-mower-wire","t":"machines","q":"Why does a robot lawnmower never mow past the edge of the yard, with no fence in sight?"},{"id":"robot-sensor-drift","t":"machines","q":"Why does a robot sometimes need recalibrating even though nothing seems broken?"},{"id":"robot-servo-precision","t":"machines","q":"Why can a robot arm stop in exactly the same spot, thousands of times in a row?"},{"id":"robot-slam-mapping","t":"machines","q":"Why can a robot build a map of a room it has never entered before?"},{"id":"robot-vacuum","t":"machines","q":"Why doesn't a robot vacuum fall down the stairs?"},{"id":"robot-wheels-vs-legs","t":"machines","q":"Why do some robots roll on wheels while others walk on legs?"},{"id":"robot-word-origin","t":"machines","q":"Why is a robot called a 'robot'?"},{"id":"robots-not-self-aware","t":"machines","q":"Why can't a robot just 'wake up' and become self-aware one day?"},{"id":"robots-only-do-trained-tasks","t":"machines","q":"Why can't a robot decide to do a job nobody ever programmed or trained it for?"},{"id":"rockets","t":"machines","q":"Why do rockets work in space if there's nothing to push against?"},{"id":"rolling-shutter-bend","t":"machines","q":"Why do spinning propellers look bent or wobbly in phone videos?"},{"id":"router-picks-path","t":"machines","q":"Why does a router have to decide which way to send every single packet?"},{"id":"rubber-shoes-lightning-myth","t":"machines","q":"Why don't rubber-soled shoes protect you from a lightning strike?"},{"id":"rudder-vs-control-wheel","t":"machines","q":"Why do pilots need foot pedals for a rudder as well as a control wheel?"},{"id":"runways-face-wind","t":"machines","q":"Why do runways usually point in a particular direction rather than any old way?"},{"id":"safety-switch-fast-trip","t":"machines","q":"Why can a safety switch cut the power in 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phone with no SIM card still connect to wifi but not make an ordinary call?"},{"id":"sim-secret-key","t":"machines","q":"Why does a SIM card need to hold a secret code hidden inside it?"},{"id":"site-slow-busy-server","t":"machines","q":"Why does a popular website slow to a crawl when everyone visits at once?"},{"id":"site-slow-server-far","t":"machines","q":"Why can the same website load faster for a friend overseas than for you?"},{"id":"slr-mirror-flip","t":"machines","q":"Why do some cameras have a mirror that flips out of the way with a loud clack?"},{"id":"smartphone-mic-tiny","t":"machines","q":"Why can a microphone smaller than a grain of rice fit inside a slim phone?"},{"id":"sms-160-limit","t":"machines","q":"Why were early text messages limited to exactly 160 characters?"},{"id":"soap-cleans","t":"machines","q":"Why does soap clean things?"},{"id":"socket-live-empty","t":"machines","q":"Why is a wall socket still live even with nothing plugged into it?"},{"id":"software-slows-phone","t":"machines","q":"Why can a phone feel sluggish after a software update, even though nothing inside it changed?"},{"id":"sonic-boom-mechanism","t":"machines","q":"Why does a jet flying faster than sound produce a sudden loud boom?"},{"id":"sound-no-vacuum","t":"machines","q":"Why can't sound travel through the vacuum of space?"},{"id":"spark-plug-timing","t":"machines","q":"Why does the spark inside an engine fire before the piston reaches the top?"},{"id":"spark-when-unplugging","t":"machines","q":"Why can you sometimes see a tiny spark when unplugging something that's switched on?"},{"id":"speaker-cone-not-vibrating-electricity","t":"machines","q":"Why is it wrong to say a speaker turns electricity into sound by vibrating the electricity itself?"},{"id":"speaker-mesh-water","t":"machines","q":"Why can sound escape a sealed phone speaker without water getting in?"},{"id":"speakers","t":"machines","q":"Why does a speaker make 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weakens?"},{"id":"stylus-rubber-tip-pencil","t":"machines","q":"Why does a soft rubber-tipped stylus work on a touchscreen but a wooden pencil doesn't?"},{"id":"sunglasses-uv-protection","t":"machines","q":"Why can dark sunglasses let in more sun damage than none at all?"},{"id":"supercharger-belt-driven","t":"machines","q":"Why do some engines use a supercharger instead of a turbocharger?"},{"id":"swept-wings-jets","t":"machines","q":"Why do fast jets have wings angled backward instead of sticking straight out?"},{"id":"switch-breaks-one-wire","t":"machines","q":"Why does a light switch only need to interrupt one of the two wires, not both?"},{"id":"takeoff-vs-landing-distance","t":"machines","q":"Why does a plane usually need a longer runway to take off than to land?"},{"id":"telephoto-compress","t":"machines","q":"Why do zoomed-in photos make faraway things look squashed close together?"},{"id":"telescope-lens-vs-mirror","t":"machines","q":"Why do the biggest telescopes use mirrors 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cool?"},{"id":"too-many-tabs","t":"machines","q":"Why does opening lots of browser tabs slow everything else down?"},{"id":"torque-vs-horsepower","t":"machines","q":"Why do car adverts talk about both 'torque' and 'horsepower' as if they're different things?"},{"id":"touchscreen","t":"machines","q":"Why does a touchscreen know my finger?"},{"id":"touchscreen-glass","t":"machines","q":"Why are phone screens made of glass instead of plastic?"},{"id":"tower-handover","t":"machines","q":"Why doesn't a phone call cut out the moment you drive from one tower's patch into the next?"},{"id":"traction-control-wheelspin","t":"machines","q":"Why can a car's engine cut power on its own when a wheel spins on ice?"},{"id":"transistor-switch","t":"machines","q":"Why can a transistor switch on and off with nothing inside it moving?"},{"id":"translation-app-idioms","t":"machines","q":"Why do translation apps still get jokes and sayings wrong?"},{"id":"tunnel-signal","t":"machines","q":"Why does your phone signal vanish the instant you drive into a tunnel?"},{"id":"turbo-exhaust-reuse","t":"machines","q":"Why does a turbocharger make an engine stronger without burning extra fuel?"},{"id":"turbo-lag","t":"machines","q":"Why does a turbocharged car sometimes feel slow to respond, then suddenly surge?"},{"id":"turbulence-not-dangerous","t":"machines","q":"Why doesn't turbulence actually damage the plane, even when it feels scary?"},{"id":"turing-test-limits","t":"machines","q":"Why can it be so hard to tell whether you're chatting with a person or a computer online?"},{"id":"tv-local-dimming","t":"machines","q":"Why can a TV dim just one corner of the screen during a dark movie scene?"},{"id":"two-wires-more-dangerous","t":"machines","q":"Why is it far more dangerous to touch two power lines at once than just one?"},{"id":"tyre-contact-patch","t":"machines","q":"Why does a tyre's shape do more for grip than the fact that it's round?"},{"id":"tyre-pressure-grip","t":"machines","q":"Why does a slightly flat tyre wear out faster and use more fuel?"},{"id":"tyre-tread-water-channels","t":"machines","q":"Why do tyres have grooves cut into them instead of being smooth?"},{"id":"tyres-dont-burst-landing","t":"machines","q":"Why don't a plane's tyres burst from the shock of landing at high speed?"},{"id":"ultrasonic-dog-whistle","t":"machines","q":"Why can a dog whistle make a sound your dog hears but you can't?"},{"id":"ultrasonic-fingerprint","t":"machines","q":"Why can some phones read your fingerprint straight through the glass screen?"},{"id":"undersea-cable-breaks","t":"machines","q":"Why do undersea cables break more often from ships' anchors than from sharks?"},{"id":"undersea-cable-repair","t":"machines","q":"Why can it take weeks to fix one broken undersea cable?"},{"id":"undersea-cable-thin","t":"machines","q":"Why is a cable carrying a whole country's internet no fatter than a garden hose?"},{"id":"undersea-cables-carry-internet","t":"machines","q":"Why does almost all the internet between continents travel through cables on the seafloor?"},{"id":"underwater-blue-photos","t":"machines","q":"Why do underwater photos often lose their red colours?"},{"id":"vacuum-tube-heat","t":"machines","q":"Why did the earliest computers need their valves replaced constantly?"},{"id":"van-de-graaff-hair","t":"machines","q":"Why does touching a Van de Graaff generator make your hair stand up?"},{"id":"vibration-patterns","t":"machines","q":"Why can you tell a call from a text just by feeling how your phone buzzes?"},{"id":"voice-assistant-mishear","t":"machines","q":"Why does a voice assistant sometimes mishear a simple, clearly spoken word?"},{"id":"vr-headset-refresh-rate","t":"machines","q":"Why does a VR headset need a much faster refresh rate than an ordinary screen?"},{"id":"vr-lens-close-screen-far","t":"machines","q":"Why can a screen just centimetres from your eyeball look far away in a VR headset?"},{"id":"vr-no-glasses-needed","t":"machines","q":"Why doesn't a VR headset need you to wear glasses, the way a 3D movie does?"},{"id":"vr-two-different-pictures","t":"machines","q":"Why does a VR headset show your eyes two slightly different pictures?"},{"id":"vtol-vs-runway","t":"machines","q":"Why can't most planes simply take off straight up like a helicopter?"},{"id":"warehouse-robot-grid","t":"machines","q":"Why do warehouse robots follow a grid of markers stuck to the floor?"},{"id":"waterproof-seals-wear","t":"machines","q":"Why can a phone that once survived a swim stop being waterproof a year later?"},{"id":"web-vs-internet","t":"machines","q":"Why are the web and the internet not actually the same thing?"},{"id":"wet-ground-more-dangerous","t":"machines","q":"Why is touching a faulty appliance more dangerous when you're standing on wet ground?"},{"id":"why-active-vs-passive-speaker","t":"machines","q":"Why do some speakers need a power cable while others just plug 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a siren sound higher as it nears you and lower once it passes?"},{"id":"why-sound-fades-distance","t":"machines","q":"Why does a sound get quieter the further away you stand from it?"},{"id":"why-speaker-wire-thickness","t":"machines","q":"Why do some speaker cables look thicker than ordinary wire?"},{"id":"why-string-instrument-body-hollow","t":"machines","q":"Why is a guitar body hollow instead of solid wood all the way through?"},{"id":"why-thunder-rumbles-not-crack","t":"machines","q":"Why does thunder rumble on for seconds instead of one sharp crack?"},{"id":"why-tuning-fork-single-note","t":"machines","q":"Why does a tuning fork always ring out the exact same clean note?"},{"id":"why-vinyl-hiss-and-crackle","t":"machines","q":"Why do old vinyl records crackle even during quiet parts of a song?"},{"id":"why-voices-sound-different","t":"machines","q":"Why does everyone's voice sound different saying the exact same word?"},{"id":"wifi-vs-mobile-data","t":"machines","q":"Why are WiFi 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it?"},{"id":"zip-shut","t":"machines","q":"Why does a zip stay shut?"},{"id":"zip-smaller","t":"machines","q":"Why does zipping a file make it smaller?"},{"id":"acid-rain-stone","t":"earth","q":"Why can acid rain dissolve stone statues?"},{"id":"afternoon-storm-clockwork","t":"earth","q":"Why do many tropical places get a storm every afternoon like clockwork?"},{"id":"amazon-flying-rivers","t":"earth","q":"Why can the Amazon rainforest make its own rain?"},{"id":"analemma-figure8","t":"earth","q":"Why does the Sun trace a figure-eight if you photograph it at the same clock time all year?"},{"id":"ancient-day-length-fossil","t":"earth","q":"Why do fossil corals suggest a year once had 400 days in it?"},{"id":"animals-predict-earthquakes-myth","t":"earth","q":"Why can't scientists confirm that animals really sense earthquakes before they happen?"},{"id":"antarctica-desert","t":"earth","q":"Why is Antarctica actually classified as a desert?"},{"id":"anticrepuscular-rays","t":"earth","q":"Why can shadow-rays seem to meet opposite the setting Sun?"},{"id":"arctic-vs-antarctic","t":"earth","q":"Why does the Arctic float on the ocean while Antarctica sits on solid land?"},{"id":"atacama-coastal-desert","t":"earth","q":"Why is one of the world's driest deserts sitting right next to the ocean?"},{"id":"atomic-clock-second","t":"earth","q":"Why is the length of a second no longer measured by Earth's spin?"},{"id":"australia-wet-dry","t":"earth","q":"Why do parts of northern Australia have just two seasons, the wet and the dry?"},{"id":"avalanche-air-blast","t":"earth","q":"Why can an avalanche knock down trees before any snow has actually reached them?"},{"id":"avalanche-airbag-float","t":"earth","q":"Why does pulling a cord on a backpack help a buried skier float near the surface?"},{"id":"avalanche-cause","t":"earth","q":"Why do avalanches suddenly let go all at once?"},{"id":"avalanche-control","t":"earth","q":"Why do ski patrols set off small avalanches on purpose?"},{"id":"avalanche-debris-concrete","t":"earth","q":"Why can avalanche snow set almost like concrete the moment it stops moving?"},{"id":"avalanche-dog-scent","t":"earth","q":"Why can a trained dog smell a buried skier through metres of snow?"},{"id":"avalanche-powder-fluid","t":"earth","q":"Why can a powder avalanche move faster than a car on a motorway?"},{"id":"avalanche-slab-loose","t":"earth","q":"Why do some avalanches slide as one huge sheet while others start from a single point?"},{"id":"avalanche-trigger","t":"earth","q":"Why can one skier trigger an avalanche a whole slope of snow was holding back?"},{"id":"avalanche-wet","t":"earth","q":"Why can warm weather cause an avalanche without any fresh snow falling?"},{"id":"ball-lightning-mystery","t":"earth","q":"Why is ball lightning still one of science's great unsolved puzzles?"},{"id":"banner-clouds","t":"earth","q":"Why does a flag of cloud stream off one side of a mountain peak?"},{"id":"basalt-vs-granite-volcanic-rock","t":"earth","q":"Why is most ocean floor rock dark and fine-grained while mountain granite is pale and speckled?"},{"id":"base-isolation-buildings","t":"earth","q":"Why do some important buildings sit on giant rubber pads instead of directly on the ground?"},{"id":"bathtub-coriolis-myth","t":"earth","q":"Why doesn't your bath actually drain a different way depending on your hemisphere?"},{"id":"black-ice","t":"earth","q":"Why is black ice so hard to see on a road?"},{"id":"blizzard-ground","t":"earth","q":"Why can a blizzard rage on a clear day with no snow falling from the sky?"},{"id":"boiling-water-instant-snow","t":"earth","q":"Why can throwing a cup of boiling water into freezing air make it vanish into a puff of ice fog?"},{"id":"brocken-spectre","t":"earth","q":"Why can your own shadow on a misty hilltop look like a giant figure?"},{"id":"building-sink-liquefaction","t":"earth","q":"Why can a building sink into the ground during an earthquake even without any visible cracks?"},{"id":"buildings-sway-earthquake","t":"earth","q":"Why are modern skyscrapers designed to sway during an earthquake instead of staying rigid?"},{"id":"caldera-not-a-mountain","t":"earth","q":"Why can a volcano leave behind a giant hole in the ground instead of a mountain?"},{"id":"calendar-lunar-vs-solar","t":"earth","q":"Why does Lunar New Year fall on a different date every year while the 1st of January never moves?"},{"id":"candle-ice-lake","t":"earth","q":"Why can melting lake ice fall apart into a heap of icy pencils?"},{"id":"caves","t":"earth","q":"Why are there caves?"},{"id":"cd-rainbow","t":"earth","q":"Why does the shiny underside of a CD show swirling rainbow colours?"},{"id":"chile-1960-biggest-earthquake","t":"earth","q":"Why was the 1960 Chile earthquake so much more powerful than any other earthquake ever measured?"},{"id":"china-one-timezone","t":"earth","q":"Why does China run on just one time zone even though it's as wide as five?"},{"id":"circumzenithal-arc","t":"earth","q":"Why does an upside-down rainbow sometimes appear high overhead?"},{"id":"cirrus-warning","t":"earth","q":"Why do clouds arrive in a set order before a big storm?"},{"id":"clock-24-hour","t":"earth","q":"Why do some countries write times like 18:00 instead of 6 pm?"},{"id":"cloud-anvil-top","t":"earth","q":"Why do storm clouds spread out flat on top like an anvil?"},{"id":"cloud-base-rise","t":"earth","q":"Why do clouds start low in the morning and sit higher by afternoon?"},{"id":"cloud-cirrus","t":"earth","q":"Why are the highest clouds thin and wispy?"},{"id":"cloud-cover-cools-day","t":"earth","q":"Why do clouds make summer days cooler as well as winter nights milder?"},{"id":"cloud-cumulonimbus","t":"earth","q":"Why do storm clouds tower so high?"},{"id":"cloud-cumulus","t":"earth","q":"Why do cumulus clouds look like piles of cotton wool?"},{"id":"cloud-flat-bottoms","t":"earth","q":"Why do fluffy clouds have flat bottoms?"},{"id":"cloud-green-storm","t":"earth","q":"Why do some storm clouds look green?"},{"id":"cloud-height","t":"earth","q":"Why are some clouds much higher up than others?"},{"id":"cloud-iridescent","t":"earth","q":"Why do some clouds shine with patches of rainbow colour?"},{"id":"cloud-seeding","t":"earth","q":"Why do people fire chemicals into clouds to try to make it rain?"},{"id":"cloud-shadows","t":"earth","q":"Why can a cloud's shadow race across a hillside faster than the cloud seems to move?"},{"id":"cloud-shapes-animals","t":"earth","q":"Why do clouds sometimes look like animals or faces?"},{"id":"cloud-stand-on","t":"earth","q":"Why can't you stand on a cloud?"},{"id":"cloud-stratocumulus","t":"earth","q":"Why do clouds sometimes look like a tray of grey lumps covering the whole sky?"},{"id":"cloud-stratus","t":"earth","q":"Why does the sky sometimes turn into one flat grey sheet instead of fluffy clouds?"},{"id":"clouds-float","t":"earth","q":"Why do clouds float if they're full of water?"},{"id":"clouds-grey","t":"earth","q":"Why do clouds turn grey before it rains?"},{"id":"clouds-sunset-colour","t":"earth","q":"Why do clouds turn pink and orange at sunset?"},{"id":"clouds-vanish","t":"earth","q":"Why do clouds sometimes disappear right in front of you?"},{"id":"clouds-white","t":"earth","q":"Why are clouds white?"},{"id":"cloudy-nights-warmer","t":"earth","q":"Why are cloudy nights often warmer than clear ones?"},{"id":"compass-north","t":"earth","q":"Why does a compass point north?"},{"id":"continents-move","t":"earth","q":"Why do the continents move?"},{"id":"contrail-climate","t":"earth","q":"Why do scientists worry that aeroplane contrails might warm the planet?"},{"id":"contrails-form","t":"earth","q":"Why do aeroplanes leave white trails across the sky?"},{"id":"contrails-persist","t":"earth","q":"Why do some plane trails spread into a hazy sheet of cloud?"},{"id":"corn-snow-spring","t":"earth","q":"Why do spring skiers wait for snow to turn into \"corn\"?"},{"id":"corona-ring","t":"earth","q":"Why can a tight coloured ring appear right around the Sun or Moon?"},{"id":"crepuscular-rays","t":"earth","q":"Why do sunbeams through cloud gaps look like they're fanning out?"},{"id":"cryoconite-holes-glacier","t":"earth","q":"Why does melting glacier ice sometimes have small, muddy cylinders drilled straight into it?"},{"id":"cumulus-grow-storm","t":"earth","q":"Why can a small fluffy cloud turn into a thunderstorm within an hour?"},{"id":"cyclone-equator-gap","t":"earth","q":"Why can't a cyclone form right on the equator?"},{"id":"cyclone-eyewall-winds","t":"earth","q":"Why are a cyclone's fiercest winds found in a ring, not in the centre?"},{"id":"cyclone-names","t":"earth","q":"Why is a hurricane, a cyclone and a typhoon the same kind of storm?"},{"id":"cyclone-warm-water","t":"earth","q":"Why do cyclones only form over warm tropical ocean water?"},{"id":"cyclone-weaken-land","t":"earth","q":"Why does a cyclone weaken so fast once it crosses onto land?"},{"id":"date-line-yesterday-tomorrow","t":"earth","q":"Why can stepping across one line in the Pacific Ocean land you a whole day away?"},{"id":"date-line-zigzag","t":"earth","q":"Why does the International Date Line swerve instead of running straight down the map?"},{"id":"day-night-rotation","t":"earth","q":"Why does Earth have day and night?"},{"id":"daylight-saving-equator-skip","t":"earth","q":"Why do countries near the equator not bother with daylight saving?"},{"id":"daylight-saving-shift","t":"earth","q":"Why do clocks jump forward and back twice a year?"},{"id":"days-getting-longer","t":"earth","q":"Why are Earth's days slowly getting longer?"},{"id":"deserts","t":"earth","q":"Why are deserts dry?"},{"id":"dew","t":"earth","q":"Why is the grass wet in the morning if it hasn't rained?"},{"id":"dewdrop-lens","t":"earth","q":"Why can a dewdrop on a leaf act like a tiny magnifying glass?"},{"id":"diamond-dust","t":"earth","q":"Why can the air itself sparkle with \"diamond dust\" in bitter cold?"},{"id":"dormant-extinct-active","t":"earth","q":"Why do volcanologists insist on three different words — active, dormant and extinct — instead of just calling every quiet volcano \"dead\"?"},{"id":"downpour-rate","t":"earth","q":"Why can a storm dump more rain in ten minutes than a drizzly day manages in ten hours?"},{"id":"drizzle-mist-feel","t":"earth","q":"Why does light rain feel like mist while heavy rain stings?"},{"id":"drought-hard-soil-flood","t":"earth","q":"Why does a drought make the next storm's flooding worse?"},{"id":"drought-usual-rain-place","t":"earth","q":"Why can a drought happen in a place that usually gets plenty of rain?"},{"id":"dune-ripples","t":"earth","q":"Why does sand have ripples in it?"},{"id":"earth-middle-hot","t":"earth","q":"Why is the middle of the Earth so hot?"},{"id":"earth-spin-origin","t":"earth","q":"Why does the Earth spin at all?"},{"id":"earth-warming","t":"earth","q":"Why is the Earth getting warmer?"},{"id":"earthquake-aftershocks","t":"earth","q":"Why do earthquakes keep happening for weeks after the big one?"},{"id":"earthquake-depth-shallow-deep","t":"earth","q":"Why can a deep earthquake feel weaker than a shallow one of the exact same size?"},{"id":"earthquake-duration-seconds","t":"earth","q":"Why does the ground only shake for a few seconds even in a huge earthquake?"},{"id":"earthquake-early-warning-seconds","t":"earth","q":"Why can phones warn people about an earthquake seconds before the shaking actually arrives?"},{"id":"earthquake-foreshock-hindsight","t":"earth","q":"Why can't scientists tell a small earthquake is a warning sign until after the big one hits?"},{"id":"earthquake-light-mystery","t":"earth","q":"Why do some earthquakes come with strange flashes of light in the sky that scientists still can't fully explain?"},{"id":"earthquake-magnitude-logarithmic","t":"earth","q":"Why does one extra number on the earthquake magnitude scale mean so much more shaking?"},{"id":"earthquake-prediction-impossible","t":"earth","q":"Why can't scientists predict exactly when the next big earthquake will hit?"},{"id":"earthquake-same-magnitude-different-damage","t":"earth","q":"Why can two earthquakes of exactly the same size cause wildly different amounts of damage?"},{"id":"earthquake-shaking-distant-buildings-resonance","t":"earth","q":"Why did some tall buildings in Mexico City sway badly during a quake centred hundreds of kilometres away?"},{"id":"earthquake-swarms","t":"earth","q":"Why do some places get dozens of similar-sized earthquakes in a row instead of one big one?"},{"id":"earthquake-triggered-landslides","t":"earth","q":"Why do earthquakes cause landslides on slopes far from where the ground actually broke?"},{"id":"earthquake-weather-myth","t":"earth","q":"Why is there no such thing as earthquake weather?"},{"id":"earthquakes","t":"earth","q":"Why do earthquakes happen?"},{"id":"epicentre-vs-focus","t":"earth","q":"Why is the epicentre not actually the place where an earthquake starts?"},{"id":"equation-of-time","t":"earth","q":"Why can a sundial run up to sixteen minutes \"wrong\" compared to a clock?"},{"id":"eruption-types-explosive-effusive","t":"earth","q":"Why do some volcanoes ooze quietly while others explode?"},{"id":"extinct-volcano-new-zealand-auckland","t":"earth","q":"Why is a major modern city sometimes built right across a whole field of extinct volcanoes?"},{"id":"farmers-rain-timing","t":"earth","q":"Why do farmers care about when rain falls, not just how much?"},{"id":"fault-creep-vs-stick-slip","t":"earth","q":"Why do some faults slide smoothly all the time while nearby faults suddenly jerk in violent earthquakes?"},{"id":"fissure-vent-no-mountain","t":"earth","q":"Why can lava pour out of a straight crack in the ground with no mountain in sight?"},{"id":"flash-flood-dry-riverbed","t":"earth","q":"Why can a dry riverbed suddenly fill with a wall of water?"},{"id":"flood-city-vs-forest","t":"earth","q":"Why can heavy rain flood a city street but barely dampen a forest?"},{"id":"flying-above-clouds","t":"earth","q":"Why do clouds look like a snowy floor when you fly above them?"},{"id":"foehn-wind","t":"earth","q":"Why is it warm and dry on one side of a mountain range and wet on the other?"},{"id":"fog","t":"earth","q":"Why is there fog some mornings?"},{"id":"fogbow","t":"earth","q":"Why does a fogbow look pale white instead of colourful like a rainbow?"},{"id":"footpath-snow-turns-ice","t":"earth","q":"Why does snow trampled flat on a footpath turn to solid, slippery ice within a day or two?"},{"id":"fossils","t":"earth","q":"Why do fossils exist?"},{"id":"franklin-kite","t":"earth","q":"Why didn't Benjamin Franklin's famous kite experiment kill him?"},{"id":"freezing-rain-glaze","t":"earth","q":"Why does freezing rain coat everything in a smooth sheet of ice while sleet just bounces off?"},{"id":"frost-patterns","t":"earth","q":"Why does frost make patterns on the window?"},{"id":"frost-radiative-grass","t":"earth","q":"Why can frost coat the grass on a morning the weather forecast never said would drop below freezing?"},{"id":"frosted-glass-blur","t":"earth","q":"Why does looking through frosted glass blur everything behind it?"},{"id":"geyser-hot-spring-volcanic","t":"earth","q":"Why does a geyser blast boiling water into the air on a timer, instead of just steaming quietly like a hot spring?"},{"id":"glacier-blue-ice","t":"earth","q":"Why does glacier ice sometimes glow deep blue?"},{"id":"glacier-calving-boom","t":"earth","q":"Why do glaciers suddenly break off giant chunks of ice into the sea?"},{"id":"glacier-crevasses","t":"earth","q":"Why do deep cracks called crevasses open across a glacier?"},{"id":"glacier-fed-river","t":"earth","q":"Why do glacier-fed rivers keep flowing even in the depths of winter?"},{"id":"glacier-flow","t":"earth","q":"Why do glaciers slide downhill even though they are solid ice?"},{"id":"glacier-surge-speedup","t":"earth","q":"Why can a glacier suddenly start moving 100 times faster than normal?"},{"id":"glacier-u-valley","t":"earth","q":"Why do glaciers carve valleys shaped like a U instead of a V?"},{"id":"glass-sweat","t":"earth","q":"Why does a cold glass of juice \"sweat\" on a hot day?"},{"id":"glory","t":"earth","q":"Why can a ring of colour appear around a plane's shadow on the clouds below?"},{"id":"gravity-fall","t":"earth","q":"Why do things fall down?"},{"id":"green-flash","t":"earth","q":"Why does the Sun sometimes flash green just as it sets?"},{"id":"hail","t":"earth","q":"Why does it hail in summer?"},{"id":"hail-fall-speed","t":"earth","q":"Why doesn't a giant hailstone smash through a roof at deadly speed?"},{"id":"hail-graupel","t":"earth","q":"Why does snow sometimes fall as tiny soft pellets that bounce like polystyrene?"},{"id":"hail-onion-layers","t":"earth","q":"Why does a hailstone look like a sliced onion inside?"},{"id":"hail-radar-detect","t":"earth","q":"Why can weather forecasters warn a town about hail minutes before it actually falls?"},{"id":"hail-swath-strip","t":"earth","q":"Why does hail damage often land in one narrow strip of a town, leaving the street next to it untouched?"},{"id":"hail-updraft-strength","t":"earth","q":"Why does hail only grow to a dangerous size in the fiercest storms?"},{"id":"half-hour-timezone-offset","t":"earth","q":"Why do some countries set their clocks half an hour off their neighbours?"},{"id":"heat-lightning-myth","t":"earth","q":"Why does silent \"heat lightning\" have nothing to do with heat?"},{"id":"heat-shimmer","t":"earth","q":"Why does the air above a candle or hot barbecue look wavy and blurry?"},{"id":"heiligenschein","t":"earth","q":"Why can your shadow's head seem to glow with a halo on dewy grass?"},{"id":"horizon","t":"earth","q":"Why can't I see any further than the horizon?"},{"id":"hotspot-volcano-plate-moves","t":"earth","q":"Why does a single hotspot create a whole chain of volcanic islands instead of just one?"},{"id":"hour-twelve-origin","t":"earth","q":"Why does a clock face have twelve numbers instead of ten?"},{"id":"humid-feels-hotter","t":"earth","q":"Why do humid days feel hotter than dry days at the same temperature?"},{"id":"humidity-wood-swell","t":"earth","q":"Why do wooden doors stick on a humid day?"},{"id":"ice-core-drill","t":"earth","q":"Why do scientists drill down through kilometres of ice just to study air?"},{"id":"ice-core-layers","t":"earth","q":"Why do ice cores show stripes like the rings inside a tree?"},{"id":"ice-core-temperature","t":"earth","q":"Why can an ice core tell us how warm the planet was thousands of years ago?"},{"id":"ice-cube-crack-drink","t":"earth","q":"Why does an ice cube crack loudly the moment it hits a warm drink?"},{"id":"ice-slippery","t":"earth","q":"Why is ice slippery to walk on?"},{"id":"iceberg-flip","t":"earth","q":"Why do icebergs sometimes suddenly roll over?"},{"id":"iceberg-green","t":"earth","q":"Why are some icebergs green instead of white or blue?"},{"id":"iceberg-radar-danger","t":"earth","q":"Why are icebergs still dangerous to ships that carry radar?"},{"id":"iceberg-tip","t":"earth","q":"Why is only a small tip of an iceberg visible above the water?"},{"id":"icicle-form","t":"earth","q":"Why do icicles form in a melt-and-freeze cycle?"},{"id":"icicle-ridges","t":"earth","q":"Why do icicles grow rippled ridges instead of a smooth surface?"},{"id":"igloo-warm","t":"earth","q":"Why do igloos keep people warm when they're built out of snow?"},{"id":"induced-earthquakes-fracking","t":"earth","q":"Why can pumping water deep underground cause an earthquake in a place that rarely had them before?"},{"id":"jet-lag-timezones","t":"earth","q":"Why does flying across time zones leave you feeling awful for days?"},{"id":"julian-gregorian-jump","t":"earth","q":"Why did people in 1582 go to sleep on the 4th of October and wake up on the 15th?"},{"id":"jupiter-clouds","t":"earth","q":"Why does Jupiter have coloured stripy clouds?"},{"id":"jupiter-fast-day","t":"earth","q":"Why does giant Jupiter spin all the way around in under ten hours?"},{"id":"kettle-steam","t":"earth","q":"Why is the puff from a boiling kettle white, when steam is invisible?"},{"id":"krakatoa-sound","t":"earth","q":"Why was one volcanic eruption loud enough to be heard nearly 5,000 kilometres away?"},{"id":"lahar-volcanic-mudflow","t":"earth","q":"Why can a snow-capped volcano trigger a deadly flood even long after an eruption has finished?"},{"id":"lake-effect-snow-band","t":"earth","q":"Why can one town get buried under a metre of snow while a town nearby gets barely a dusting?"},{"id":"lake-freeze-top","t":"earth","q":"Why do lakes freeze from the top down instead of the bottom up?"},{"id":"lake-ice-booming","t":"earth","q":"Why do frozen lakes sometimes boom and crack like distant thunder?"},{"id":"lake-ice-white-weak","t":"earth","q":"Why do ice fishers trust clear ice far more than white, opaque ice of the same thickness?"},{"id":"lake-mirror-reflection","t":"earth","q":"Why can a still lake reflect the sky almost like a perfect mirror?"},{"id":"lava-flow-slow-not-always","t":"earth","q":"Why can you usually just walk away from a lava flow, even though it destroys everything it touches?"},{"id":"lava-tube-formation","t":"earth","q":"Why can a river of lava end up flowing invisibly, hidden inside a tunnel of its own making?"},{"id":"leap-day-february","t":"earth","q":"Why does the extra leap day always land in February?"},{"id":"leap-second","t":"earth","q":"Why do the world's clocks sometimes get an extra \"leap second\" tacked on?"},{"id":"leap-year-rule","t":"earth","q":"Why do leap years skip most century years, like 1900, but not 2000?"},{"id":"lenticular-clouds","t":"earth","q":"Why do some clouds look like flying saucers?"},{"id":"light-bends-in-water","t":"earth","q":"Why does light bend when it passes from air into water?"},{"id":"light-pillar","t":"earth","q":"Why can a glowing pillar of light stretch up from a rising or setting Sun?"},{"id":"lightning-bolt-from-blue","t":"earth","q":"Why can lightning strike from a clear patch of sky far from any rain?"},{"id":"lightning-branch-alive","t":"earth","q":"Why do only some branches of a lightning bolt actually reach the ground?"},{"id":"lightning-forks","t":"earth","q":"Why does lightning split into branches instead of one single line?"},{"id":"lightning-ground-current","t":"earth","q":"Why can lightning hurt someone it never directly touches?"},{"id":"lightning-rod-works","t":"earth","q":"Why does a metal rod on a roof protect a whole building?"},{"id":"lightning-stepped-leader","t":"earth","q":"Why does lightning seem to feel its way down in short, stuttering steps?"},{"id":"lightning-strikes-twice","t":"earth","q":"Why does lightning strike the same place twice, over and over?"},{"id":"lightning-tall","t":"earth","q":"Why does lightning hit tall things?"},{"id":"lightning-upward-strike","t":"earth","q":"Why does the bright flash you see actually travel upward, not down?"},{"id":"lightning-zigzag","t":"earth","q":"Why does lightning zigzag instead of dropping straight down?"},{"id":"liquefaction-sand","t":"earth","q":"Why can wet, sandy ground suddenly behave like a liquid during an earthquake?"},{"id":"mackerel-sky","t":"earth","q":"Why does a rippled, scaly-looking sky have sailors' rhymes written about it?"},{"id":"magma-forms-how","t":"earth","q":"Why does solid mantle rock ever turn into liquid magma at all?"},{"id":"magma-vs-lava","t":"earth","q":"Why do scientists insist magma and lava are different things?"},{"id":"mammatus-clouds","t":"earth","q":"Why do some clouds hang down in strange pouches?"},{"id":"mantle-solid-not-ocean","t":"earth","q":"Why is the mantle mostly solid rock instead of an ocean of molten lava?"},{"id":"mars-clouds","t":"earth","q":"Why does dry, dusty Mars still have clouds?"},{"id":"mars-day-length-2","t":"earth","q":"Why is a day on Mars nearly the same length as a day on Earth?"},{"id":"megacryometeor-mystery","t":"earth","q":"Why do huge chunks of ice sometimes fall from a completely clear sky?"},{"id":"megathrust-subduction-earthquake","t":"earth","q":"Why do the most powerful earthquakes on Earth happen where one plate dives beneath another?"},{"id":"megathrust-vs-short-fault-power","t":"earth","q":"Why can one earthquake be a hundred times more powerful than another even on a similar-looking fault map?"},{"id":"mercury-day-two-years","t":"earth","q":"Why does one sunrise-to-sunrise day on Mercury outlast two of its years?"},{"id":"minute-sixty","t":"earth","q":"Why do a minute and an hour both split into 60, not 100?"},{"id":"mirage-fata-morgana","t":"earth","q":"Why can ships sometimes appear to float in the air above the horizon?"},{"id":"mirage-road","t":"earth","q":"Why does a hot road look like it has puddles that vanish as you approach?"},{"id":"mirror-fog-shower","t":"earth","q":"Why does a bathroom mirror fog up after a hot shower?"},{"id":"mirror-left-right-flip","t":"earth","q":"Why does a mirror flip left and right, but never flip you upside down?"},{"id":"monsoon-flood-drought","t":"earth","q":"Why can the same monsoon flood one year and fail the next?"},{"id":"monsoon-wind-reverse","t":"earth","q":"Why does the wind reverse and bring months of rain to India each year?"},{"id":"moon-day-length","t":"earth","q":"Why does a \"day\" on the Moon last almost a month?"},{"id":"moon-halo","t":"earth","q":"Why is there sometimes a ring around the Moon?"},{"id":"moon-mars-volcanoes-dead","t":"earth","q":"Why does the largest known volcano in the solar system sit on Mars, not Earth?"},{"id":"moonbow","t":"earth","q":"Why can moonlight make a rainbow too, and why does it look almost white?"},{"id":"mountain-snow-aspect","t":"earth","q":"Why does snow on one side of a mountain last until summer while the other side is bare by spring?"},{"id":"mountains","t":"earth","q":"Why are there mountains?"},{"id":"mtn-above-treeline-life","t":"earth","q":"Why can moss and lichen survive on bare mountain rock where almost nothing else can grow?"},{"id":"mtn-air-colder-with-height","t":"earth","q":"Why is the top of a mountain so much colder when it's actually closer to the Sun?"},{"id":"mtn-alpine-plant-cushion","t":"earth","q":"Why do so many high mountain plants grow low, tight and round instead of tall like lowland plants?"},{"id":"mtn-altitude-sickness","t":"earth","q":"Why do climbers sometimes get headaches and feel sick just from climbing too high too fast?"},{"id":"mtn-andes-subduction","t":"earth","q":"Why does a long mountain range run down almost the whole edge of South America?"},{"id":"mtn-arete-horn","t":"earth","q":"Why do some mountain peaks end in a sharp point with knife-edge ridges instead of a rounded top?"},{"id":"mtn-boiling-point-lower","t":"earth","q":"Why does an egg take longer to boil on a high mountain even in bubbling water?"},{"id":"mtn-bottled-oxygen","t":"earth","q":"Why do most climbers carry bottled oxygen near the top of Everest?"},{"id":"mtn-chimborazo-bulge","t":"earth","q":"Why is a mountain shorter than Everest actually the closest point on Earth to outer space?"},{"id":"mtn-cirque-bowl","t":"earth","q":"Why do some mountain valleys begin as a giant armchair-shaped bowl instead of tapering to a point?"},{"id":"mtn-climb-high-sleep-low","t":"earth","q":"Why do mountain climbers deliberately climb up high in the day and then sleep lower down at night?"},{"id":"mtn-cloud-forest","t":"earth","q":"Why do some mountainsides stay draped in cloud almost every single day, growing a strange dripping forest?"},{"id":"mtn-death-zone","t":"earth","q":"Why is the air above 8,000 metres on a mountain nicknamed the death zone?"},{"id":"mtn-dome","t":"earth","q":"Why did some round, dome-shaped mountains form without any eruption at all?"},{"id":"mtn-echo-shout","t":"earth","q":"Why do mountains and valleys throw your shout back at you as an echo?"},{"id":"mtn-erosion-race","t":"earth","q":"Why do some mountains keep getting shorter even while the ground beneath them is still rising?"},{"id":"mtn-everest-remeasured","t":"earth","q":"Why did Everest's official height actually change in recent years?"},{"id":"mtn-everest-vs-maunakea","t":"earth","q":"Why isn't Mount Everest actually the biggest mountain on Earth?"},{"id":"mtn-exfoliation-domes","t":"earth","q":"Why do some mountains peel away in giant curved sheets of rock instead of crumbling into rubble?"},{"id":"mtn-fault-block","t":"earth","q":"Why do some mountains have one steep, cliff-like side and one gentle slope?"},{"id":"mtn-fold-layers","t":"earth","q":"Why do some mountain rock layers look bent and folded like a wrinkled rug?"},{"id":"mtn-freeze-thaw-crack","t":"earth","q":"Why can solid mountain rock crack apart just from water freezing inside it?"},{"id":"mtn-frostbite-cold","t":"earth","q":"Why do fingers and toes go numb and white before anywhere else on a freezing mountain?"},{"id":"mtn-granite-exposed-erosion","t":"earth","q":"Why do some mountains show off pale, speckled granite while others are made of rock full of ancient seashells?"},{"id":"mtn-high-altitude-people-adapt","t":"earth","q":"Why can some people who live permanently on high mountains breathe easily where visitors struggle?"},{"id":"mtn-highest-per-continent-argument","t":"earth","q":"Why is picking the 'highest mountain' on some continents actually an argument?"},{"id":"mtn-hoodoo-spires","t":"earth","q":"Why do some mountainsides erode into tall, thin rock towers instead of smooth slopes?"},{"id":"mtn-k2-harder","t":"earth","q":"Why do climbers consider K2 more dangerous than the taller Mount Everest?"},{"id":"mtn-kilimanjaro-shrinking-ice","t":"earth","q":"Why is Kilimanjaro's famous snowcap disappearing even though the mountain hasn't grown any shorter?"},{"id":"mtn-old-round-young-jagged","t":"earth","q":"Why do some mountains look smooth and rounded while others look sharp and jagged?"},{"id":"mtn-plateau-uplift","t":"earth","q":"Why is there a huge flat highland sitting behind the Himalayas instead of more jagged peaks?"},{"id":"mtn-prominence-vs-elevation","t":"earth","q":"Why do mountain lists sometimes skip a very tall peak right next to an even taller one?"},{"id":"mtn-red-blood-cells-acclimatize","t":"earth","q":"Why does spending a few weeks at altitude actually change what's in a climber's blood?"},{"id":"mtn-rockfall-weathering","t":"earth","q":"Why do rocks sometimes suddenly tumble off a mountain cliff with no earthquake or storm to blame?"},{"id":"mtn-scree-no-plants","t":"earth","q":"Why do scree slopes on mountains often stay almost completely bare of plants?"},{"id":"mtn-scree-slope-form","t":"earth","q":"Why do mountainsides sometimes have huge slopes of loose broken rock instead of solid cliff?"},{"id":"mtn-sky-island-species","t":"earth","q":"Why do isolated mountaintops sometimes have plants and animals found nowhere else on Earth?"},{"id":"mtn-snow-vs-glacier","t":"earth","q":"Why isn't every mountain with year-round snow on top actually home to a glacier?"},{"id":"mtn-snowline-latitude","t":"earth","q":"Why is the snowline much higher up a mountain near the equator than near the poles?"},{"id":"mtn-still-growing-gps","t":"earth","q":"Why can scientists say a mountain is still growing when nobody has ever felt it move?"},{"id":"mtn-sunburn-altitude","t":"earth","q":"Why do people burn faster in the sun on a mountain than at the beach on an equally sunny day?"},{"id":"mtn-table-flat-top","t":"earth","q":"Why does one famous mountain in South Africa have a perfectly flat top instead of a peak?"},{"id":"mtn-thin-air-not-less-oxygen","t":"earth","q":"Why do people get out of breath on a high mountain if the air is still 21 percent oxygen?"},{"id":"mtn-thin-soil-high-up","t":"earth","q":"Why is the soil on a high mountain slope usually so thin and stony compared to a valley floor?"},{"id":"mtn-treeline","t":"earth","q":"Why do trees suddenly stop growing partway up a mountain instead of thinning out gradually?"},{"id":"noctilucent-clouds","t":"earth","q":"Why do some clouds glow after the sky outside has gone dark?"},{"id":"noon-shifts-within-zone","t":"earth","q":"Why is true noon not the same clock time at both ends of one time zone?"},{"id":"obsidian-volcanic-glass","t":"earth","q":"Why can lava cool into something that looks and cuts like black glass?"},{"id":"oil-puddle-rainbow","t":"earth","q":"Why does a thin puddle of oil on a wet road show rainbow colours?"},{"id":"orographic-clouds","t":"earth","q":"Why does a cloud always seem to sit on top of the same mountain?"},{"id":"ozone","t":"earth","q":"Why do we need the ozone layer?"},{"id":"pahoehoe-aa-lava-types","t":"earth","q":"Why does the same lava sometimes harden smooth and ropy, and other times jagged and broken?"},{"id":"pendulum-clock-length","t":"earth","q":"Why does a grandfather clock's pendulum have to be exactly the right length to keep true time?"},{"id":"penitentes-andes","t":"earth","q":"Why does snow high in the Andes grow into a forest of tall icy spikes taller than a person?"},{"id":"permafrost-frozen","t":"earth","q":"Why does permafrost stay frozen all year, even in summer?"},{"id":"permafrost-thaw","t":"earth","q":"Why does thawing permafrost make the ground sink and buildings crack?"},{"id":"petrichor-smell","t":"earth","q":"Why does the ground smell so good after rain?"},{"id":"phreatic-eruption-steam-only","t":"earth","q":"Why can a volcano suddenly blast rock and steam into the air with no fresh magma involved at all?"},{"id":"pileus-cloud","t":"earth","q":"Why does a storm cloud sometimes wear a little cap on top?"},{"id":"polar-whiteout","t":"earth","q":"Why can you lose all sense of up and down on a snowfield with no snow falling at all?"},{"id":"polarised-sunglasses","t":"earth","q":"Why do polarised sunglasses cut glare off water when ordinary ones can't?"},{"id":"pompeii-vesuvius-facts","t":"earth","q":"Why did the people of Pompeii not simply flee when Vesuvius began erupting?"},{"id":"pool-shallow-illusion","t":"earth","q":"Why does a swimming pool always look shallower than it really is?"},{"id":"powder-snow","t":"earth","q":"Why is freshly fallen powder snow so light and fluffy?"},{"id":"prime-meridian-greenwich","t":"earth","q":"Why does the world measure time from a line through Greenwich?"},{"id":"prism-splits-light","t":"earth","q":"Why does a glass prism split white sunlight into a rainbow?"},{"id":"puddle-evaporate-no-boil","t":"earth","q":"Why does water disappear from a puddle without boiling?"},{"id":"puddle-freeze-edge-first","t":"earth","q":"Why does a puddle usually start freezing at its edges first, not in the middle?"},{"id":"puddle-soak-vs-evaporate","t":"earth","q":"Why can a puddle vanish on concrete but soak away on a garden bed?"},{"id":"pumice-floats","t":"earth","q":"Why can a chunk of volcanic rock float on water?"},{"id":"pyroclastic-flow-speed","t":"earth","q":"Why is a pyroclastic flow considered the deadliest thing a volcano can produce?"},{"id":"railway-time-standard","t":"earth","q":"Why did every town once keep its own separate time?"},{"id":"rain","t":"earth","q":"Why does it rain?"},{"id":"rain-chance-70","t":"earth","q":"Why doesn't \"70% chance of rain\" mean 70% of the sky gets wet?"},{"id":"rain-cloud-fall","t":"earth","q":"Why don't clouds just fall out of the sky as rain all the time?"},{"id":"rain-coming-smell","t":"earth","q":"Why can you smell rain coming before a drop falls?"},{"id":"rain-fresh-sea-salty","t":"earth","q":"Why does rain taste fresh when it comes from the salty sea?"},{"id":"rain-gauge-funnel","t":"earth","q":"Why do rain gauges use a funnel instead of a flat dish?"},{"id":"rain-miss-next-suburb","t":"earth","q":"Why can a storm flood one suburb and completely miss the next?"},{"id":"rain-mm-not-litres","t":"earth","q":"Why is rainfall measured in millimetres instead of litres?"},{"id":"rain-naturally-acidic","t":"earth","q":"Why is ordinary rain already a little bit acidic?"},{"id":"rain-smell-place","t":"earth","q":"Why does the smell of rain differ from place to place?"},{"id":"rain-soak-runoff","t":"earth","q":"Why doesn't all the rain in a storm soak straight into the ground?"},{"id":"rainbow","t":"earth","q":"Why do rainbows happen?"},{"id":"rainbow-after-rain-timing","t":"earth","q":"Why do rainbows appear right as a storm clears, not during the heaviest rain?"},{"id":"rainbow-angle-fixed","t":"earth","q":"Why is every rainbow the same size, whether it looks huge or small?"},{"id":"rainbow-colour-order","t":"earth","q":"Why is the order of colours in a rainbow always the same?"},{"id":"rainbow-dark-band","t":"earth","q":"Why does the strip of sky between a double rainbow's arcs look darker?"},{"id":"rainbow-double","t":"earth","q":"Why does a second, fainter rainbow sometimes appear above the first?"},{"id":"rainbow-full-circle-plane","t":"earth","q":"Why is a rainbow secretly a full circle, even though you only ever see an arc?"},{"id":"rainbow-needs-ingredients","t":"earth","q":"Why can't a planet like Mars ever get a rainbow the way Earth does?"},{"id":"rainbow-pot-of-gold-myth","t":"earth","q":"Why can you never actually walk to the end of a rainbow?"},{"id":"rainbow-seven-colours-myth","t":"earth","q":"Why do we always say a rainbow has seven colours?"},{"id":"rainbow-sun-altitude","t":"earth","q":"Why do you never see a rainbow around the middle of the day in summer?"},{"id":"rainbow-supernumerary","t":"earth","q":"Why do faint extra stripes sometimes show inside a rainbow's edge?"},{"id":"rainbow-waterfall","t":"earth","q":"Why do rainbows so often appear at the bottom of a waterfall?"},{"id":"raindrop-max-size","t":"earth","q":"Why can't a raindrop grow bigger than a housefly?"},{"id":"raindrop-shape","t":"earth","q":"Why aren't raindrops shaped like teardrops?"},{"id":"raindrop-speed","t":"earth","q":"Why do raindrops fall gently even from kilometres up?"},{"id":"raindrop-splash-rings","t":"earth","q":"Why do raindrops make rings spread across a puddle?"},{"id":"retroreflector","t":"earth","q":"Why do bike reflectors blaze brightly in headlights but look dull otherwise?"},{"id":"richter-scale-obsolete","t":"earth","q":"Why don't scientists actually use the Richter scale any more?"},{"id":"rime-ice","t":"earth","q":"Why does rime ice grow feathery spikes pointing into the wind?"},{"id":"ring-of-fire","t":"earth","q":"Why do most of the world's volcanoes and big earthquakes cluster around the same horseshoe-shaped ring?"},{"id":"river-ice-danger","t":"earth","q":"Why is ice on a flowing river more dangerous than ice on a still lake?"},{"id":"rivers-bend","t":"earth","q":"Why aren't rivers straight?"},{"id":"road-grit-salt-limit","t":"earth","q":"Why do snowploughs sometimes spread sand instead of salt on icy roads?"},{"id":"salt-melts-ice","t":"earth","q":"Why does throwing salt on an icy footpath melt the ice?"},{"id":"same-rain-different-chaos","t":"earth","q":"Why can the same amount of rain be nothing in one place and chaos in another?"},{"id":"sand","t":"earth","q":"Why is there sand?"},{"id":"sastrugi-wind-ridges","t":"earth","q":"Why does polar snow get carved into hard, wavy ridges instead of lying flat?"},{"id":"sea-breeze","t":"earth","q":"Why is it always windy at the beach?"},{"id":"sea-ice-brine","t":"earth","q":"Why does old sea ice taste less salty than new sea ice?"},{"id":"sea-ice-vs-iceberg","t":"earth","q":"Why are icebergs and sea ice actually two different things?"},{"id":"sea-salty","t":"earth","q":"Why is the sea salty?"},{"id":"seasons","t":"earth","q":"Why do we have seasons?"},{"id":"seasons-aboriginal-six-seasons","t":"earth","q":"Why do some Aboriginal calendars describe six seasons instead of four?"},{"id":"seasons-arctic-circle-line","t":"earth","q":"Why is there an invisible line on the map called the Arctic Circle?"},{"id":"seasons-axis-fixed-direction","t":"earth","q":"Why does Earth's tilted axis keep pointing at the same spot in the sky all year?"},{"id":"seasons-continental-swing","t":"earth","q":"Why do places deep inside a continent swing between scorching summers and freezing winters?"},{"id":"seasons-date-shifts-yearly","t":"earth","q":"Why does the first day of a season fall on a slightly different date almost every year?"},{"id":"seasons-day-length-change","t":"earth","q":"Why do the days get longer and shorter through the year?"},{"id":"seasons-daylength-change-rate","t":"earth","q":"Why do the days lengthen fastest around the equinoxes rather than the solstices?"},{"id":"seasons-dry-wet-naming","t":"earth","q":"Why is the same time of year called \"winter\" in one country and the \"dry season\" in another?"},{"id":"seasons-egg-balance-myth","t":"earth","q":"Why can you actually balance an egg on its end on any day of the year, not just the equinox?"},{"id":"seasons-equator-mild","t":"earth","q":"Why does the equator barely have seasons at all?"},{"id":"seasons-equinox-not-equal","t":"earth","q":"Why isn't day exactly the same length as night on the equinox?"},{"id":"seasons-frost-date","t":"earth","q":"Why do gardeners keep track of the \"last frost date\" every year?"},{"id":"seasons-groundhog-myth","t":"earth","q":"Why can't a groundhog's shadow actually predict when spring will arrive?"},{"id":"seasons-growing-season-latitude","t":"earth","q":"Why does the farming season get shorter the further you travel from the equator?"},{"id":"seasons-heatwave-vs-summer","t":"earth","q":"Why can a heatwave strike in spring, weeks before summer officially starts?"},{"id":"seasons-hemisphere-opposite","t":"earth","q":"Why does the Southern Hemisphere have summer at Christmas while the north shivers through winter?"},{"id":"seasons-hemisphere-symmetry-not-exact","t":"earth","q":"Why isn't a Sydney summer a perfect mirror of a London winter, even though they're opposite seasons at once?"},{"id":"seasons-mars-seasons","t":"earth","q":"Why does Mars have seasons, just like Earth does?"},{"id":"seasons-mercury-no-seasons","t":"earth","q":"Why does Mercury have almost no seasons at all?"},{"id":"seasons-meteorological-vs-astronomical","t":"earth","q":"Why do weather forecasters start summer on the first of the month instead of waiting for the solstice?"},{"id":"seasons-north-pole-sun","t":"earth","q":"Why does the Sun never set at the North Pole for months at a time?"},{"id":"seasons-ocean-lag","t":"earth","q":"Why do seaside towns feel like summer or winter later than towns further inland?"},{"id":"seasons-perihelion-january","t":"earth","q":"Why is Earth actually closest to the Sun in January, right when the north is freezing?"},{"id":"seasons-polar-ice-cold-feedback","t":"earth","q":"Why does ice on the ground near the poles make winter there colder still?"},{"id":"seasons-precession-wobble","t":"earth","q":"Why does the direction Earth's axis points slowly change over thousands of years?"},{"id":"seasons-same-latitude-different-climate","t":"earth","q":"Why can two cities on the same latitude line have very different seasons?"},{"id":"seasons-shadow-length","t":"earth","q":"Why is your shadow at lunchtime shorter in summer than in winter?"},{"id":"seasons-shortest-day-june","t":"earth","q":"Why is the shortest day of the year in June for half the planet and December for the other half?"},{"id":"seasons-snow-albedo-cold","t":"earth","q":"Why can a blanket of snow on the ground make a cold snap last even longer?"},{"id":"seasons-solstice-name","t":"earth","q":"Why is \"solstice\" named after the Sun standing still?"},{"id":"seasons-solstice-not-hottest","t":"earth","q":"Why isn't the longest day of the year also the hottest?"},{"id":"seasons-south-pole-dark","t":"earth","q":"Why does the South Pole sit in total darkness for half the year?"},{"id":"seasons-southern-summer-shorter","t":"earth","q":"Why is summer a few days shorter in the Southern Hemisphere than in the Northern Hemisphere?"},{"id":"seasons-spring-cooler-than-autumn","t":"earth","q":"Why is spring usually cooler than autumn, even on days with exactly the same amount of daylight?"},{"id":"seasons-spring-not-steady-climb","t":"earth","q":"Why does spring arrive in fits and starts instead of a steady climb in temperature?"},{"id":"seasons-stonehenge","t":"earth","q":"Why did ancient people build huge stone monuments to track the solstices?"},{"id":"seasons-sun-path-height","t":"earth","q":"Why does the Sun climb higher in the sky in summer than in winter?"},{"id":"seasons-sunrise-position-shift","t":"earth","q":"Why does the Sun rise from a different spot on the horizon depending on the season?"},{"id":"seasons-thermal-lag-coldest","t":"earth","q":"Why is the coldest day of winter not the shortest day?"},{"id":"seasons-tilt-angle-235","t":"earth","q":"Why is Earth tilted by 23.5 degrees instead of standing up straight?"},{"id":"seasons-tropic-lines","t":"earth","q":"Why do the Tropic of Cancer and Tropic of Capricorn sit exactly where they do on a map?"},{"id":"seasons-unequal-lengths","t":"earth","q":"Why don't the four seasons all last the same number of days?"},{"id":"seasons-uranus-21-years","t":"earth","q":"Why does each season on Uranus last about twenty-one years?"},{"id":"seasons-wind-shift","t":"earth","q":"Why does a change of season sometimes announce itself with a change in the wind rather than the temperature?"},{"id":"seasons-winter-sun-weaker","t":"earth","q":"Why does winter sunlight feel weaker even though it's the same Sun?"},{"id":"seiche-lake-wave","t":"earth","q":"Why can a lake slosh back and forth for hours after an earthquake, far from any ocean?"},{"id":"seismic-p-and-s-waves","t":"earth","q":"Why do earthquakes send out two completely different kinds of shockwaves?"},{"id":"seismic-wave-speed-locate-epicentre","t":"earth","q":"Why can scientists pinpoint an earthquake's location just from when its shockwaves arrive?"},{"id":"seismograph-bedrock-anchor","t":"earth","q":"Why do the best earthquake sensors need to be bolted right down into solid bedrock?"},{"id":"sheet-lightning","t":"earth","q":"Why does sheet lightning light up a whole cloud with no clear bolt?"},{"id":"shield-volcano-shape","t":"earth","q":"Why do some volcanoes look like a wide, gently sloping shield instead of a tall pointy cone?"},{"id":"sidereal-solar-day","t":"earth","q":"Why is a day measured by the stars four minutes shorter than a day measured by the Sun?"},{"id":"ski-wax-snow-temp","t":"earth","q":"Why do skiers rub different coloured wax onto their skis depending on the day's temperature?"},{"id":"sky-blue","t":"earth","q":"Why is the sky blue?"},{"id":"sleet-forms","t":"earth","q":"Why does sleet fall as icy pellets instead of snow or rain?"},{"id":"snow","t":"earth","q":"Why does it snow in some places and not others?"},{"id":"snow-blindness-eyes","t":"earth","q":"Why can staring at snow on a sunny day damage your eyes?"},{"id":"snow-crust","t":"earth","q":"Why does old snow turn hard and crunchy instead of staying soft?"},{"id":"snow-dirty-melt-fast","t":"earth","q":"Why does snow beside a road turn dark and disappear long before clean snow on a lawn?"},{"id":"snow-eating-dehydrate","t":"earth","q":"Why can eating snow to quench your thirst actually leave you more dehydrated?"},{"id":"snow-in-australia","t":"earth","q":"Why does it ever snow in Australia?"},{"id":"snow-inuit-words","t":"earth","q":"Why do people say Arctic languages have dozens of words for snow?"},{"id":"snow-making-machine","t":"earth","q":"Why can snow machines make snow even when it's barely below freezing?"},{"id":"snow-muffles-sound","t":"earth","q":"Why does fresh snow make everything sound so quiet?"},{"id":"snow-pit-test","t":"earth","q":"Why do backcountry skiers dig a pit in the snow before setting off?"},{"id":"snow-roof-collapse","t":"earth","q":"Why can a metre of snow on a roof be far more dangerous than it looks?"},{"id":"snow-squall-sudden","t":"earth","q":"Why can winter driving conditions turn deadly within minutes on a day that started clear?"},{"id":"snow-squeak","t":"earth","q":"Why does snow squeak under your boots on a really cold day?"},{"id":"snow-to-glacier","t":"earth","q":"Why does snow need years to turn into solid glacier ice?"},{"id":"snow-water-equivalent","t":"earth","q":"Why do forecasters measure a snowpack in millimetres of water instead of centimetres of snow?"},{"id":"snow-white","t":"earth","q":"Why does snow look white when the ice inside it is clear?"},{"id":"snowball-pack-temp","t":"earth","q":"Why won't snow pack into a snowball on the coldest days?"},{"id":"snowflake-clump-mild","t":"earth","q":"Why do the biggest, fluffiest snowflakes fall only on the mildest snowy days?"},{"id":"snowflake-shapes-temperature","t":"earth","q":"Why do snowflakes come out as flat plates in one storm and feathery stars in another?"},{"id":"snowflake-six-sides","t":"earth","q":"Why do snowflakes always have six sides?"},{"id":"snowflake-unique","t":"earth","q":"Why is it said that no two snowflakes are ever alike?"},{"id":"snowpack-depth-hoar","t":"earth","q":"Why can snow that looks solid on top hide a crumbly, sugary layer underneath?"},{"id":"snowshoes-spread-weight","t":"earth","q":"Why do snowshoes stop you from sinking into deep snow that would swallow an ordinary boot?"},{"id":"soap-bubble-colours","t":"earth","q":"Why do soap bubbles swirl with rainbow colours when soap itself isn't coloured?"},{"id":"soil-brown","t":"earth","q":"Why is soil brown?"},{"id":"solar-day-length-varies","t":"earth","q":"Why isn't every single day exactly 24 hours long?"},{"id":"spin-speed-unfelt","t":"earth","q":"Why can't you feel the Earth spinning, even though it's moving faster than a jet?"},{"id":"spit-dry-cold","t":"earth","q":"Why does your skin feel cold when spit or sweat dries on it?"},{"id":"spoon-reflection-flip","t":"earth","q":"Why does your reflection flip upside down on one side of a shiny spoon?"},{"id":"stalactites","t":"earth","q":"Why do caves have stone icicles?"},{"id":"star-twinkle","t":"earth","q":"Why do stars twinkle more near the horizon than overhead?"},{"id":"storm-30-second-rule","t":"earth","q":"Why should thunder within 30 seconds of a flash send you straight indoors?"},{"id":"storm-car-safety","t":"earth","q":"Why is a car safe in a lightning storm — and why isn't it the tyres?"},{"id":"storm-count-gap","t":"earth","q":"Why can counting seconds after a flash tell you how far away a storm is?"},{"id":"storm-crouch-position","t":"earth","q":"Why should you crouch low instead of lying flat if caught outside in a storm?"},{"id":"storm-eye-calm","t":"earth","q":"Why is the eye of a cyclone eerily calm while the storm rages around it?"},{"id":"storm-eye-danger","t":"earth","q":"Why does the calm in a storm's eye trick people into danger?"},{"id":"storm-eye-sunshine","t":"earth","q":"Why can the sun come out in the middle of a hurricane?"},{"id":"storm-lightning-after-rain","t":"earth","q":"Why can lightning still strike after the rain has already stopped?"},{"id":"storm-pool-danger","t":"earth","q":"Why is a swimming pool a dangerous place to be in a thunderstorm?"},{"id":"storm-spin-hemisphere","t":"earth","q":"Why do storms spin opposite ways north and south of the equator?"},{"id":"storm-surge-deadly","t":"earth","q":"Why is a cyclone's storm surge often more deadly than its wind?"},{"id":"storm-surge-lopsided","t":"earth","q":"Why is a storm surge much worse on one side of a cyclone than the other?"},{"id":"storm-surge-pileup","t":"earth","q":"Why does a storm push a wall of seawater onto the coast?"},{"id":"storm-tent-shelter","t":"earth","q":"Why doesn't a tent protect you from lightning the way a car does?"},{"id":"storm-tree-danger","t":"earth","q":"Why is it never safe to shelter under a tree in a storm?"},{"id":"stratovolcano-cone-shape","t":"earth","q":"Why do the classic pointy, snow-capped volcanoes form such steep cones?"},{"id":"straw-bent-water","t":"earth","q":"Why does a straw look bent right where it enters a glass of water?"},{"id":"submarine-volcano-most-common","t":"earth","q":"Why does most of Earth's volcanic activity happen where almost nobody ever sees it?"},{"id":"sun-astronaut-radiation","t":"earth","q":"Why do astronauts need special shielding once they travel beyond Earth's protective bubble?"},{"id":"sun-aurora-cause","t":"earth","q":"Why do glowing lights sometimes ripple across the sky near the North and South Poles?"},{"id":"sun-aurora-colours","t":"earth","q":"Why do auroras glow in different colours like green, red and pink?"},{"id":"sun-aurora-poles","t":"earth","q":"Why do auroras usually only appear near the North and South Poles?"},{"id":"sun-aurora-sound","t":"earth","q":"Why do some people say they can hear the aurora crackling?"},{"id":"sun-carrington-event","t":"earth","q":"Why did a solar storm in 1859 set telegraph offices on fire?"},{"id":"sun-chlorophyll-green","t":"earth","q":"Why do plants look green instead of soaking up every colour of sunlight?"},{"id":"sun-dark-surface-hot","t":"earth","q":"Why does a dark car seat get much hotter in the sun than a pale one?"},{"id":"sun-desert-temperature-swing","t":"earth","q":"Why can a desert be scorching by day and freezing by night?"},{"id":"sun-dog","t":"earth","q":"Why do two bright spots sometimes appear on either side of the Sun?"},{"id":"sun-eclipse-cooling","t":"earth","q":"Why does the temperature actually drop during a total solar eclipse?"},{"id":"sun-eclipse-glasses","t":"earth","q":"Why won't ordinary sunglasses protect your eyes during a solar eclipse?"},{"id":"sun-ionosphere-radio","t":"earth","q":"Why do some radio stations carry much further at night than during the day?"},{"id":"sun-look-directly-danger","t":"earth","q":"Why is it dangerous to look straight at the Sun, even for a moment?"},{"id":"sun-magnifying-glass-fire","t":"earth","q":"Why can a magnifying glass focused on the Sun scorch a leaf even though sunlight alone barely warms it?"},{"id":"sun-moon-temperature-swing","t":"earth","q":"Why does the Moon swing between scorching and freezing while Earth stays far more comfortable?"},{"id":"sun-ocean-currents-heat","t":"earth","q":"Why does the Sun's heat help drive huge ocean currents like the Gulf Stream?"},{"id":"sun-photosynthesis-efficiency","t":"earth","q":"Why do plants only manage to capture about 1% of the sunlight that lands on them?"},{"id":"sun-photosynthesis-need","t":"earth","q":"Why can't a plant grow properly without sunlight?"},{"id":"sun-photosynthesis-oxygen","t":"earth","q":"Why does sunlight hitting a leaf eventually end up as the oxygen you breathe?"},{"id":"sun-plant-lean-window","t":"earth","q":"Why do houseplants lean and grow towards a window?"},{"id":"sun-shower","t":"earth","q":"Why can it rain while the Sun is still shining?"},{"id":"sun-solar-panel-electricity","t":"earth","q":"Why can a flat panel turn sunlight directly into electricity with no moving parts?"},{"id":"sun-solar-wind","t":"earth","q":"Why is there a constant \"wind\" blowing from the Sun that isn't made of air?"},{"id":"sun-spring-neap-tide","t":"earth","q":"Why are some high tides much higher than others across a single month?"},{"id":"sun-squashed","t":"earth","q":"Why does the setting Sun often look squashed into an oval?"},{"id":"sun-sunscreen-works","t":"earth","q":"Why does rubbing on sunscreen stop you from burning?"},{"id":"sun-sunspots","t":"earth","q":"Why does the Sun have dark spots on it?"},{"id":"sun-tan-skin","t":"earth","q":"Why does skin go darker after time in the sun?"},{"id":"sun-tide-pull","t":"earth","q":"Why does the Sun also pull on Earth's oceans, even though the Moon causes most of the tide?"},{"id":"sun-train-track-gaps","t":"earth","q":"Why do railway tracks and bridges need small gaps to cope with the Sun's heat?"},{"id":"sun-travel-time-8min","t":"earth","q":"Why does it take a beam of sunlight about eight minutes to reach you?"},{"id":"sun-uv-index","t":"earth","q":"Why do weather forecasts give a UV number instead of just a temperature?"},{"id":"sun-uv-midday-strongest","t":"earth","q":"Why is the Sun's ultraviolet light strongest around midday rather than at sunrise or sunset?"},{"id":"sun-vitamin-d","t":"earth","q":"Why does your skin make vitamin D when sunlight touches it?"},{"id":"sunburn-cloudy-day-2","t":"earth","q":"Why can you get sunburnt on a cool, cloudy day?"},{"id":"sunburn-peel-2","t":"earth","q":"Why does sunburnt skin peel off a few days later?"},{"id":"sunburn-snow-glare","t":"earth","q":"Why do skiers get sunburnt under their chin and inside their nostrils?"},{"id":"sunburn-underwater","t":"earth","q":"Why can you still get sunburnt while swimming underwater?"},{"id":"sunburn-window-glass","t":"earth","q":"Why can't you usually get sunburnt sitting behind a closed car window?"},{"id":"sundial-shadow-time","t":"earth","q":"Why can a stick's shadow on the ground tell you roughly what time it is?"},{"id":"sundogs","t":"earth","q":"Why are there sometimes two bright spots of light beside the Sun?"},{"id":"sunrise-east","t":"earth","q":"Why does the Sun always rise in the east?"},{"id":"sunset-delay-refraction","t":"earth","q":"Why can you still see the Sun minutes after it has technically set?"},{"id":"sunset-red","t":"earth","q":"Why are sunsets red?"},{"id":"supervolcano-definition","t":"earth","q":"Why does calling something a \"supervolcano\" mean more than just a big eruption?"},{"id":"supervolcano-not-overdue","t":"earth","q":"Why don't scientists say Yellowstone is \"overdue\" for a supereruption?"},{"id":"thunder-charge-buildup","t":"earth","q":"Why does a storm cloud build up a huge electric charge?"},{"id":"thunder-ground-charge","t":"earth","q":"Why does the ground under a storm cloud gather its own electric charge?"},{"id":"thunder-hair-stand","t":"earth","q":"Why can your hair stand on end just before lightning strikes nearby?"},{"id":"thunder-lightning","t":"earth","q":"Why does thunder come after lightning?"},{"id":"thunder-rumble","t":"earth","q":"Why does thunder rumble on and on instead of one sharp bang?"},{"id":"thunder-why-sound","t":"earth","q":"Why does lightning make any sound at all?"},{"id":"thundersnow-storm","t":"earth","q":"Why can lightning flash and thunder rumble during a snowstorm?"},{"id":"timezone-invention","t":"earth","q":"Why do we have time zones at all?"},{"id":"timezone-not-straight-lines","t":"earth","q":"Why do time zone maps zigzag instead of following straight lines of longitude?"},{"id":"titan-clouds","t":"earth","q":"Why does it rain liquid gas on Saturn's moon Titan?"},{"id":"too-cold-to-snow","t":"earth","q":"Why can it be too cold for snow to fall?"},{"id":"tornado-form","t":"earth","q":"Why do some thunderstorms spin off a tornado while most never do?"},{"id":"tornado-funnel-shape","t":"earth","q":"Why does a tornado look like a spinning funnel?"},{"id":"tornado-invisible","t":"earth","q":"Why can a tornado be tearing along before you can even see it?"},{"id":"tornado-roar","t":"earth","q":"Why do tornadoes roar like a freight train?"},{"id":"transform-fault-san-andreas","t":"earth","q":"Why does the San Andreas Fault cause earthquakes without building any mountains or ocean trenches?"},{"id":"tsunami-2004-calm-before","t":"earth","q":"Why did people on the beach in 2004 see nothing wrong just minutes before a deadly tsunami arrived?"},{"id":"tsunami-bay-harbour-danger","t":"earth","q":"Why are narrow bays and harbours often hit harder by a tsunami than open, straight coastlines?"},{"id":"tsunami-multiple-hours","t":"earth","q":"Why do tsunami warnings often stay in effect for many hours after the very first wave arrives?"},{"id":"tsunami-only-vertical-motion-earthquakes","t":"earth","q":"Why do some undersea earthquakes cause a tsunami while others of a similar size don't?"},{"id":"tsunami-open-ocean-tiny","t":"earth","q":"Why is a tsunami barely noticeable to ships out in the middle of the ocean?"},{"id":"tsunami-sea-recedes-first","t":"earth","q":"Why does the sea sometimes pull back dramatically from a beach just before a tsunami hits?"},{"id":"tsunami-series-not-one-wave","t":"earth","q":"Why is a tsunami never just one giant wave?"},{"id":"tsunami-shallow-water-grows","t":"earth","q":"Why does a tsunami suddenly grow from a gentle swell into a towering wave near the coast?"},{"id":"tsunami-speed-jet-plane","t":"earth","q":"Why can a tsunami cross an entire ocean in less than a day?"},{"id":"tsunami-up-river","t":"earth","q":"Why can a tsunami travel far up a river, flooding towns nowhere near the open coast?"},{"id":"tsunami-warning-buoy-deep-sea","t":"earth","q":"Why do tsunami warning buoys sit anchored to the deep ocean floor instead of floating freely?"},{"id":"tsunami-wavelength-huge","t":"earth","q":"Why is a tsunami's wavelength so much longer than an ordinary wind-driven wave?"},{"id":"twilight-lag","t":"earth","q":"Why doesn't the sky go dark the instant the Sun disappears?"},{"id":"twilight-polar-summer","t":"earth","q":"Why can the sky in Norway or Alaska stay bright all night in summer?"},{"id":"twilight-three-stages","t":"earth","q":"Why do astronomers split evening twilight into three separate stages?"},{"id":"two-mirrors-infinity","t":"earth","q":"Why do two facing mirrors create an endless tunnel of reflections?"},{"id":"underwater-landslide-tsunami","t":"earth","q":"Why can a tsunami happen even without any earthquake at all?"},{"id":"utc-world-clock","t":"earth","q":"Why do pilots and scientists use one single UTC clock instead of local time?"},{"id":"venus-backward-spin","t":"earth","q":"Why does the Sun rise in the west if you're standing on Venus?"},{"id":"venus-clouds","t":"earth","q":"Why are Venus's clouds made of acid instead of water?"},{"id":"venus-day-longer-year","t":"earth","q":"Why is a single day on Venus longer than its whole year?"},{"id":"vertical-evacuation-tower","t":"earth","q":"Why do some coastal towns build tall towers just for people to run up during a tsunami?"},{"id":"virga-rain","t":"earth","q":"Why does rain sometimes evaporate before it reaches the ground?"},{"id":"volcanic-ash-not-soft","t":"earth","q":"Why is volcanic ash dangerous even though it looks and falls a bit like soft grey snow?"},{"id":"volcanic-bombs","t":"earth","q":"Why does chunks of lava thrown from a volcano sometimes land already twisted into odd, aerodynamic shapes?"},{"id":"volcanic-crystal-growth-time","t":"earth","q":"Why can some volcanic rocks contain crystals large enough to see, while most of the same rock is too fine-grained to make out at all?"},{"id":"volcanic-gas-danger","t":"earth","q":"Why can a volcano be deadly without erupting any lava or ash at all?"},{"id":"volcanic-island-formation","t":"earth","q":"Why do some islands rise straight up out of the open ocean with no continent nearby?"},{"id":"volcanic-tsunami","t":"earth","q":"Why can a volcano erupting near the coast set off a tsunami?"},{"id":"volcanic-winter-climate","t":"earth","q":"Why can a single huge volcanic eruption cool the entire planet for a year or more afterward?"},{"id":"volcano","t":"earth","q":"Why do volcanoes erupt?"},{"id":"volcano-crater-lake-colour","t":"earth","q":"Why can a volcano's crater lake turn a startling turquoise, or even blood red?"},{"id":"volcano-different-planets-moons","t":"earth","q":"Why does one of Jupiter's moons have more active volcanoes erupting right now than Earth does?"},{"id":"volcano-eruption-columns-height","t":"earth","q":"Why can a volcanic ash cloud rise higher into the sky than any passenger plane ever flies?"},{"id":"volcano-fertile-soil","t":"earth","q":"Why do farmers keep living on the slopes of dangerous volcanoes instead of moving away for good?"},{"id":"volcano-lightning","t":"earth","q":"Why can lightning flash inside a volcano's ash cloud with no storm anywhere nearby?"},{"id":"volcano-name-origin","t":"earth","q":"Why is the word \"volcano\" borrowed from the name of an ancient god?"},{"id":"volcano-not-core","t":"earth","q":"Why isn't lava actually melted rock from the Earth's core?"},{"id":"volcano-not-plate-boundary","t":"earth","q":"Why does Hawaii have huge volcanoes when it sits in the middle of a tectonic plate, nowhere near an edge?"},{"id":"volcano-warning-signs","t":"earth","q":"Why can scientists often tell a volcano is about to erupt days before it actually happens?"},{"id":"washing-dry-wind","t":"earth","q":"Why does washing dry faster on a windy day than a still one?"},{"id":"water-cycle","t":"earth","q":"Why doesn't the Earth run out of water?"},{"id":"water-nine-days","t":"earth","q":"Why might today's raindrop have last fallen as rain only nine days ago?"},{"id":"water-older-than-earth","t":"earth","q":"Why could the water in your glass be older than the Earth itself?"},{"id":"watermelon-snow-algae","t":"earth","q":"Why can snow high on a mountain turn pink, like a giant watermelon slushy?"},{"id":"wettest-hills-india","t":"earth","q":"Why is a small patch of Indian hills among the wettest places on Earth?"},{"id":"why-clouds-not-vapour","t":"earth","q":"Why aren't clouds just water vapour, if that's what makes them?"},{"id":"why-not-every-mountain-volcano","t":"earth","q":"Why isn't every tall, pointed mountain actually a volcano, even though many look alike from a distance?"},{"id":"why-not-predict-exact-eruption","t":"earth","q":"Why can't scientists say exactly which day a volcano will erupt, even with all their instruments?"},{"id":"wind","t":"earth","q":"Why does the wind blow?"},{"id":"wind-aeolian-sound","t":"earth","q":"Why does wind make wires and fences whistle and hum?"},{"id":"wind-afternoon-breeze","t":"earth","q":"Why does the wind almost always pick up in the afternoon and drop off after dark, even far from the coast?"},{"id":"wind-anabatic","t":"earth","q":"Why does wind sometimes blow uphill during the day?"},{"id":"wind-anemometer-cups","t":"earth","q":"Why do wind speed gauges use spinning cups instead of a spinning blade?"},{"id":"wind-antarctica-windiest","t":"earth","q":"Why is Antarctica the windiest continent on Earth?"},{"id":"wind-balloon-steering","t":"earth","q":"Why can't a hot air balloon be steered like a plane?"},{"id":"wind-beaufort-scale","t":"earth","q":"Why was wind speed once measured by watching a ship's sails, not an instrument?"},{"id":"wind-bird-soaring","t":"earth","q":"Why do soaring birds circle instead of flying straight?"},{"id":"wind-boundary-layer","t":"earth","q":"Why does wind feel stronger the higher up you go?"},{"id":"wind-chill-feel","t":"earth","q":"Why does a windy winter day feel colder than the thermometer says?"},{"id":"wind-chill-threshold","t":"earth","q":"Why do weather forecasts stop mentioning wind chill once the day warms up?"},{"id":"wind-chinook-snow-eater","t":"earth","q":"Why is the Chinook wind nicknamed the snow eater?"},{"id":"wind-city-gusts","t":"earth","q":"Why do city streets between tall buildings get sudden, fierce gusts?"},{"id":"wind-cycling-noise","t":"earth","q":"Why does wind roar in your ears when you ride a bike fast on a still day?"},{"id":"wind-doldrums","t":"earth","q":"Why did sailors dread a calm patch of ocean called the doldrums?"},{"id":"wind-dust-devil-vs-tornado","t":"earth","q":"Why is a dust devil not just a small tornado?"},{"id":"wind-fan-cooling","t":"earth","q":"Why does sitting in front of a fan cool you down when the air itself isn't cold?"},{"id":"wind-flag-flap","t":"earth","q":"Why does a flag flap and snap instead of streaming out smoothly in the wind?"},{"id":"wind-flight-times","t":"earth","q":"Why can a flight take an hour longer one way than it does coming back?"},{"id":"wind-foehn-warming","t":"earth","q":"Why can a wind blowing down a mountain make the temperature jump within minutes?"},{"id":"wind-gust-vs-sustained","t":"earth","q":"Why do weather reports give two different wind speeds for the same storm?"},{"id":"wind-harmattan","t":"earth","q":"Why does a dusty haze roll across West Africa every year?"},{"id":"wind-horse-latitudes","t":"earth","q":"Why is a windless band of ocean nicknamed the horse latitudes?"},{"id":"wind-isobar-map","t":"earth","q":"Why do weather maps with tightly packed lines mean a windy day is coming?"},{"id":"wind-jet-stream","t":"earth","q":"Why is there a river of wind blowing far above your head right now?"},{"id":"wind-jet-stream-shift","t":"earth","q":"Why does the jet stream wander instead of staying in one place?"},{"id":"wind-katabatic","t":"earth","q":"Why does cold air come pouring down a mountainside after dark?"},{"id":"wind-kite-lift","t":"earth","q":"Why does a kite need wind to fly at all?"},{"id":"wind-leaf-flip","t":"earth","q":"Why do some trees show their pale undersides just before a storm?"},{"id":"wind-mistral","t":"earth","q":"Why does the Mistral wind of southern France blow for days without easing?"},{"id":"wind-mountain-summit","t":"earth","q":"Why is a mountain summit almost always windier than the valley below?"},{"id":"wind-named-from","t":"earth","q":"Why does a north wind blow from the north instead of toward it?"},{"id":"wind-puddle-freeze","t":"earth","q":"Why does a puddle freeze faster on a windy night than a still one?"},{"id":"wind-sailing-against","t":"earth","q":"Why can a sailing boat travel against the wind?"},{"id":"wind-santa-ana","t":"earth","q":"Why do hot, dry winds make wildfires so much more dangerous in California?"},{"id":"wind-sirocco-dust","t":"earth","q":"Why can dust from the Sahara Desert turn rain red thousands of kilometres away in Europe?"},{"id":"wind-sock-airport","t":"earth","q":"Why does an airport windsock tell a pilot more than just wind direction?"},{"id":"wind-thermal-glider","t":"earth","q":"Why can a glider climb higher in the sky without any engine at all?"},{"id":"wind-trade-direction","t":"earth","q":"Why do trade winds blow at an angle instead of straight toward the equator?"},{"id":"wind-trade-etymology","t":"earth","q":"Why are steady ocean winds called trade winds?"},{"id":"wind-tree-creak","t":"earth","q":"Why do trees creak and groan in a strong wind?"},{"id":"wind-tree-lean","t":"earth","q":"Why do trees on a windy coast all lean the same way, permanently?"},{"id":"wind-turbine-speeds","t":"earth","q":"Why do wind turbines sit motionless on some breezy days but shut down on the stormiest ones?"},{"id":"wind-valley-channel","t":"earth","q":"Why does wind blow hard and steady through some mountain passes?"},{"id":"wind-willy-willy","t":"earth","q":"Why do small spinning whirls of dust appear on a hot, calm day?"},{"id":"year-not-whole-days","t":"earth","q":"Why doesn't a year divide evenly into a whole number of days?"},{"id":"abacus-beads","t":"people","q":"Why can sliding beads on an abacus add up numbers so fast?"},{"id":"abc-order","t":"people","q":"Why is the alphabet in that exact order and not some other order?"},{"id":"accent-critical-period","t":"people","q":"Why is it so hard to lose an accent once you're grown up?"},{"id":"accent-not-wrong","t":"people","q":"Why is there no such thing as speaking without any accent?"},{"id":"accent-own","t":"people","q":"Why can't you hear your own accent?"},{"id":"accent-regions","t":"people","q":"Why do neighbouring towns sometimes end up with different accents?"},{"id":"adopted-belong","t":"people","q":"Why do adopted kids belong just as much as kids born into a family?"},{"id":"advent-calendar-doors","t":"people","q":"Why do advent calendars have a door for each day?"},{"id":"age-limits-different","t":"people","q":"Why can you drive at 17 in some places, but not vote or drink until years later?"},{"id":"alaska-not-connected","t":"people","q":"Why is Alaska part of the United States even though Canada sits between it and the other states?"},{"id":"algorithm-name","t":"people","q":"Why does the word \"algorithm\" come from a mathematician who lived 1,200 years ago?"},{"id":"alphabet-size","t":"people","q":"Why do some alphabets have only 12 letters while others need 74?"},{"id":"ancient-greek-blue","t":"people","q":"Why did ancient Greek writers call the sea 'wine-dark' instead of blue?"},{"id":"animal-not-language","t":"people","q":"Why isn't a parrot saying 'hello' actually speaking English?"},{"id":"animal-sounds-differ","t":"people","q":"Why does a dog say 'woof' in English but 'wan wan' in Japanese?"},{"id":"antarctica-no-country","t":"people","q":"Why doesn't Antarctica belong to any country?"},{"id":"apostrophe-origin","t":"people","q":"Why does the same little mark show up in both \"don't\" and \"the dog's bone\"?"},{"id":"apportionment-population","t":"people","q":"Why does one region get more elected representatives than another, even in the same country?"},{"id":"arabic-numerals-india","t":"people","q":"Why are \"Arabic numerals\" actually invented in India, not Arabia?"},{"id":"art","t":"people","q":"Why do people make art?"},{"id":"attempted-crime-illegal","t":"people","q":"Why can someone still be charged with a crime even if they tried it and completely failed?"},{"id":"baby-babble","t":"people","q":"Why do babies babble 'ba-ba-ba' before they say real words?"},{"id":"baby-citizenship","t":"people","q":"Why does a newborn baby automatically belong to a country?"},{"id":"baby-grammar-mistakes","t":"people","q":"Why do little kids say things like 'I goed to the park' or 'two mouses'?"},{"id":"baby-hear-sounds","t":"people","q":"Why can tiny babies hear sound differences that grown-ups often can't?"},{"id":"baby-mama-papa","t":"people","q":"Why is the word for 'mum' so similar in so many unrelated languages?"},{"id":"baby-teeth-fall-out","t":"people","q":"Why do baby teeth fall out and get replaced by adult ones?"},{"id":"backpack-two-straps","t":"people","q":"Why are backpacks meant to be worn on both shoulders instead of slung over just one?"},{"id":"beliefs","t":"people","q":"Why do people believe different things?"},{"id":"belong-to-friends-family","t":"people","q":"Why can you feel like you belong to a friend's family too, sometimes?"},{"id":"berlin-conference-africa","t":"people","q":"Why do so many African countries have perfectly straight-line borders?"},{"id":"bill-becomes-law","t":"people","q":"Why does turning an idea into an actual law usually take months of debate and multiple votes?"},{"id":"binary-computers","t":"people","q":"Why do computers count using only two digits, 0 and 1?"},{"id":"birth-order-myth","t":"people","q":"Why doesn't being the eldest, middle or youngest child actually decide your personality?"},{"id":"birthday-paradox","t":"people","q":"Why do just 23 people in a room have better-than-even odds that two share a birthday?"},{"id":"birthdays","t":"people","q":"Why do we celebrate birthdays?"},{"id":"blended-families-steps","t":"people","q":"Why do blended families end up with step-siblings and half-siblings?"},{"id":"blowing-candles-wish","t":"people","q":"Why do we make a wish and blow out candles?"},{"id":"bonfire-night","t":"people","q":"Why do people light bonfires and set off fireworks on Bonfire Night?"},{"id":"books","t":"people","q":"Why do we still read books when we have screens?"},{"id":"border-checkpoint","t":"people","q":"Why do you have to stop and show ID at some borders but not others?"},{"id":"borders","t":"people","q":"Why do countries have borders?"},{"id":"boredom","t":"people","q":"Why do we get bored?"},{"id":"bouba-kiki","t":"people","q":"Why does the made-up word 'bouba' sound round and 'kiki' sound spiky?"},{"id":"braille-dots","t":"people","q":"Why is Braille made of raised dots instead of raised versions of ordinary letters?"},{"id":"brain-no-reading-circuit","t":"people","q":"Why doesn't your brain come with a built-in circuit for reading, the way it has one for talking?"},{"id":"bribery-undermines-rules","t":"people","q":"Why is bribing an official illegal even when nobody involved feels directly harmed by it?"},{"id":"bubble-sheets","t":"people","q":"Why do standardised tests ask you to fill in little bubbles with a pencil instead of just writing the answer?"},{"id":"calculators-banned-exams","t":"people","q":"Why do some maths exams still ban calculators when almost every student carries one in their pocket?"},{"id":"candidate-age-minimum","t":"people","q":"Why must some leaders be older than the age at which they're allowed to vote for one?"},{"id":"candles-for-dead","t":"people","q":"Why do people light candles to remember someone who died?"},{"id":"capital-city-why","t":"people","q":"Why does every country need one official capital city?"},{"id":"capital-i","t":"people","q":"Why is \"I\" always written as a capital letter no matter where it sits in a sentence?"},{"id":"capital-punishment-decline","t":"people","q":"Why have most countries stopped using the death penalty, even for very serious crimes?"},{"id":"carnival-before-lent","t":"people","q":"Why do carnivals happen right before periods of fasting?"},{"id":"chalk-squeak","t":"people","q":"Why does chalk sometimes make an ear-splitting squeal on a chalkboard, even though most of the time it doesn't?"},{"id":"chalkboard-green","t":"people","q":"Why are most \"blackboards\" in classrooms today actually a dark green colour, not black?"},{"id":"childhood-long-humans","t":"people","q":"Why does childhood last so much longer for humans than for other animals?"},{"id":"chinese-characters","t":"people","q":"Why does Chinese writing use thousands of symbols instead of 26 letters?"},{"id":"chores-grow-with-age","t":"people","q":"Why do the chores you're given change as you grow up?"},{"id":"christmas-date-25-dec","t":"people","q":"Why is Christmas celebrated on 25 December when nobody recorded the actual date?"},{"id":"christmas-tree","t":"people","q":"Why do people bring an evergreen tree indoors in midwinter?"},{"id":"chunking-memory","t":"people","q":"Why are phone numbers broken into small groups instead of written as one long string of digits?"},{"id":"cicada-primes","t":"people","q":"Why do some cicadas wait exactly 13 or 17 years before hatching?"},{"id":"citizens-assembly-modern","t":"people","q":"Why did one country hand a tricky political question to a hundred ordinary strangers chosen by lottery?"},{"id":"clock-gift-taboo","t":"people","q":"Why do some people avoid giving a clock as a gift?"},{"id":"clock-iiii","t":"people","q":"Why do some clock faces show four o'clock as IIII instead of IV?"},{"id":"coalition-government","t":"people","q":"Why do some countries end up governed by several parties glued together instead of just one?"},{"id":"collecting","t":"people","q":"Why do people collect things?"},{"id":"colour-words-vary","t":"people","q":"Why do some languages use one word for both blue and green?"},{"id":"coming-of-age-ceremony","t":"people","q":"Why do many cultures mark reaching a certain age with a special ceremony?"},{"id":"compulsory-voting-countries","t":"people","q":"Why do only a handful of countries actually fine you for skipping an election?"},{"id":"confetti-throw","t":"people","q":"Why do people throw confetti at celebrations?"},{"id":"constitution-rules-for-rules","t":"people","q":"Why do some countries have a special document that even ordinary laws aren't allowed to break?"},{"id":"constitutional-monarchy-vs-elected","t":"people","q":"Why do some countries have both a king or queen and an elected leader at the same time?"},{"id":"context-dependent-memory","t":"people","q":"Why can you sometimes remember something better in the room where you first learned it than anywhere else?"},{"id":"correlation-causation","t":"people","q":"Why doesn't one thing causing another follow just because the two happen together?"},{"id":"count-tens","t":"people","q":"Why do we count in groups of ten?"},{"id":"country-name-different","t":"people","q":"Why is Germany called something completely different in its own language?"},{"id":"country-recognition","t":"people","q":"Why isn't Taiwan universally recognised as a country by every other nation?"},{"id":"courts-have-appeals","t":"people","q":"Why can someone found guilty in court sometimes get a second court to look at their case?"},{"id":"cousins-dna","t":"people","q":"Why do cousins share less DNA than siblings do?"},{"id":"crying-not-weak","t":"people","q":"Why is it a myth that crying means someone is weak?"},{"id":"curfew-laws","t":"people","q":"Why do some towns set a curfew that only applies to people under a certain age?"},{"id":"cursive-purpose","t":"people","q":"Why did people join letters together into cursive writing at all?"},{"id":"cut-and-choose-fair-division","t":"people","q":"Why does \"you cut, I'll choose\" actually guarantee a fair split between two people?"},{"id":"dead-language","t":"people","q":"Why do some languages disappear completely?"},{"id":"desirable-difficulty","t":"people","q":"Why can making a mistake while you're learning something actually help you remember it better?"},{"id":"detention-punishment","t":"people","q":"Why does staying back after school work as a punishment for breaking classroom rules?"},{"id":"dialects-vocab","t":"people","q":"Why do people in different regions use completely different words for the same everyday thing?"},{"id":"diplomatic-immunity","t":"people","q":"Why can't a foreign diplomat usually be arrested by local police, even for breaking a local law?"},{"id":"divorce-still-your-parent","t":"people","q":"Why does a parent stay your parent even after they separate from your other parent?"},{"id":"diwali-lights","t":"people","q":"Why do lights play such a big role in Diwali?"},{"id":"dna-half-parents","t":"people","q":"Why do you only get half your DNA from each parent, not more?"},{"id":"dna-tests-relatives","t":"people","q":"Why do people now use DNA tests to find long-lost relatives?"},{"id":"donkey-vote-ballot-order","t":"people","q":"Why is the order candidates appear on a ballot paper sometimes drawn at random?"},{"id":"dot-on-i","t":"people","q":"Why does a lowercase i have a dot sitting above it?"},{"id":"double-jeopardy","t":"people","q":"Why can't someone be put on trial twice for the exact same crime after being found not guilty?"},{"id":"double-negative","t":"people","q":"Why isn't saying 'I don't want none' actually bad grammar?"},{"id":"drum-language","t":"people","q":"Why can West African talking drums 'speak' whole sentences?"},{"id":"dual-citizenship","t":"people","q":"Why can some people hold citizenship in two countries at once?"},{"id":"dyslexia-language","t":"people","q":"Why can the same person's dyslexia look milder in one language than another?"},{"id":"easter-date-moves","t":"people","q":"Why does the date of Easter move around every year?"},{"id":"easter-eggs","t":"people","q":"Why are eggs linked to spring festivals?"},{"id":"egyptian-fractions","t":"people","q":"Why did ancient Egyptians write almost every fraction using only a 1 on top?"},{"id":"eid-feast","t":"people","q":"Why does a feast follow a month of fasting at Eid?"},{"id":"election-day-tuesday","t":"people","q":"Why does one country always hold its national election on a Tuesday, of all days?"},{"id":"election-day-weekend","t":"people","q":"Why do some countries deliberately hold their elections on a Saturday instead of a weekday?"},{"id":"electoral-college-basic","t":"people","q":"Why can a leader be chosen by votes that aren't just a straight nationwide count?"},{"id":"embarrassed","t":"people","q":"Why do we get embarrassed?"},{"id":"emoji-culture","t":"people","q":"Why don't emoji mean the same thing to everyone, even though they're just pictures?"},{"id":"emoji-no-grammar","t":"people","q":"Why can't a string of emoji fully replace an ordinary written sentence?"},{"id":"equal-regional-representation","t":"people","q":"Why does a small region sometimes get exactly the same say in national government as a huge one?"},{"id":"eraser-history","t":"people","q":"Why did people use lumps of bread to rub out pencil marks before rubber erasers existed?"},{"id":"exam-silence-rule","t":"people","q":"Why do exams require complete silence, when talking things through usually helps you think?"},{"id":"exit-poll-vs-result","t":"people","q":"Why can television announce a likely election winner hours before all the votes are counted?"},{"id":"extradition","t":"people","q":"Why can someone accused of a crime in one country be sent back there from a different country?"},{"id":"eyewitness-unreliable","t":"people","q":"Why do courts today treat a confident eyewitness's memory with more caution than they once did?"},{"id":"fairness-not-sameness","t":"people","q":"Why doesn't treating everyone exactly the same always count as being fair?"},{"id":"families","t":"people","q":"Why do we live in families?"},{"id":"families-argue-makeup","t":"people","q":"Why do families argue, and how do they make up afterwards?"},{"id":"family-not-about-looks","t":"people","q":"Why doesn't a family need to look alike to be a real family?"},{"id":"family-photo-albums","t":"people","q":"Why do families keep old photo albums instead of just deleting old photos?"},{"id":"family-recipe-passed-down","t":"people","q":"Why do families pass certain recipes down for generations?"},{"id":"family-reunions","t":"people","q":"Why do family reunions bring together relatives who barely know each other?"},{"id":"family-rules-bedtime","t":"people","q":"Why do families make rules like bedtimes at all?"},{"id":"family-tree-branches","t":"people","q":"Why does a family tree branch out wider the further back you go?"},{"id":"family-word-different-cultures","t":"people","q":"Why does the word 'family' mean something different in every culture?"},{"id":"fashion-changes","t":"people","q":"Why does fashion keep changing?"},{"id":"finders-keepers-myth","t":"people","q":"Why isn't \"finders keepers\" actually true if you find something valuable that someone else lost?"},{"id":"finger-twelve","t":"people","q":"Why did some traders count to twelve using just one thumb?"},{"id":"finland-income-fines","t":"people","q":"Why do some countries charge a speeding fine based on how much money the driver earns?"},{"id":"fire-drills","t":"people","q":"Why do schools practise fire drills regularly instead of just teaching the exit routes once?"},{"id":"firecrackers-scare-away","t":"people","q":"Why do firecrackers make such a racket at some festivals?"},{"id":"fireworks-boom","t":"people","q":"Why do fireworks make such a loud bang?"},{"id":"fireworks-colours","t":"people","q":"Why do fireworks burst into different colours?"},{"id":"fireworks-invented-china","t":"people","q":"Why were fireworks invented in China over a thousand years ago?"},{"id":"first-past-post","t":"people","q":"Why does simply having the most votes sometimes win, with no majority needed at all?"},{"id":"flag-crescent-star","t":"people","q":"Why do so many flags of Muslim-majority countries feature a crescent moon?"},{"id":"flag-half-mast","t":"people","q":"Why do countries lower their flags to half-mast when someone important dies?"},{"id":"flag-of-convenience","t":"people","q":"Why do so many cargo ships fly the flag of a country they've never even visited?"},{"id":"flag-pan-african-colors","t":"people","q":"Why do so many African flags share the same handful of colours?"},{"id":"flag-raising-ceremony","t":"people","q":"Why do ceremonies often involve raising a flag?"},{"id":"flags","t":"people","q":"Why do countries have flags?"},{"id":"food-borrowed","t":"people","q":"Why are so many food words in English borrowed from French?"},{"id":"forgetting-curve","t":"people","q":"Why do you forget most of a new fact within a day unless you review it?"},{"id":"foster-families","t":"people","q":"Why do some kids live with a foster family instead of their birth parents?"},{"id":"fractal-fern","t":"people","q":"Why does a fern frond look like it's made of smaller copies of itself?"},{"id":"fraction-common-denominator","t":"people","q":"Why do you need a common denominator before you can add two fractions?"},{"id":"friend-adult-fewer-best","t":"people","q":"Why do adults usually stop talking about having one \"best friend\" the way kids do?"},{"id":"friend-apology-specific-works","t":"people","q":"Why does \"sorry for what I did\" work so much better than just \"sorry\"?"},{"id":"friend-argument-strengthen","t":"people","q":"Why can a big argument with a friend sometimes make the friendship stronger?"},{"id":"friend-broken-trust-quick","t":"people","q":"Why does one lie sometimes undo years of a friend trusting you?"},{"id":"friend-change-with-age","t":"people","q":"Why are five-year-olds happy to call almost anyone a friend, while teenagers are so much pickier?"},{"id":"friend-clique-excludes","t":"people","q":"Why do tight friend groups sometimes end up leaving other people out without really deciding to?"},{"id":"friend-confide-not-family","t":"people","q":"Why do people sometimes tell a friend something they'd never tell their own family?"},{"id":"friend-decades-long-why","t":"people","q":"Why do some childhood friendships last a whole lifetime while others don't survive one house move?"},{"id":"friend-different-ages-help","t":"people","q":"Why can a friendship with someone much older or younger teach you things your same-age friends can't?"},{"id":"friend-different-friends-different-things","t":"people","q":"Why might you have one friend for video games and a completely different one for talking about problems?"},{"id":"friend-drift-apart-no-fight","t":"people","q":"Why can two friends drift apart without ever actually falling out?"},{"id":"friend-eye-contact-bond","t":"people","q":"Why does looking someone in the eye while talking make you feel closer to them?"},{"id":"friend-fade-without-fault","t":"people","q":"Why can a friendship quietly fade away even when nobody has done anything wrong?"},{"id":"friend-favour-feels-good","t":"people","q":"Why does doing a friend a favour feel almost as good as getting one?"},{"id":"friend-fight-most-with-best","t":"people","q":"Why do you sometimes argue more with your best friend than with people you barely know?"},{"id":"friend-finish-sentences","t":"people","q":"Why can close friends often guess what the other is about to say?"},{"id":"friend-first-move-scary","t":"people","q":"Why does going up to someone new and asking to be friends feel so frightening?"},{"id":"friend-forgive-repair","t":"people","q":"Why does saying sorry properly often make a friendship stronger than it was before the fight?"},{"id":"friend-frenemy-confusing","t":"people","q":"Why can a \"frenemy\" feel more stressful than someone who's just plain mean?"},{"id":"friend-gossip-social-glue","t":"people","q":"Why does gossiping about other people play a real part in how friendships form?"},{"id":"friend-greeting-customs-vary","t":"people","q":"Why do friends greet each other so differently around the world — handshake, hug, cheek kiss, nose rub?"},{"id":"friend-group-dress-alike","t":"people","q":"Why do friend groups often end up dressing or talking alike without ever planning it?"},{"id":"friend-group-size-culture-vary","t":"people","q":"Why do some cultures raise kids to have one or two best friends while others expect a big friend group?"},{"id":"friend-hard-to-end-bad","t":"people","q":"Why is it so hard to walk away from a friendship even when it's making you unhappy?"},{"id":"friend-harder-to-make-adult","t":"people","q":"Why is it so much harder to make close friends once you're grown up?"},{"id":"friend-imaginary-normal","t":"people","q":"Why do so many young kids have an imaginary friend?"},{"id":"friend-inside-jokes-bond","t":"people","q":"Why do inside jokes make outsiders feel left out but make friends feel closer?"},{"id":"friend-jealous-new-friend","t":"people","q":"Why can it sting when your best friend makes another close friend?"},{"id":"friend-keeping-up-effort","t":"people","q":"Why do even great friendships need regular contact to stay strong?"},{"id":"friend-laugh-together-bond","t":"people","q":"Why does laughing at the same joke with a friend feel so much better than laughing alone?"},{"id":"friend-loneliness-body-harm","t":"people","q":"Why can feeling lonely for a long time actually make your body less healthy?"},{"id":"friend-mimic-mannerisms","t":"people","q":"Why do you start picking up a friend's expressions and sayings without meaning to?"},{"id":"friend-moving-away-hurts","t":"people","q":"Why does a friend moving to a new city feel a bit like a real loss?"},{"id":"friend-new-school-hard","t":"people","q":"Why does changing schools make it so hard to keep up with old friends?"},{"id":"friend-online-feels-real","t":"people","q":"Why can a friend you've only ever texted or gamed with feel like a real friend?"},{"id":"friend-peer-pressure-strong","t":"people","q":"Why do friends have more power to talk you into something than a stranger does?"},{"id":"friend-proximity-mere-exposure","t":"people","q":"Why do you end up friends with whoever sits next to you more than anyone else?"},{"id":"friend-quality-over-quantity","t":"people","q":"Why is having two or three really close friends often better than having fifty okay ones?"},{"id":"friend-secrets-closeness","t":"people","q":"Why does telling a friend a secret make you feel closer to them?"},{"id":"friend-shared-enemy-bond","t":"people","q":"Why does having someone to dislike together, like a strict teacher, sometimes bring a group closer?"},{"id":"friend-shared-hardship-bond","t":"people","q":"Why do people who go through something hard together often become close friends fast?"},{"id":"friend-similarity-not-opposites","t":"people","q":"Why do most friends turn out to like similar things instead of being opposites?"},{"id":"friend-text-reply-hurts","t":"people","q":"Why does it sting when a friend takes ages to reply to a message?"},{"id":"friend-toddler-parallel-play","t":"people","q":"Why do toddlers play next to each other instead of together, and still call it playing with a friend?"},{"id":"friend-trust-built-slowly","t":"people","q":"Why does trust between friends take so long to build but so little to break?"},{"id":"friends","t":"people","q":"Why do we have friends?"},{"id":"full-stop-origin","t":"people","q":"Why do we mark the end of a sentence with a single dot?"},{"id":"gambler-fallacy","t":"people","q":"Why doesn't a coin that's landed heads five times in a row owe you a tails next?"},{"id":"gerrymander-name","t":"people","q":"Why is drawing an oddly shaped voting district named after a salamander?"},{"id":"gift-giving-winter","t":"people","q":"Why do people exchange gifts at winter holidays?"},{"id":"googol-atoms","t":"people","q":"Why is a googol bigger than the number of atoms in the universe?"},{"id":"graduation-cap-toss","t":"people","q":"Why do graduates throw their caps in the air?"},{"id":"grandparents-know-things","t":"people","q":"Why do grandparents often know things your parents don't?"},{"id":"grandparents-live-with","t":"people","q":"Why do some families live with grandparents under one roof?"},{"id":"graph-axis-trick","t":"people","q":"Why can chopping the bottom off a bar graph make a tiny difference look enormous?"},{"id":"great-wall-purpose","t":"people","q":"Why did ancient China build a wall thousands of kilometres long?"},{"id":"greeting-cards-history","t":"people","q":"Why do people send cards for celebrations?"},{"id":"group-work-assigned","t":"people","q":"Why do teachers put students into groups to work on problems together instead of everyone working alone?"},{"id":"growing-kids-eat-more","t":"people","q":"Why do growing kids suddenly eat so much more during a growth spurt?"},{"id":"growth-chart-percentiles","t":"people","q":"Why do growth charts use percentiles instead of one 'right' height for your age?"},{"id":"growth-mindset-praise","t":"people","q":"Why does telling a kid \"you worked really hard\" help them more than telling them \"you're so smart\"?"},{"id":"growth-spurts-bursts","t":"people","q":"Why do you grow taller in sudden bursts instead of smoothly all year?"},{"id":"hadrians-wall","t":"people","q":"Why did the Romans build a wall clear across the north of England?"},{"id":"halloween-costumes","t":"people","q":"Why do people dress up in costumes for Halloween?"},{"id":"hammurabi-first-laws","t":"people","q":"Why did one ancient king carve his entire set of laws into a giant stone pillar?"},{"id":"handshake","t":"people","q":"Why do people shake hands?"},{"id":"handwriting-memory","t":"people","q":"Why do notes you write by hand often stick in your memory better than typed ones?"},{"id":"hanging-chad-ballot","t":"people","q":"Why did some old voting machines punch tiny paper squares instead of using a pen?"},{"id":"hangul-mouth","t":"people","q":"Why do some Korean letters look like the shape your mouth makes?"},{"id":"hanukkah-menorah","t":"people","q":"Why does a Hanukkah menorah have nine branches instead of seven?"},{"id":"harvest-festival","t":"people","q":"Why do so many cultures hold a festival at harvest time?"},{"id":"hieroglyph-rebus","t":"people","q":"Why did Egyptian hieroglyphs use picture-sound puzzles instead of just drawing pictures?"},{"id":"highlighting-ineffective","t":"people","q":"Why does highlighting a textbook rarely help you remember what's in it?"},{"id":"hilbert-hotel","t":"people","q":"Why can a hotel with an infinite number of rooms always fit in one more guest?"},{"id":"holi-colours","t":"people","q":"Why do people throw coloured powder at each other during Holi?"},{"id":"homework-purpose","t":"people","q":"Why do teachers give homework instead of just fitting everything into the school day?"},{"id":"honeycomb-hexagon","t":"people","q":"Why is a hexagon the mathematically best shape for a honeycomb cell?"},{"id":"hour-sixty","t":"people","q":"Why does an hour have 60 minutes instead of 100?"},{"id":"human-babies-need-care","t":"people","q":"Why do human babies need so much more care than baby animals do?"},{"id":"hung-parliament","t":"people","q":"Why does an election sometimes leave nobody able to say clearly who won?"},{"id":"hyphenated-surnames","t":"people","q":"Why do some married couples hyphenate their surnames together?"},{"id":"ignorance-not-excuse","t":"people","q":"Why doesn't saying \"I didn't know that was against the law\" get someone out of trouble?"},{"id":"impeachment-vs-election","t":"people","q":"Why is removing a leader for wrongdoing a completely different process from simply voting them out?"},{"id":"indelible-ink-finger","t":"people","q":"Why do election workers sometimes paint a purple mark on someone's finger after they vote?"},{"id":"independence-day-fireworks","t":"people","q":"Why do fireworks often mark the anniversary of a country's independence?"},{"id":"india-pakistan-partition","t":"people","q":"Why did British India split into India and Pakistan in 1947?"},{"id":"indus-script","t":"people","q":"Why can't anyone read the writing of the Indus Valley, one of the world's first cities?"},{"id":"infinity-no-end","t":"people","q":"Why can you never actually finish counting to infinity?"},{"id":"infinity-sizes","t":"people","q":"Why are some infinities bigger than other infinities?"},{"id":"innocent-until-proven-guilty","t":"people","q":"Why does the law assume someone is innocent until it's actually proven they're guilty?"},{"id":"intent-matters-law","t":"people","q":"Why does the law treat hurting someone by accident so differently from hurting them on purpose?"},{"id":"interleaving-practice","t":"people","q":"Why does mixing up different kinds of maths problems while studying work better than doing twenty of the same type in a row?"},{"id":"international-adoption","t":"people","q":"Why can a family adopt a child from a completely different country?"},{"id":"ireland-split","t":"people","q":"Why is the island of Ireland divided between two different countries?"},{"id":"iron-gall-ink","t":"people","q":"Why does the ink in some very old documents eat holes right through the paper?"},{"id":"jack-o-lantern","t":"people","q":"Why do carved pumpkins get a candle inside?"},{"id":"japan-three-scripts","t":"people","q":"Why does Japanese mix three completely different alphabets in one sentence?"},{"id":"jerusalem-capital-dispute","t":"people","q":"Why do different countries disagree about which city is Israel's real capital?"},{"id":"job-pay-differs","t":"people","q":"Why do some jobs pay a lot more than others?"},{"id":"jobs","t":"people","q":"Why do grown-ups have to go to work?"},{"id":"judges-recuse","t":"people","q":"Why does a judge sometimes step aside from a case they were originally assigned to hear?"},{"id":"judges-wear-robes","t":"people","q":"Why do judges wear long black robes instead of ordinary clothes in court?"},{"id":"jumbled-letters","t":"people","q":"Why can you sometimes still read a wrod even wehn the mddile letters are jumbled?"},{"id":"jury-selection-random","t":"people","q":"Why are jurors picked essentially at random from the public instead of chosen for their expertise?"},{"id":"jury-twelve","t":"people","q":"Why do so many countries put exactly twelve ordinary people on a jury?"},{"id":"jus-soli-sanguinis","t":"people","q":"Why does being born in one country make you a citizen there, while in another it depends on your parents?"},{"id":"juvenile-court-separate","t":"people","q":"Why do many countries run separate courts specifically for children accused of crimes?"},{"id":"kaliningrad-exclave","t":"people","q":"Why is part of Russia cut off from the rest of Russia by other countries?"},{"id":"kids-different-rules","t":"people","q":"Why do kids get different legal rules than adults, like not being able to sign a binding contract?"},{"id":"kids-flip-letters","t":"people","q":"Why do young kids so often write b instead of d, or write whole letters backwards?"},{"id":"kindergarten-age-five","t":"people","q":"Why do most children start formal schooling around age five or six rather than earlier or later?"},{"id":"korea-dmz","t":"people","q":"Why is there a strip of land between the two Koreas where almost nobody is allowed to go?"},{"id":"landlocked-countries","t":"people","q":"Why do some countries have no coastline at all?"},{"id":"lang-change-why","t":"people","q":"Why do languages keep changing even though everyone already understands each other?"},{"id":"lang-split","t":"people","q":"Why did one language, Latin, turn into French, Spanish and Italian?"},{"id":"languages","t":"people","q":"Why are there different languages?"},{"id":"latin-dead-but-used","t":"people","q":"Why is Latin called a 'dead' language when doctors still use Latin words?"},{"id":"laugh","t":"people","q":"Why do people laugh?"},{"id":"laws-written-not-remembered","t":"people","q":"Why do important laws get written down instead of just being remembered and passed on?"},{"id":"leap-day-birthday","t":"people","q":"Why do people born on 29 February only get a 'real' birthday every four years?"},{"id":"left-handed","t":"people","q":"Why are some people left-handed?"},{"id":"left-handed-desks","t":"people","q":"Why can an ordinary school desk with an attached arm be awkward for a left-handed student to write at?"},{"id":"left-handed-smudge","t":"people","q":"Why do left-handed writers often smudge the words they've just written?"},{"id":"legal-systems-differ-worldwide","t":"people","q":"Why do courts in different countries decide cases in such different ways?"},{"id":"lesotho-enclave","t":"people","q":"Why is Lesotho a whole country completely surrounded by South Africa?"},{"id":"letter-a-ox","t":"people","q":"Why does the letter A look nothing like the sound it makes?"},{"id":"letter-grades","t":"people","q":"Why do school grades use letters like A, B and C instead of just a plain score out of a hundred?"},{"id":"library-dewey","t":"people","q":"Why does every library book have a number printed on its spine?"},{"id":"lie-detector-not-proof","t":"people","q":"Why can't a lie detector test alone prove someone is guilty in most courts?"},{"id":"lion-dance","t":"people","q":"Why do lion dances appear at Lunar New Year celebrations?"},{"id":"loanwords-general","t":"people","q":"Why does English have so many words borrowed from other languages?"},{"id":"locker-combination","t":"people","q":"Why can spinning a combination lock's dial to just three numbers, in the right order, open it without a key?"},{"id":"long-division-taught","t":"people","q":"Why do schools still teach long division step by step when a calculator gives the answer instantly?"},{"id":"look-like-grandparent","t":"people","q":"Why do you sometimes look more like a grandparent than either of your parents?"},{"id":"lose-citizenship","t":"people","q":"Why can a person lose their citizenship?"},{"id":"lunar-new-year-red","t":"people","q":"Why is red the colour of Lunar New Year?"},{"id":"lying","t":"people","q":"Why do people tell lies?"},{"id":"magna-carta-king","t":"people","q":"Why was it such a big deal when English nobles forced a king to sign a document in 1215?"},{"id":"majority-vs-plurality","t":"people","q":"Why can someone win an election without getting more votes than everyone else combined?"},{"id":"manners","t":"people","q":"Why do we have manners?"},{"id":"maps-disagree-borders","t":"people","q":"Why do maps of the same region sometimes show a country's border differently depending on which country made the map?"},{"id":"maths-anxiety","t":"people","q":"Why does feeling anxious about a maths problem make it harder to solve, even if you know how?"},{"id":"maths-everywhere","t":"people","q":"Why is maths the same in every country?"},{"id":"maypole-dance","t":"people","q":"Why do people dance around a maypole in spring?"},{"id":"micronation-tuvalu","t":"people","q":"Why does a tiny country like Tuvalu get the same vote at the UN as a giant one like China?"},{"id":"million-vs-billion","t":"people","q":"Why does \"a million seconds\" feel similar to \"a billion seconds\" when they're wildly different?"},{"id":"misleading-average","t":"people","q":"Why can the \"average\" wage on a street be far higher than almost everyone actually earns?"},{"id":"mistletoe-kiss","t":"people","q":"Why do people kiss under mistletoe?"},{"id":"mnemonic-devices","t":"people","q":"Why do silly rhymes and made-up acronyms help you remember lists that would otherwise slip out of your head?"},{"id":"monaco-density","t":"people","q":"Why is Monaco so packed with people despite being one of the smallest countries on Earth?"},{"id":"money","t":"people","q":"Why is money worth anything?"},{"id":"moving-house-hard","t":"people","q":"Why does moving house feel hard even when the new house is nicer?"},{"id":"multigenerational-households","t":"people","q":"Why are households with grandparents, parents and kids all together common in many countries?"},{"id":"multilingual-families","t":"people","q":"Why do some families speak more than one language at home?"},{"id":"music-feels","t":"people","q":"Why does music make you feel things?"},{"id":"names","t":"people","q":"Why do we have names?"},{"id":"nautilus-not-golden","t":"people","q":"Why isn't the nautilus shell's spiral actually built on the famous \"golden ratio\"?"},{"id":"negative-false","t":"people","q":"Why were negative numbers once dismissed by mathematicians as \"false\"?"},{"id":"negative-times-negative","t":"people","q":"Why does multiplying two negative numbers give a positive answer?"},{"id":"new-words-blend","t":"people","q":"Why are words like 'brunch' and 'smog' actually two words squashed together?"},{"id":"new-words-brand","t":"people","q":"Why did 'trampoline' and 'escalator' used to be brand names?"},{"id":"new-year-different-dates","t":"people","q":"Why doesn't every culture celebrate New Year on the same date?"},{"id":"new-year-midnight","t":"people","q":"Why do New Year celebrations happen right at midnight?"},{"id":"no-confidence-vote","t":"people","q":"Why can a country's leader lose their job without any election happening?"},{"id":"no-mans-land","t":"people","q":"Why is there sometimes a strip of empty ground that belongs to no country at all?"},{"id":"no-retroactive-laws","t":"people","q":"Why can't a government punish someone for doing something legal when they actually did it?"},{"id":"no-spaces","t":"people","q":"Why didn't ancient books have spaces between words?"},{"id":"not-a-maths-person","t":"people","q":"Why isn't \"I'm not a maths person\" actually true of anyone?"},{"id":"note-taking-encoding","t":"people","q":"Why can taking notes during a lesson help you remember it even if you never read the notes again afterwards?"},{"id":"ok-global","t":"people","q":"Why is 'OK' understood in almost every country on Earth?"},{"id":"old-book-smell","t":"people","q":"Why do old books have that particular sweet, warm smell?"},{"id":"older-sibling-third-parent","t":"people","q":"Why do older siblings sometimes act like a third parent?"},{"id":"olympics-flag-march","t":"people","q":"Why do Olympic athletes walk out behind their own country's flag?"},{"id":"ough-different","t":"people","q":"Why are 'through', 'though', 'tough' and 'cough' all spelled the same but said differently?"},{"id":"overseas-voting-embassy","t":"people","q":"Why can someone vote in their home country's election from thousands of kilometres away?"},{"id":"papal-conclave-vote","t":"people","q":"Why does smoke rising from a chimney announce who has been chosen to lead the Catholic Church?"},{"id":"paper-no-glue","t":"people","q":"Why does paper hold together without any glue in it at all?"},{"id":"passport-crossing","t":"people","q":"Why do you need a passport to cross into another country?"},{"id":"pencil-hexagon","t":"people","q":"Why are most wooden pencils shaped with six flat sides instead of just being round?"},{"id":"pencil-lead-myth","t":"people","q":"Why do we call it a \"lead\" pencil when there's no lead inside it at all?"},{"id":"pencil-yellow","t":"people","q":"Why are so many pencils painted the exact same shade of yellow?"},{"id":"petals-fibonacci","t":"people","q":"Why do many flowers have petal counts that are Fibonacci numbers, like 3, 5, 8 or 13?"},{"id":"phone-nearby-focus","t":"people","q":"Why can having your phone sitting on the desk make you focus worse, even if it's switched off and you never touch it?"},{"id":"phonics-vs-guessing","t":"people","q":"Why do children usually learn to read faster by sounding out words than by guessing them?"},{"id":"pi-never-repeats","t":"people","q":"Why do the digits of pi never settle into a repeating pattern?"},{"id":"pi-same-every-circle","t":"people","q":"Why is pi the same number for every circle that has ever existed?"},{"id":"pi-toothpicks","t":"people","q":"Why can dropping toothpicks onto a lined floor help you estimate pi?"},{"id":"pinata-hitting","t":"people","q":"Why do some celebrations involve hitting a pinata?"},{"id":"plagiarism-citations","t":"people","q":"Why is copying someone else's work and not saying where it came from considered cheating, even if the copied part is true?"},{"id":"plea-bargain-common","t":"people","q":"Why do most criminal cases never actually go to a full trial?"},{"id":"plural-voting-history","t":"people","q":"Why did some people in Britain once get to vote in the very same election twice?"},{"id":"pm-not-directly-elected","t":"people","q":"Why do some countries never let citizens vote directly for their top leader?"},{"id":"pocket-money-responsibility","t":"people","q":"Why do kids often get pocket money instead of just being given things?"},{"id":"police-origin","t":"people","q":"Why do most cities have a police force instead of leaving law enforcement to whoever's nearby?"},{"id":"postal-voting","t":"people","q":"Why can someone vote in an election without ever visiting a polling place?"},{"id":"powers-of-ten","t":"people","q":"Why do scientists write enormous numbers as powers of ten instead of writing out all the zeros?"},{"id":"prairie-dog-calls","t":"people","q":"Why do prairie dogs use different alarm calls for different predators?"},{"id":"preferential-voting","t":"people","q":"Why do some ballots ask you to number every candidate instead of picking just one?"},{"id":"primacy-recency","t":"people","q":"Why do you usually remember the first and last things on a list better than the ones in the middle?"},{"id":"prime-never-stop","t":"people","q":"Why do mathematicians know prime numbers never run out?"},{"id":"prime-not-one","t":"people","q":"Why isn't the number 1 counted as a prime number?"},{"id":"promise-becomes-contract","t":"people","q":"Why does a written contract count for more than someone just promising you something out loud?"},{"id":"proportional-representation","t":"people","q":"Why do some parliaments end up with a dozen small parties, instead of just two big ones?"},{"id":"protege-effect","t":"people","q":"Why does explaining something you've just learned to someone else help you understand it yourself?"},{"id":"protractor-shape","t":"people","q":"Why are most protractors shaped like a half-circle instead of a full circle?"},{"id":"punishment-fits-crime","t":"people","q":"Why doesn't stealing a chocolate bar get the same punishment as stealing a car?"},{"id":"question-mark-shape","t":"people","q":"Why does the question mark have that particular curled shape?"},{"id":"quipu-knots","t":"people","q":"Why did Inca record keepers tie knots in string instead of writing numbers?"},{"id":"quota-seats-women","t":"people","q":"Why do some parliaments guarantee a fixed number of seats for women before a single vote is even counted?"},{"id":"raise-hand-classroom","t":"people","q":"Why did raising your hand before speaking become the standard rule in classrooms?"},{"id":"ramadan-fasting","t":"people","q":"Why do people fast from dawn to dusk during Ramadan?"},{"id":"recall-election","t":"people","q":"Why can voters sometimes remove a leader partway through their term without waiting for the next election?"},{"id":"recess-needed","t":"people","q":"Why do kids need a recess break between lessons instead of just working straight through the day?"},{"id":"recount-close-election","t":"people","q":"Why does a really close election sometimes get counted all over again from scratch?"},{"id":"red-envelopes","t":"people","q":"Why do people give money in red envelopes at Lunar New Year?"},{"id":"redistribution-boundaries","t":"people","q":"Why do the borders of a voting district get redrawn every so often, even without a scandal?"},{"id":"referees-needed","t":"people","q":"Why do sports need a referee at all if every player already knows the rules?"},{"id":"referendum-vs-election","t":"people","q":"Why does voting on a law feel so different from voting for a person?"},{"id":"restorative-justice","t":"people","q":"Why do some justice systems have an offender sit down and talk directly with the person they harmed?"},{"id":"retrieval-practice","t":"people","q":"Why does testing yourself on facts help you remember them better than reading them over again?"},{"id":"right-to-lawyer","t":"people","q":"Why does even someone who's clearly guilty still get a lawyer to defend them in court?"},{"id":"river-border-shift","t":"people","q":"Why can a country's border quietly move when the river marking it changes course?"},{"id":"roman-no-zero","t":"people","q":"Why do Roman numerals have no way to write zero at all?"},{"id":"rongorongo","t":"people","q":"Why has nobody ever fully deciphered the Rongorongo script from Easter Island?"},{"id":"rosetta-stone","t":"people","q":"Why did one particular carved stone finally unlock Egyptian hieroglyphs?"},{"id":"ruler-two-scales","t":"people","q":"Why do many rulers have centimetres marked along one edge and inches along the other?"},{"id":"rules-change-with-age","t":"people","q":"Why do family rules change as you get older?"},{"id":"rules-laws","t":"people","q":"Why do we have rules?"},{"id":"russia-time-zones","t":"people","q":"Why does one single country, Russia, stretch across 11 different time zones?"},{"id":"san-marino-oldest","t":"people","q":"Why has the tiny country of San Marino survived inside Italy for over 1,700 years?"},{"id":"scary-fun","t":"people","q":"Why do we enjoy being scared?"},{"id":"schengen-open-borders","t":"people","q":"Why can you cross between many European countries without ever showing a passport?"},{"id":"school","t":"people","q":"Why do we have to go to school?"},{"id":"school-bus-yellow","t":"people","q":"Why are school buses almost always that exact same bright yellow colour?"},{"id":"school-start-time-teens","t":"people","q":"Why do many teenagers struggle to concentrate in early-morning classes even after a full night's sleep?"},{"id":"school-subjects-separated","t":"people","q":"Why is the school day split into separate subject periods instead of one long, flowing lesson?"},{"id":"school-uniforms","t":"people","q":"Why do some schools require every student to wear the same uniform instead of their own clothes?"},{"id":"school-year-length","t":"people","q":"Why do school years around the world tend to be about the same length, even though the summer holidays that shape them don't come from farming at all?"},{"id":"scroll-to-codex","t":"people","q":"Why did books stop being rolled-up scrolls and become stacks of pages instead?"},{"id":"scrutineers-count-votes","t":"people","q":"Why are people from opposing parties allowed to stand and watch while your vote gets counted?"},{"id":"secret-ballot-invented","t":"people","q":"Why do people vote behind a curtain instead of just calling out their choice?"},{"id":"secrets","t":"people","q":"Why do we keep secrets?"},{"id":"self-defense-legal","t":"people","q":"Why isn't hurting someone automatically a crime if you did it to protect yourself?"},{"id":"serif-origin","t":"people","q":"Why do some letters have little feet at the ends of their strokes?"},{"id":"shorthand-speed","t":"people","q":"Why can shorthand writing keep up with someone talking at full speaking speed?"},{"id":"siblings-look-different","t":"people","q":"Why do siblings born to the same parents sometimes look completely different?"},{"id":"sign-different-countries","t":"people","q":"Why are British and American sign language completely different from each other?"},{"id":"sign-invented-by-kids","t":"people","q":"Why did a brand-new sign language get invented by children in a school?"},{"id":"sign-not-english","t":"people","q":"Why isn't sign language just English spelled out with your hands?"},{"id":"signature-different","t":"people","q":"Why is your signature never exactly the same twice, yet still counts as \"yours\"?"},{"id":"signing-with-x","t":"people","q":"Why did people who couldn't write sign important documents with an X?"},{"id":"silent-letters","t":"people","q":"Why do words like \"knife\" and \"night\" have letters nobody pronounces?"},{"id":"single-parent-families","t":"people","q":"Why do single-parent families work just as well as two-parent ones?"},{"id":"sky-lanterns","t":"people","q":"Why do some festivals release lit lanterns into the night sky?"},{"id":"slang-exists","t":"people","q":"Why do people invent slang words at all?"},{"id":"slang-teens","t":"people","q":"Why does slang go out of date almost as soon as adults start using it?"},{"id":"sleep-and-memory","t":"people","q":"Why does sleeping after you learn something help you remember it better the next day?"},{"id":"snowflake-six","t":"people","q":"Why does a snowflake almost always have six-fold symmetry?"},{"id":"sorry","t":"people","q":"Why do we say sorry?"},{"id":"sortition-athens","t":"people","q":"Why did ancient Athens pick many of its officials by lottery instead of voting for them?"},{"id":"sound-small-big","t":"people","q":"Why do words for tiny things often use an 'ee' sound?"},{"id":"south-africa-three-capitals","t":"people","q":"Why does South Africa have three different capital cities instead of just one?"},{"id":"south-sudan-newest","t":"people","q":"Why is South Sudan one of the world's newest countries?"},{"id":"soviet-breakup","t":"people","q":"Why did one country, the Soviet Union, suddenly become 15 separate countries?"},{"id":"spaced-repetition","t":"people","q":"Why does spreading study sessions out over several days beat cramming the night before?"},{"id":"spelling-weird","t":"people","q":"Why doesn't English spelling match how words actually sound?"},{"id":"spoiled-ballot","t":"people","q":"Why do some completed ballot papers not actually get counted at all?"},{"id":"stage-nerves","t":"people","q":"Why do I get nervous before speaking in front of people?"},{"id":"statute-of-limitations","t":"people","q":"Why can some crimes no longer be prosecuted once too many years have passed?"},{"id":"stepparents-real","t":"people","q":"Why can a stepparent become a real parent even without sharing your DNA?"},{"id":"stories","t":"people","q":"Why do people make up stories?"},{"id":"subvocalising","t":"people","q":"Why do beginner readers whisper or move their lips, even when reading silently?"},{"id":"sunflower-fibonacci","t":"people","q":"Why do sunflower seeds spiral out in numbers from the Fibonacci sequence?"},{"id":"surnames-around-world","t":"people","q":"Why do surnames get passed down differently in different countries?"},{"id":"swear-differs","t":"people","q":"Why are the rudest words completely different from country to country?"},{"id":"swear-pain","t":"people","q":"Why does swearing help you cope with pain?"},{"id":"swear-power","t":"people","q":"Why do swear words feel more powerful than ordinary words?"},{"id":"symbol-ballot-literacy","t":"people","q":"Why do some ballot papers show a picture or symbol next to each candidate's name?"},{"id":"tally-five","t":"people","q":"Why do tally marks come in bundles of five?"},{"id":"task-switching-cost","t":"people","q":"Why does trying to study and text back and forth at the same time make both take longer, even though it feels efficient?"},{"id":"tax-mandatory","t":"people","q":"Why is paying tax compulsory by law instead of something people can choose to do?"},{"id":"teams","t":"people","q":"Why do people love their team so much?"},{"id":"term-limits-president","t":"people","q":"Why are some leaders only allowed to hold office for a fixed number of terms, no matter how popular they are?"},{"id":"tessellate-three","t":"people","q":"Why can only triangles, squares and hexagons tile a floor by themselves with no gaps?"},{"id":"thanksgiving-myth","t":"people","q":"Why is the story of the 'first Thanksgiving' more complicated than the school version?"},{"id":"time-speeds-up","t":"people","q":"Why does time seem to go faster as you get older?"},{"id":"time-zones","t":"people","q":"Why do other countries have a different time?"},{"id":"times-tables-memorised","t":"people","q":"Why do kids still memorise times tables by heart when a calculator can do it instantly?"},{"id":"toast-raising-glass","t":"people","q":"Why do people raise a glass and say a toast at celebrations?"},{"id":"tongue-twisters-different","t":"people","q":"Why don't English tongue twisters trip up speakers of other languages?"},{"id":"tongue-twisters-trip","t":"people","q":"Why do tongue twisters trip up your tongue?"},{"id":"traits-skip-generation","t":"people","q":"Why do some traits like eye colour seem to skip a generation?"},{"id":"translation-jokes-hard","t":"people","q":"Why are jokes some of the hardest things to translate into another language?"},{"id":"trial-by-ordeal-myth","t":"people","q":"Why did medieval courts once decide guilt by making the accused hold a red-hot iron bar?"},{"id":"trick-or-treat","t":"people","q":"Why do children go door to door for Halloween?"},{"id":"twins-fingerprints","t":"people","q":"Why do identical twins end up with different fingerprints?"},{"id":"twins-language","t":"people","q":"Why do some twins seem to speak their own private language?"},{"id":"twins-run-families","t":"people","q":"Why do twins seem to run in some families?"},{"id":"two-houses-love","t":"people","q":"Why can you love two different houses after your parents live apart?"},{"id":"two-koreas","t":"people","q":"Why are North and South Korea two separate countries when they used to be one?"},{"id":"two-mums-two-dads","t":"people","q":"Why do some kids have two mums or two dads?"},{"id":"two-round-runoff","t":"people","q":"Why do some countries hold a whole second election just weeks after the first?"},{"id":"uk-four-nations","t":"people","q":"Why is the United Kingdom actually four countries bundled into one?"},{"id":"um-why","t":"people","q":"Why do we say 'um' and 'uh' so often when we talk?"},{"id":"unanimous-verdict","t":"people","q":"Why do some juries have to agree completely before they can convict someone?"},{"id":"union-jack-combo","t":"people","q":"Why is the Union Jack actually three flags squashed into one?"},{"id":"untranslatable","t":"people","q":"Why don't some words from other languages have one single English translation?"},{"id":"upper-house-appointed","t":"people","q":"Why does one half of some parliaments get elected while the other half doesn't?"},{"id":"upper-lower-case","t":"people","q":"Why does every letter come in a big version and a small version?"},{"id":"us-flag-stars-stripes","t":"people","q":"Why does the US flag have 50 stars but only 13 stripes?"},{"id":"vatican-smallest","t":"people","q":"Why is Vatican City its own country when it's smaller than most parks?"},{"id":"venice-doge-election","t":"people","q":"Why did the leader of old Venice get chosen through ten rounds of drawing lots and voting?"},{"id":"vietnam-latin","t":"people","q":"Why does Vietnamese use the same letters as English instead of Chinese characters?"},{"id":"village-council-consensus","t":"people","q":"Why do some communities choose a leader by talking until everyone agrees, instead of counting votes?"},{"id":"visa-need","t":"people","q":"Why do some countries let you in with no paperwork while others demand a visa first?"},{"id":"voice-cracks-puberty","t":"people","q":"Why does your voice crack and change during puberty?"},{"id":"voting","t":"people","q":"Why do people vote?"},{"id":"voting-age-lowered","t":"people","q":"Why do a few countries let you vote at 16, when most say you must wait until 18?"},{"id":"voting-booth-curtain","t":"people","q":"Why does a voting booth need a curtain when nobody's watching what you buy at a shop?"},{"id":"we-argue","t":"people","q":"Why do people argue?"},{"id":"wedding-ring-finger","t":"people","q":"Why is a wedding ring worn on this particular finger?"},{"id":"wedding-white-dress","t":"people","q":"Why do many Western brides wear a white dress?"},{"id":"western-sahara","t":"people","q":"Why is Western Sahara one of the few places on Earth without a settled owner?"},{"id":"what-is-a-strike","t":"people","q":"Why do workers sometimes refuse to work all at once?"},{"id":"whistleblower-protection","t":"people","q":"Why do some laws specifically protect people who report wrongdoing at their own workplace?"},{"id":"whistled-language","t":"people","q":"Why can people on La Gomera whistle whole sentences to each other?"},{"id":"why-actors-get-royalties","t":"people","q":"Why do actors sometimes get paid again every time an old show reruns on television?"},{"id":"why-advertising-jingles-stick","t":"people","q":"Why do ad jingles get stuck in your head?"},{"id":"why-age-limits-for-jobs","t":"people","q":"Why can't kids get a regular paid job before a certain age?"},{"id":"why-anger-feels-hot","t":"people","q":"Why does anger feel hot?"},{"id":"why-anger-gender-norms","t":"people","q":"Why are boys and girls often taught different rules about showing anger?"},{"id":"why-anger-takes-time-cool","t":"people","q":"Why can't you just switch off anger the moment you decide to?"},{"id":"why-anger-venting-myth","t":"people","q":"Why doesn't punching a pillow actually get rid of your anger?"},{"id":"why-apprentices-earn-less","t":"people","q":"Why do apprentices get paid less while they're learning a trade?"},{"id":"why-atm-check-notes","t":"people","q":"Why can a machine tell a fake note from a real one in an instant?"},{"id":"why-auctions-bidding","t":"people","q":"Why does an auction let a crowd decide the price instead of the seller?"},{"id":"why-avoid-talking-feelings","t":"people","q":"Why do some families almost never talk about feelings out loud?"},{"id":"why-awe-feels-big","t":"people","q":"Why do enormous things make you feel small in a good way?"},{"id":"why-bakers-work-before-dawn","t":"people","q":"Why do bakers start work in the middle of the night?"},{"id":"why-bank-id-check","t":"people","q":"Why does a bank ask so many questions before opening an account?"},{"id":"why-banks-lend-your-money","t":"people","q":"Why doesn't a bank just keep your money sitting in a vault?"},{"id":"why-barcodes-prices","t":"people","q":"Why does a shop scanner know a price just from stripes on a box?"},{"id":"why-basic-emotions-debate","t":"people","q":"Why isn't there an agreed number of 'basic' emotions?"},{"id":"why-borrowing-interest","t":"people","q":"Why do you have to pay back more than you borrowed?"},{"id":"why-bow-instead-shake","t":"people","q":"Why do some countries bow instead of shaking hands?"},{"id":"why-burp-approved-some-cultures","t":"people","q":"Why is burping after a meal rude in some places and a compliment in others?"},{"id":"why-cards-work","t":"people","q":"Why does tapping a card pay for something with no cash at all?"},{"id":"why-ceo-exists","t":"people","q":"Why does a big company need one person in charge of everyone?"},{"id":"why-cheques-take-days","t":"people","q":"Why does a cheque take days to clear but a card payment is instant?"},{"id":"why-child-factory-work-ended","t":"people","q":"Why did children stop working in factories?"},{"id":"why-chopsticks-rules","t":"people","q":"Why is it bad manners to stick chopsticks upright in a rice bowl?"},{"id":"why-coin-metal-value","t":"people","q":"Why isn't the metal in a coin worth the amount stamped on it?"},{"id":"why-commute-to-work","t":"people","q":"Why do so many people travel away from home just to work?"},{"id":"why-company-departments","t":"people","q":"Why does a company split into different departments?"},{"id":"why-compliments-awkward","t":"people","q":"Why does getting a compliment sometimes feel awkward?"},{"id":"why-counterfeit-hard","t":"people","q":"Why is it so hard to make a fake banknote that passes as real?"},{"id":"why-cover-mouth-cough","t":"people","q":"Why is it polite to cover your mouth when you cough?"},{"id":"why-cover-yawn","t":"people","q":"Why is it polite to cover your mouth when you yawn?"},{"id":"why-cowrie-shells-money","t":"people","q":"Why did tiny sea shells work as money in some ancient trade?"},{"id":"why-credit-card-debt","t":"people","q":"Why does paying with a credit card mean paying more if you're late?"},{"id":"why-crowd-emotion-spread","t":"people","q":"Why can panic spread through a crowd faster than any one person could explain it?"},{"id":"why-crying-signals-for-help","t":"people","q":"Why does crying make other people want to help you?"},{"id":"why-currency-symbols","t":"people","q":"Why does money have symbols like $ or £ instead of just words?"},{"id":"why-diamonds-expensive","t":"people","q":"Why are diamonds so expensive when they aren't actually that rare?"},{"id":"why-different-clothing-etiquette-religious","t":"people","q":"Why are visitors asked to cover shoulders before entering some religious buildings?"},{"id":"why-different-currencies","t":"people","q":"Why doesn't every country use the same money?"},{"id":"why-different-cutlery-order","t":"people","q":"Why do fancy table settings put out so much cutlery at once?"},{"id":"why-different-eating-hands","t":"people","q":"Why is eating with your left hand rude in some countries but fine in others?"},{"id":"why-different-eye-contact-rules","t":"people","q":"Why is eye contact respectful in some cultures and rude in others?"},{"id":"why-different-funeral-manners","t":"people","q":"Why do different cultures wear such different colours to funerals?"},{"id":"why-different-greeting-kiss-count","t":"people","q":"Why do some countries greet with one cheek kiss, others with two or three?"},{"id":"why-different-personal-space-cultures","t":"people","q":"Why do people from some countries stand closer together while talking?"},{"id":"why-different-shop-prices","t":"people","q":"Why can the same toy cost different amounts in two different shops?"},{"id":"why-different-table-manners-noise","t":"people","q":"Why is slurping noodles rude at some tables and fine at others?"},{"id":"why-different-tipping-rules","t":"people","q":"Why is a tip generous in one country and slightly insulting in another?"},{"id":"why-digital-money-not-real-cash","t":"people","q":"Why is the number in a banking app not money sitting somewhere?"},{"id":"why-disgust-moral","t":"people","q":"Why can breaking a rule feel disgusting, not just wrong?"},{"id":"why-display-rules-differ","t":"people","q":"Why do people in different cultures show feelings so differently?"},{"id":"why-economies-of-scale","t":"people","q":"Why do things get cheaper once factories make millions of them?"},{"id":"why-eight-hour-day","t":"people","q":"Why is a standard workday about eight hours long?"},{"id":"why-elbows-off-table","t":"people","q":"Why were children once told never to put their elbows on the table?"},{"id":"why-emotion-body-locations","t":"people","q":"Why do people everywhere point to the same parts of the body for the same feeling?"},{"id":"why-emotion-regulation-skill","t":"people","q":"Why can calming yourself down be practised like a skill?"},{"id":"why-emotion-words-vary","t":"people","q":"Why do some languages have a word for a feeling that English doesn't?"},{"id":"why-emotional-labor-tiring","t":"people","q":"Why is smiling all day at a job so tiring?"},{"id":"why-emotions-contagious","t":"people","q":"Why can one person's mood spread through a whole room?"},{"id":"why-emotions-exist","t":"people","q":"Why do we have emotions at all?"},{"id":"why-emotions-fade","t":"people","q":"Why doesn't even the best day keep you happy forever?"},{"id":"why-emotions-peak-fade-quickly","t":"people","q":"Why do we expect a big feeling to last longer than it actually does?"},{"id":"why-empathy-feel-others","t":"people","q":"Why can seeing someone else hurt make you wince too?"},{"id":"why-exchange-rates-change","t":"people","q":"Why does the exchange rate change from day to day?"},{"id":"why-factory-vs-craft-work","t":"people","q":"Why is making something in a factory so different from a craftsperson making it by hand?"},{"id":"why-fake-smile-different","t":"people","q":"Why can you often tell a fake smile from a real one?"},{"id":"why-family-business-passed-down","t":"people","q":"Why do some businesses get passed down through the same family for generations?"},{"id":"why-farmers-follow-seasons","t":"people","q":"Why does a farmer's work change completely through the year?"},{"id":"why-farmers-market-cheaper","t":"people","q":"Why can food cost less at a farmers market than a supermarket?"},{"id":"why-fear-vs-anxiety","t":"people","q":"Why is fear different from worry, even though they feel similar?"},{"id":"why-first-coins-lydia","t":"people","q":"Why do historians think one small ancient kingdom invented the coin?"},{"id":"why-fruit-out-of-season","t":"people","q":"Why is fruit dearer when it's out of season?"},{"id":"why-get-promoted","t":"people","q":"Why do people get promoted at work?"},{"id":"why-gift-giving-reciprocal","t":"people","q":"Why do people feel they need to give something back after a gift?"},{"id":"why-gold-standard-ended","t":"people","q":"Why doesn't paper money get swapped for gold any more?"},{"id":"why-gold-was-money","t":"people","q":"Why did people choose gold to be money?"},{"id":"why-good-cry-feels-better","t":"people","q":"Why do people say they feel better after 'a good cry'?"},{"id":"why-guilt-vs-shame","t":"people","q":"Why are guilt and shame actually two different feelings?"},{"id":"why-haggling-markets","t":"people","q":"Why do people haggle over prices in some markets but not in supermarkets?"},{"id":"why-happy-tears","t":"people","q":"Why do people sometimes cry when they're happy?"},{"id":"why-hide-crying-public","t":"people","q":"Why do people often hold back tears in public but not at home?"},{"id":"why-hide-true-feelings","t":"people","q":"Why do we sometimes hide what we're really feeling?"},{"id":"why-hospitals-shift-work","t":"people","q":"Why do hospitals have workers on duty all through the night?"},{"id":"why-hosts-serve-guests-first","t":"people","q":"Why are hosts expected to serve guests before serving themselves?"},{"id":"why-hourly-vs-salary","t":"people","q":"Why do some jobs pay by the hour and others pay the same no matter how long you work?"},{"id":"why-illegal-to-print-money","t":"people","q":"Why can't you just print your own money?"},{"id":"why-inflation","t":"people","q":"Why does the same bag of lollies cost more than it used to?"},{"id":"why-interest-rates-change","t":"people","q":"Why do banks change their interest rates?"},{"id":"why-jealousy-function","t":"people","q":"Why do we feel jealous?"},{"id":"why-jobs-disappear-over-time","t":"people","q":"Why do some jobs completely disappear after a while?"},{"id":"why-jobs-seasonal","t":"people","q":"Why do some jobs only exist for part of the year?"},{"id":"why-licence-for-jobs","t":"people","q":"Why do some jobs need an official licence before you can do them?"},{"id":"why-loan-costs-more-over-time","t":"people","q":"Why does a loan end up costing more the longer it takes to repay?"},{"id":"why-lonely-in-a-crowd","t":"people","q":"Why can you feel lonely even when you're surrounded by people?"},{"id":"why-long-training-jobs","t":"people","q":"Why do some jobs take ten years or more to train for?"},{"id":"why-machines-take-jobs","t":"people","q":"Why do machines take over jobs that people used to do?"},{"id":"why-manners-change-over-time","t":"people","q":"Why do manners once seen as essential sometimes vanish within a couple of generations?"},{"id":"why-manners-child-learn-copy","t":"people","q":"Why do children learn manners mostly by copying adults, not by being told rules?"},{"id":"why-manners-differ-digital-messages","t":"people","q":"Why do people worry a text message sounds rude, in a way old letters rarely did?"},{"id":"why-manners-signal-cooperation","t":"people","q":"Why do sociologists think politeness exists, if it doesn't change what people want?"},{"id":"why-milled-edges","t":"people","q":"Why do coins have ridged edges?"},{"id":"why-minimum-wage","t":"people","q":"Why is there a lowest amount employers are allowed to pay?"},{"id":"why-mixed-feelings","t":"people","q":"Why can you feel two different emotions at the same time?"},{"id":"why-name-feelings-helps","t":"people","q":"Why can just naming a feeling out loud make it easier to handle?"},{"id":"why-napkin-on-lap","t":"people","q":"Why do formal meals expect a napkin on your lap, not the table?"},{"id":"why-nervous-laugh","t":"people","q":"Why do people sometimes laugh at bad news?"},{"id":"why-new-jobs-appear","t":"people","q":"Why do brand new kinds of jobs keep appearing that never existed before?"},{"id":"why-nostalgia-bittersweet","t":"people","q":"Why does remembering old times feel both happy and sad?"},{"id":"why-not-arrive-empty-handed","t":"people","q":"Why is it impolite to visit someone's home for dinner empty-handed?"},{"id":"why-not-barter","t":"people","q":"Why didn't people barter before money was invented?"},{"id":"why-not-everyone-can-be-anything","t":"people","q":"Why can't everyone become an astronaut or a professional athlete just by trying hard enough?"},{"id":"why-not-loud-phone-public","t":"people","q":"Why is talking loudly on the phone in a quiet place rude?"},{"id":"why-not-one-manners","t":"people","q":"Why isn't there one correct set of manners for the whole world?"},{"id":"why-not-pick-teeth-fingers","t":"people","q":"Why is picking food from your teeth with a finger less polite than a toothpick?"},{"id":"why-not-point-with-finger","t":"people","q":"Why is pointing with your finger rude in some cultures?"},{"id":"why-not-slam-door","t":"people","q":"Why is slamming a door rude even if nobody says anything?"},{"id":"why-not-talk-mouth-full","t":"people","q":"Why is talking with your mouth full considered rude almost everywhere?"},{"id":"why-note-portraits","t":"people","q":"Why do banknotes have a person's face on them?"},{"id":"why-notes-not-paper","t":"people","q":"Why aren't banknotes actually made of paper?"},{"id":"why-outgrow-tantrums","t":"people","q":"Why do toddlers have tantrums that older kids mostly grow out of?"},{"id":"why-overtime-pay","t":"people","q":"Why do some workers get paid extra for working past their normal hours?"},{"id":"why-paid-annual-leave","t":"people","q":"Why do full-time workers get a number of paid days off every year?"},{"id":"why-pay-varies-city-town","t":"people","q":"Why does the same job pay more in a big city than a small town?"},{"id":"why-people-fired","t":"people","q":"Why do people sometimes lose their job?"},{"id":"why-petrol-price-changes","t":"people","q":"Why does the price of petrol seem to change almost every day?"},{"id":"why-plumber-charges-for-quick-fix","t":"people","q":"Why does a tradesperson sometimes charge a lot for a job that only takes them ten minutes?"},{"id":"why-polymer-notes-durable","t":"people","q":"Why do plastic banknotes survive a trip through the washing machine?"},{"id":"why-price-999","t":"people","q":"Why do so many prices end in .99 instead of a round number?"},{"id":"why-pride-display-universal","t":"people","q":"Why do winners around the world strike the exact same pose?"},{"id":"why-prisons","t":"people","q":"Why do modern legal systems lock people up instead of only fining or physically punishing them?"},{"id":"why-professionals-keep-training","t":"people","q":"Why do some workers have to keep learning even after they've qualified?"},{"id":"why-public-holiday-pay","t":"people","q":"Why do some jobs pay extra for working on a public holiday?"},{"id":"why-queue-politely","t":"people","q":"Why do people wait their turn in a queue instead of pushing in?"},{"id":"why-redundancy-pay","t":"people","q":"Why do workers sometimes get extra money when a company lays them off?"},{"id":"why-relief-feels-emotional","t":"people","q":"Why does relief sometimes make you cry or laugh?"},{"id":"why-retire","t":"people","q":"Why do people stop working when they get old?"},{"id":"why-retirement-age-law","t":"people","q":"Why do some jobs set an exact age when you must stop working?"},{"id":"why-rsvp-important","t":"people","q":"Why is it rude to not reply to an invitation at all?"},{"id":"why-sad-songs-good","t":"people","q":"Why can a sad song make you feel good?"},{"id":"why-savings-interest","t":"people","q":"Why does a bank pay you for leaving your money there?"},{"id":"why-say-bless-you","t":"people","q":"Why do people say \"bless you\" when someone sneezes?"},{"id":"why-say-excuse-me","t":"people","q":"Why do people say \"excuse me\" before interrupting someone?"},{"id":"why-say-goodbye-differently","t":"people","q":"Why does leaving a gathering take much longer in some cultures than others?"},{"id":"why-say-hello-first","t":"people","q":"Why is it rude to walk past someone you know without saying hello?"},{"id":"why-say-hello-phone","t":"people","q":"Why do we say \"hello\" when answering the phone, when it's not really greeting anyone in the room?"},{"id":"why-say-im-fine","t":"people","q":"Why do we say 'I'm fine' when we're not?"},{"id":"why-say-may-i","t":"people","q":"Why does \"may I\" sound more polite than \"can I\"?"},{"id":"why-say-no-thank-you","t":"people","q":"Why do people say \"no, thank you\" instead of just \"no\"?"},{"id":"why-say-please","t":"people","q":"Why does adding \"please\" make a request sound less bossy?"},{"id":"why-say-sorry-not-fault","t":"people","q":"Why do people sometimes say sorry when it clearly wasn't their fault?"},{"id":"why-schadenfreude","t":"people","q":"Why can it feel satisfying when someone unpleasant gets in trouble?"},{"id":"why-secondhand-embarrassment","t":"people","q":"Why can watching someone else embarrass themselves make you cringe?"},{"id":"why-serial-numbers","t":"people","q":"Why does every banknote have its own number printed on it?"},{"id":"why-shift-work-rotates","t":"people","q":"Why do shift workers often change which shift they're on?"},{"id":"why-shoes-off-indoors","t":"people","q":"Why do some homes ask you to take your shoes off at the door?"},{"id":"why-shops-play-music","t":"people","q":"Why do shops play music while you're shopping?"},{"id":"why-shops-sales","t":"people","q":"Why do shops slash their prices for a 'sale'?"},{"id":"why-sick-leave","t":"people","q":"Why do some jobs still pay you when you're too sick to work?"},{"id":"why-silence-can-be-rude","t":"people","q":"Why can staying silent feel ruder than saying the wrong thing?"},{"id":"why-specialise-not-farm","t":"people","q":"Why doesn't everyone just grow their own food instead of having a job?"},{"id":"why-stock-market-up-down","t":"people","q":"Why does the stock market go up and down?"},{"id":"why-supermarket-milk-back","t":"people","q":"Why is milk almost always at the very back of the supermarket?"},{"id":"why-tax","t":"people","q":"Why do we have to pay tax?"},{"id":"why-teachers-summer-break","t":"people","q":"Why do teachers get such a long break over summer?"},{"id":"why-teens-feel-more","t":"people","q":"Why do feelings seem so much bigger during the teenage years?"},{"id":"why-thank-you-note","t":"people","q":"Why do some families write thank-you notes after a gift?"},{"id":"why-time-heals-grief","t":"people","q":"Why does sadness over a big loss slowly get easier to carry?"},{"id":"why-tips-at-some-jobs","t":"people","q":"Why do some jobs let workers keep money customers give them directly?"},{"id":"why-titles-mr-mrs-formal","t":"people","q":"Why do some adults expect children to call them Mr or Mrs?"},{"id":"why-toast-clink-glasses","t":"people","q":"Why do people clink glasses together when making a toast?"},{"id":"why-toy-fad-price-surge","t":"people","q":"Why can a hot new toy suddenly cost triple its normal price?"},{"id":"why-unions-exist","t":"people","q":"Why do workers join together into unions?"},{"id":"why-venting-to-friend-helps","t":"people","q":"Why does talking to a friend about anger help more than punching something?"},{"id":"why-volunteer-unpaid","t":"people","q":"Why do some people work hard at a job that pays nothing at all?"},{"id":"why-weekends","t":"people","q":"Why do most people get weekends off work?"},{"id":"why-work-uniforms","t":"people","q":"Why do people wear uniforms at some jobs?"},{"id":"why-workplace-safety-rules","t":"people","q":"Why do workplaces have so many safety rules, like hard hats and warning signs?"},{"id":"wishbone-pull","t":"people","q":"Why do families pull apart a wishbone at a feast?"},{"id":"womens-suffrage-first","t":"people","q":"Why was New Zealand first to let women vote in national elections?"},{"id":"word-meaning-shift","t":"people","q":"Why did the word 'nice' used to be an insult?"},{"id":"write-boustrophedon","t":"people","q":"Why did ancient Greek writing zigzag left, then right, then left again?"},{"id":"yugoslavia-breakup","t":"people","q":"Why did the country of Yugoslavia split into so many small countries?"},{"id":"zero-divide","t":"people","q":"Why can't you divide a number by zero?"},{"id":"zero-invented-twice","t":"people","q":"Why was zero worked out in more than one place, with nobody copying anybody?"},{"id":"zero-no-romans","t":"people","q":"Why didn't the Romans have a symbol for zero?"},{"id":"zero-reached-europe-late","t":"people","q":"Why did zero take centuries to reach Europe after India had already mastered it?"},{"id":"acc-isolation","t":"ocean","q":"Why does a ring of fast water around Antarctica help keep the whole continent locked in the cold?"},{"id":"algal-bloom-not-always-toxic","t":"ocean","q":"Why doesn't a red or brown bloom in the sea always mean the water is dangerous?"},{"id":"amazon-plume-reaches-far","t":"ocean","q":"Why can a river's brown plume still be visible hundreds of kilometres out at sea?"},{"id":"amoc-slowdown","t":"ocean","q":"Why are scientists keeping such a close watch on the Atlantic's deepest current?"},{"id":"anchor-chain-corrode-sea","t":"ocean","q":"Why do ship anchors and chains rust and corrode faster in the sea than in a river?"},{"id":"anemone-jelly-shared-weapon","t":"ocean","q":"Why do jellyfish and sea anemones share the exact same stinging weapon?"},{"id":"anglerfish-female-giant","t":"ocean","q":"Why are female anglerfish sometimes far bigger than males of exactly the same species?"},{"id":"anglerfish-fused-mate","t":"ocean","q":"Why do some male anglerfish fuse permanently onto a female's body?"},{"id":"anglerfish-lure-glow","t":"ocean","q":"Why does an anglerfish dangle a glowing lure right in front of its own mouth?"},{"id":"antarctic-circumpolar","t":"ocean","q":"Why does one current carry more water than every river on Earth put together?"},{"id":"argo-floats","t":"ocean","q":"Why do thousands of robot floats sink and resurface across the ocean, all on their own?"},{"id":"artificial-reef-shipwreck","t":"ocean","q":"Why do sunken shipwrecks sometimes end up covered in thriving coral reef?"},{"id":"bacteria-light-pouch-symbiosis","t":"ocean","q":"Why do some deep sea fish keep living, glowing bacteria in a special pouch under their eyes?"},{"id":"baltic-sea-low-salt","t":"ocean","q":"Why is the Baltic Sea so much less salty than the sea around it?"},{"id":"barnacles-whales","t":"ocean","q":"Why do barnacles ride on whales?"},{"id":"barreleye-transparent-head","t":"ocean","q":"Why does the barreleye fish have a see-through head?"},{"id":"barrier-reef","t":"ocean","q":"Why is the Great Barrier Reef so big?"},{"id":"beach-season-change","t":"ocean","q":"Why do some beaches lose their sand in winter storms and get it back again in summer?"},{"id":"beached-jelly-no-tentacles","t":"ocean","q":"Why can a jellyfish washed up on sand look like it has no tentacles left?"},{"id":"betta-labyrinth","t":"ocean","q":"Why can betta fish live in a small bowl with little oxygen?"},{"id":"biofluorescent-reef-glow","t":"ocean","q":"Why can some coral and reef fish glow bright green or red under a special blue light?"},{"id":"bioluminescent-waves-glow","t":"ocean","q":"Why can breaking waves glow blue in the dark on some nights?"},{"id":"black-sand-dark-water","t":"ocean","q":"Why can shallow water over black volcanic sand look almost as dark as deep water?"},{"id":"black-sea-name-origin","t":"ocean","q":"Why is the Black Sea called black when its surface looks much like any other sea?"},{"id":"black-smoker-chimney","t":"ocean","q":"Why do some hydrothermal vents look like smoking black chimneys?"},{"id":"blanket-octopus-stolen-tentacles","t":"ocean","q":"Why does one octopus rip off jellyfish tentacles to carry as weapons?"},{"id":"blue-ringed-octopus-bite-unnoticed","t":"ocean","q":"Why can a blue-ringed octopus bite someone without them feeling it?"},{"id":"blue-ringed-octopus-rings-warning","t":"ocean","q":"Why do a blue-ringed octopus's rings only appear when it's angry?"},{"id":"box-jellyfish-danger","t":"ocean","q":"Why is the box jellyfish one of the most dangerous stingers in the sea?"},{"id":"box-jellyfish-eyes","t":"ocean","q":"Why does the box jellyfish have eyes when most jellyfish don't?"},{"id":"boxer-crab-anemone-gloves","t":"ocean","q":"Why does a boxer crab carry a stinging anemone in each claw?"},{"id":"boxfish-shape","t":"ocean","q":"Why is a boxfish shaped like a cube?"},{"id":"brain-coral-maze-pattern","t":"ocean","q":"Why does brain coral grow in a winding, maze-like pattern instead of branches?"},{"id":"brine-rejection","t":"ocean","q":"Why does freezing sea ice leave the water underneath saltier than before?"},{"id":"brine-shrimp-salty-lake","t":"ocean","q":"Why can brine shrimp thrive in water too salty for almost any fish?"},{"id":"calm-sea-mirror","t":"ocean","q":"Why can a dead calm sea turn into an almost perfect mirror?"},{"id":"catfish-whiskers","t":"ocean","q":"Why do catfish have whiskers around their mouths?"},{"id":"choppy-sea-duller-blue","t":"ocean","q":"Why does choppy, wind-ruffled water look paler than glassy water?"},{"id":"christmas-tree-worm-coral-home","t":"ocean","q":"Why do tiny spiral-shaped Christmas tree worms vanish instantly the moment a shadow passes over them?"},{"id":"cichlid-throat-teeth","t":"ocean","q":"Why do some fish have a second set of teeth in their throat?"},{"id":"cleaner-wrasse-station","t":"ocean","q":"Why do big reef fish line up and wait patiently at tiny cleaning stations?"},{"id":"clear-water-biological-desert","t":"ocean","q":"Why is the clearest, bluest ocean water often the emptiest of life?"},{"id":"clownfish-anemone","t":"ocean","q":"Why don't clownfish get stung by their anemone?"},{"id":"coastal-fog-current","t":"ocean","q":"Why do cold currents wrap some coastlines in fog almost every summer morning?"},{"id":"coccolithophore-milky-bloom","t":"ocean","q":"Why can algae too small to see turn a huge patch of ocean milky turquoise?"},{"id":"cold-seep-methane-life","t":"ocean","q":"Why can some patches of the deep seafloor leak methane and still support thriving life?"},{"id":"colossal-squid-swivel-hooks","t":"ocean","q":"Why does the colossal squid have swivelling hooks on its tentacles instead of just suckers?"},{"id":"comb-jelly-no-sting","t":"ocean","q":"Why do comb jellies look like jellyfish but never sting?"},{"id":"cone-snail-harpoon","t":"ocean","q":"Why does a cone snail fire a harpoon instead of biting its prey?"},{"id":"cone-snail-kills-fast","t":"ocean","q":"Why can a cone snail's sting drop a fish faster than almost any other hunter?"},{"id":"coral","t":"ocean","q":"Why is coral colourful, and why does it go white?"},{"id":"coral-age-growth-bands","t":"ocean","q":"Why can scientists read a slice of coral skeleton almost like the rings of a tree?"},{"id":"coral-algae-farming","t":"ocean","q":"Why does coral keep tiny algae living inside its own body?"},{"id":"coral-bleach-recovery","t":"ocean","q":"Why can some bleached coral turn back to its normal colour again?"},{"id":"coral-disease-band","t":"ocean","q":"Why can a dark line slowly creep across a coral colony and kill everything behind it?"},{"id":"coral-feeds-at-night","t":"ocean","q":"Why do coral polyps stretch out their tentacles mostly at night?"},{"id":"coral-larvae-settle","t":"ocean","q":"Why does a floating coral larva need to find exactly the right patch of seafloor before it can settle?"},{"id":"coral-mass-spawning","t":"ocean","q":"Why do whole reefs of coral release their eggs on the very same night?"},{"id":"coral-nematocyst-sting","t":"ocean","q":"Why can coral sting you even though it looks harmless?"},{"id":"coral-polyp-animal","t":"ocean","q":"Why is coral an animal and not a plant or a rock?"},{"id":"coral-reef-not-single-species-city","t":"ocean","q":"Why is calling a whole reef just 'the coral' actually a mistake?"},{"id":"coral-reef-nursery-fish","t":"ocean","q":"Why do so many young fish species grow up on a reef before moving elsewhere as adults?"},{"id":"coral-related-jellyfish","t":"ocean","q":"Why are coral polyps close relatives of jellyfish?"},{"id":"coral-restoration-fragment","t":"ocean","q":"Why can breaking a piece of coral off sometimes help a reef instead of harming it?"},{"id":"coral-sweeper-tentacle-fight","t":"ocean","q":"Why do neighbouring coral colonies sometimes fight each other for space?"},{"id":"coral-symbiosis-only-clear-water","t":"ocean","q":"Why do most reef-building coral struggle to survive in cloudy or muddy water?"},{"id":"coriolis-currents","t":"ocean","q":"Why does the spinning Earth steer a giant ocean current but not the water in your bathtub?"},{"id":"counterillumination-belly-glow","t":"ocean","q":"Why do some deep sea animals glow on their undersides just to disappear?"},{"id":"crabs-sideways","t":"ocean","q":"Why do crabs walk sideways?"},{"id":"crown-of-thorns-outbreak","t":"ocean","q":"Why can a single kind of starfish devastate an entire reef?"},{"id":"crystal-jelly-glowing-gene","t":"ocean","q":"Why did one glowing jellyfish change how scientists study every living cell?"},{"id":"current-drift-navigation","t":"ocean","q":"Why did old sailors work out where a current was by how wrong their own maths turned out to be?"},{"id":"current-invisible","t":"ocean","q":"Why can a current sweep a swimmer off course without the water ever looking like it's moving?"},{"id":"current-rings-eddies","t":"ocean","q":"Why does a current pinch off a spinning ring of water and set it drifting on its own?"},{"id":"currents-move-heat","t":"ocean","q":"Why does the Gulf Stream move more heat every second than every power station on Earth combined?"},{"id":"cut-stings-seawater","t":"ocean","q":"Why does a scrape or cut sting extra sharply in the ocean?"},{"id":"cuttlefish-cuttlebone-buoyancy","t":"ocean","q":"Why does a cuttlefish carry a chalky, gas-filled bone inside its body?"},{"id":"cuttlefish-embryo-watches-through-egg","t":"ocean","q":"Why can a cuttlefish still developing inside its own egg already be learning what to hunt?"},{"id":"cuttlefish-flamboyant-walker","t":"ocean","q":"Why does the flamboyant cuttlefish walk across the seafloor instead of swimming like other cuttlefish?"},{"id":"cuttlefish-hatch-fully-capable","t":"ocean","q":"Why can a baby cuttlefish camouflage and hunt perfectly on its own within hours of hatching?"},{"id":"cuttlefish-hypnotic-cloud-display","t":"ocean","q":"Why does a cuttlefish flash a moving band of stripes across its skin right before it strikes at a crab?"},{"id":"cuttlefish-male-disguise-sneak","t":"ocean","q":"Why does a male cuttlefish sometimes display female colours on half of his own body?"},{"id":"cuttlefish-mass-mating-gathering","t":"ocean","q":"Why do thousands of giant cuttlefish gather in one place every year, only to die soon after?"},{"id":"cuttlefish-not-actually-fish","t":"ocean","q":"Why is a cuttlefish not actually a fish at all, despite its name?"},{"id":"cuttlefish-tentacle-pouches","t":"ocean","q":"Why do a cuttlefish's two longest arms seem to disappear when it isn't hunting?"},{"id":"cuttlefish-three-skin-layers","t":"ocean","q":"Why does cuttlefish skin need three completely different kinds of colour cells stacked on top of each other?"},{"id":"cuttlefish-w-shaped-pupil","t":"ocean","q":"Why does a cuttlefish's eye have a strange W-shaped pupil instead of a round one?"},{"id":"damselfish-algae-farm","t":"ocean","q":"Why do some small damselfish attack fish many times their own size on a reef?"},{"id":"dead-sea-lifeless","t":"ocean","q":"Why is the Dead Sea almost completely lifeless?"},{"id":"deep-clear-water-near-black","t":"ocean","q":"Why can very deep, clear ocean water look almost black rather than blue?"},{"id":"deep-cold","t":"ocean","q":"Why is the sea cold at the bottom even in the tropics?"},{"id":"deep-dark","t":"ocean","q":"Why is the deep sea dark?"},{"id":"deep-fish-eye-extremes","t":"ocean","q":"Why do some deep sea fish have enormous eyes while others have almost none?"},{"id":"deep-fish-gelatinous-body","t":"ocean","q":"Why are so many deep sea fish soft and jelly-like instead of muscular?"},{"id":"deep-fish-no-swim-bladder","t":"ocean","q":"Why do many deep sea fish have no swim bladder at all?"},{"id":"deep-glow","t":"ocean","q":"Why do deep sea animals glow?"},{"id":"deep-pressure","t":"ocean","q":"Why would the deep sea squash you?"},{"id":"deep-sea-coral-no-light","t":"ocean","q":"Why can coral grow in the freezing dark of the deep sea without any sunlight?"},{"id":"deep-sea-food-scarcity","t":"ocean","q":"Why do many deep sea animals go months between meals without starving?"},{"id":"deep-sea-gigantism","t":"ocean","q":"Why do some deep sea creatures grow far bigger than their shallow-water relatives?"},{"id":"deep-sea-mining-nodules","t":"ocean","q":"Why are companies interested in mining potato-sized rocks scattered across the deep ocean floor?"},{"id":"deep-sea-siphonophore-length","t":"ocean","q":"Why can a single deep sea animal be longer than a blue whale?"},{"id":"desalination-brine-leftover","t":"ocean","q":"Why does turning seawater into drinking water leave behind a super-salty leftover that's tricky to get rid of?"},{"id":"desalination-energy-hungry","t":"ocean","q":"Why does turning seawater into drinking water take so much energy?"},{"id":"dolphin-aggression-myth","t":"ocean","q":"Why aren't dolphins the endlessly gentle, always-friendly animals people imagine?"},{"id":"dolphin-air-breathing-conscious","t":"ocean","q":"Why must a dolphin remember to breathe, unlike a human who does it without thinking?"},{"id":"dolphin-baby-position-echelon","t":"ocean","q":"Why does a baby dolphin swim glued to its mother's side for the first weeks?"},{"id":"dolphin-bow-ride","t":"ocean","q":"Why do dolphins rush over to ride the bow wave of a boat?"},{"id":"dolphin-brain-size-comparison","t":"ocean","q":"Why does a dolphin's brain compare closely with a human's in relative size?"},{"id":"dolphin-breach-tail-slap-alarm","t":"ocean","q":"Why does a dolphin sometimes slap its tail flat against the water with a loud crack?"},{"id":"dolphin-bubble-ring-play","t":"ocean","q":"Why do dolphins blow spinning rings of bubbles just to play with them?"},{"id":"dolphin-calf-play-learning","t":"ocean","q":"Why do young dolphins spend so much of their time just playing?"},{"id":"dolphin-common-vs-bottlenose-size","t":"ocean","q":"Why does \"dolphin\" cover animals from the size of a large dog to bigger than a bus?"},{"id":"dolphin-cooperative-fishing-humans","t":"ocean","q":"Why do wild dolphins in one Brazilian town help fishers catch fish?"},{"id":"dolphin-dorsal-fin-id","t":"ocean","q":"Why can scientists identify individual dolphins just from their dorsal fin?"},{"id":"dolphin-echolocation-clicks","t":"ocean","q":"Why do dolphins click their jaws to find fish in murky water?"},{"id":"dolphin-echolocation-vs-eyesight","t":"ocean","q":"Why do dolphins keep clicking to hunt even in perfectly clear, sunlit water?"},{"id":"dolphin-fish-stun-click","t":"ocean","q":"Why can a dolphin's click be loud enough to stun a fish?"},{"id":"dolphin-fish-whack-tail","t":"ocean","q":"Why does a dolphin sometimes launch a fish high into the air with its tail?"},{"id":"dolphin-fission-fusion-society","t":"ocean","q":"Why do a dolphin's swimming companions change from one day to the next?"},{"id":"dolphin-jaw-hearing","t":"ocean","q":"Why does a dolphin listen for echoes through its lower jaw instead of its ears?"},{"id":"dolphin-language-overstated","t":"ocean","q":"Why is it wrong to say dolphins talk to each other in a language like ours?"},{"id":"dolphin-male-alliance","t":"ocean","q":"Why do some male dolphins team up in tight pairs or trios for life?"},{"id":"dolphin-melon-organ","t":"ocean","q":"Why does a dolphin have a bulging, fatty lump on its forehead?"},{"id":"dolphin-mirror-test","t":"ocean","q":"Why do dolphins check a mirror to look at themselves?"},{"id":"dolphin-mud-ring-feeding","t":"ocean","q":"Why do dolphins sometimes swim in a circle to build a wall of mud around fish?"},{"id":"dolphin-name-etymology-womb","t":"ocean","q":"Why does the word \"dolphin\" come from an ancient word meaning \"womb\"?"},{"id":"dolphin-newborn-tail-first","t":"ocean","q":"Why is a dolphin calf born tail-first instead of head-first?"},{"id":"dolphin-no-smell","t":"ocean","q":"Why can't dolphins smell anything at all?"},{"id":"dolphin-not-fish-myth","t":"ocean","q":"Why do so many people still think a dolphin is a kind of fish?"},{"id":"dolphin-orca-dialects","t":"ocean","q":"Why do different orca pods have their own distinct call \"dialects\"?"},{"id":"dolphin-orca-largest-dolphin","t":"ocean","q":"Why is the orca, or \"killer whale,\" actually the biggest kind of dolphin?"},{"id":"dolphin-pink-amazon-river","t":"ocean","q":"Why can an Amazon river dolphin turn pink as it grows older?"},{"id":"dolphin-remember-friends-decades","t":"ocean","q":"Why can a dolphin recognise a companion's whistle after twenty years apart?"},{"id":"dolphin-rescue-injured-podmate","t":"ocean","q":"Why do healthy dolphins sometimes hold an injured podmate up to breathe?"},{"id":"dolphin-river-dolphin-poor-eyesight","t":"ocean","q":"Why do some river dolphins have tiny eyes and almost no eyesight?"},{"id":"dolphin-shark-attack-myth","t":"ocean","q":"Why shouldn't you count on a dolphin to save you from a shark?"},{"id":"dolphin-signature-whistle-name","t":"ocean","q":"Why does each dolphin invent its own personal whistle?"},{"id":"dolphin-skin-shed-fast","t":"ocean","q":"Why does a dolphin's skin peel and renew itself every couple of hours?"},{"id":"dolphin-social-grief-mourning","t":"ocean","q":"Why do dolphin mothers sometimes carry a dead calf for days?"},{"id":"dolphin-speed-hydrodynamics","t":"ocean","q":"Why did scientists once think dolphin skin had a magic trick for swimming fast?"},{"id":"dolphin-spinner-spin","t":"ocean","q":"Why does a spinner dolphin spin several times in the air before it lands?"},{"id":"dolphin-sponge-tool-use","t":"ocean","q":"Why do some dolphins wear a sea sponge on their nose while hunting?"},{"id":"dolphin-strand-feeding","t":"ocean","q":"Why do some dolphins deliberately beach themselves to catch fish, then wriggle back?"},{"id":"dolphin-superpod-gathering","t":"ocean","q":"Why do thousands of dolphins sometimes gather into one giant \"superpod\"?"},{"id":"dolphin-teeth-not-chew","t":"ocean","q":"Why do dolphins swallow fish whole instead of chewing them?"},{"id":"dolphin-tuna-net-history","t":"ocean","q":"Why did tuna fishing nets used to trap and kill so many dolphins?"},{"id":"dolphin-unihemispheric-sleep","t":"ocean","q":"Why does a dolphin only ever switch off half its brain to sleep?"},{"id":"dolphin-whistle-vs-click-purpose","t":"ocean","q":"Why does a dolphin use two totally different sounds for two different jobs?"},{"id":"dolphins-leap","t":"ocean","q":"Why do dolphins leap out of the water?"},{"id":"drift-buoys","t":"ocean","q":"Why do scientists deliberately set buoys loose on the sea and just let them drift?"},{"id":"drinking-seawater-danger","t":"ocean","q":"Why can drinking seawater when you're shipwrecked make you more dangerously thirsty, not less?"},{"id":"dumbo-octopus-ear-fins","t":"ocean","q":"Why does the dumbo octopus flap ear-like fins to swim through the deep sea?"},{"id":"eac-strengthening","t":"ocean","q":"Why are tropical fish turning up further south along Australia's coast than they used to?"},{"id":"eel-sargasso","t":"ocean","q":"Why do river eels swim thousands of kilometres out to sea to breed?"},{"id":"ekman-spiral","t":"ocean","q":"Why does water just below the surface drift sideways from the wind blowing above it?"},{"id":"el-nino-global","t":"ocean","q":"Why can warm water off South America dry out farms on the far side of the world?"},{"id":"el-nino-mechanism","t":"ocean","q":"Why can El Niño make Peru's anchovies vanish almost overnight?"},{"id":"el-nino-name","t":"ocean","q":"Why is a huge Pacific Ocean event named after a Christmas baby?"},{"id":"electric-eel","t":"ocean","q":"Why can an electric eel shock you?"},{"id":"elephantfish-electric","t":"ocean","q":"Why do some fish send out weak electric pulses instead of a shock?"},{"id":"enso-unpredictable","t":"ocean","q":"Why can't anyone say exactly when the next El Niño will strike?"},{"id":"estuary-fish-nursery-salinity","t":"ocean","q":"Why do river mouths make such good nurseries for young fish that can't yet handle the open sea?"},{"id":"eyes-sting-ocean","t":"ocean","q":"Why do your eyes sting more in the ocean than in an ordinary swimming pool?"},{"id":"fiddler-crab-salty-mud","t":"ocean","q":"Why do fiddler crabs dig burrows in salty mud instead of living out in the open?"},{"id":"fire-coral-not-coral-sting","t":"ocean","q":"Why does fire coral sting like a jellyfish when it isn't one?"},{"id":"fish-breeding-colours","t":"ocean","q":"Why do male fish often turn brighter colours to find a mate?"},{"id":"fish-cold-blooded","t":"ocean","q":"Why are fish usually called cold-blooded, and is that fair?"},{"id":"fish-colour-change","t":"ocean","q":"Why can some fish change colour in seconds?"},{"id":"fish-colour-vision","t":"ocean","q":"Why can many fish see colours we can't?"},{"id":"fish-countershading","t":"ocean","q":"Why are so many fish dark on top and pale underneath?"},{"id":"fish-dorsal-spines","t":"ocean","q":"Why do some fish have sharp spines on their backs?"},{"id":"fish-external-fertilise","t":"ocean","q":"Why do most fish never actually touch when they make babies?"},{"id":"fish-float-dead","t":"ocean","q":"Why does a dead fish often float belly-up?"},{"id":"fish-gill-rakers","t":"ocean","q":"Why do some fish have comb-like structures in their throats?"},{"id":"fish-gills","t":"ocean","q":"Why don't fish drown?"},{"id":"fish-hearing","t":"ocean","q":"Why can fish hear even though they have no ears you can see?"},{"id":"fish-lateral-line-2","t":"ocean","q":"Why can a fish feel you swim past without looking?"},{"id":"fish-no-eyelids","t":"ocean","q":"Why don't fish have eyelids?"},{"id":"fish-no-scales","t":"ocean","q":"Why don't all fish have scales?"},{"id":"fish-pain","t":"ocean","q":"Why don't scientists agree on whether fish feel pain?"},{"id":"fish-pectoral-fins","t":"ocean","q":"Why do fish have fins on their sides as well as a tail?"},{"id":"fish-s-curve-swim","t":"ocean","q":"Why does a fish's whole body bend into an S shape when it swims?"},{"id":"fish-scale-rings","t":"ocean","q":"Why can scientists tell a fish's age from its scales?"},{"id":"fish-scale-tiles","t":"ocean","q":"Why do fish scales overlap like roof tiles?"},{"id":"fish-scales","t":"ocean","q":"Why do fish have scales?"},{"id":"fish-schools","t":"ocean","q":"Why do fish swim in huge groups?"},{"id":"fish-silver-scales","t":"ocean","q":"Why do so many open-ocean fish look like polished silver?"},{"id":"fish-sleep","t":"ocean","q":"Why do fish \"sleep\" with their eyes open?"},{"id":"fish-slime","t":"ocean","q":"Why are most fish covered in slippery slime?"},{"id":"fish-swim-bladder","t":"ocean","q":"Why doesn't a fish have to keep swimming just to stay at one depth?"},{"id":"fish-tail-shape","t":"ocean","q":"Why do fast-swimming fish usually have a forked tail?"},{"id":"fish-taste-skin","t":"ocean","q":"Why can some fish taste with their skin?"},{"id":"flatfish-eyes","t":"ocean","q":"Why does a flatfish have both eyes on one side of its head?"},{"id":"flying-fish-glide","t":"ocean","q":"Why can flying fish glide so far above the waves?"},{"id":"foam-white-not-clear","t":"ocean","q":"Why does sea foam look white when it's made of nothing but water and air?"},{"id":"freshwater-fish-no-drink","t":"ocean","q":"Why does a freshwater fish never need to take a single sip of water?"},{"id":"freshwater-spring-shimmer","t":"ocean","q":"Why can the water look blurry and shimmering where a freshwater spring bubbles up into the sea?"},{"id":"fringing-barrier-atoll","t":"ocean","q":"Why do some coral reefs hug the coast while others form rings out in the open sea?"},{"id":"frogfish-walk","t":"ocean","q":"Why can a frogfish \"walk\" along the seafloor on its fins?"},{"id":"garbage-patch-gyre-trap","t":"ocean","q":"Why does floating rubbish from a whole ocean basin end up trapped in one small patch?"},{"id":"ghost-nets","t":"ocean","q":"Why do lost fishing nets keep drifting and catching fish for years after they're abandoned?"},{"id":"giant-clam-own-algae","t":"ocean","q":"Why does a giant clam open its huge, colourful mantle to the sun all day?"},{"id":"giant-squid-blue-blood","t":"ocean","q":"Why is giant squid blood blue instead of red?"},{"id":"giant-squid-first-film-2004","t":"ocean","q":"Why wasn't a live giant squid ever filmed in its own deep sea home until 2004?"},{"id":"giant-squid-hard-beak","t":"ocean","q":"Why is the only truly hard part of a giant squid's whole body its beak?"},{"id":"giant-squid-huge-eyes","t":"ocean","q":"Why do giant squid have the biggest eyes in the entire animal kingdom?"},{"id":"giant-squid-sucker-scars","t":"ocean","q":"Why do sperm whales often carry circular scars from giant squid battles?"},{"id":"gill-countercurrent","t":"ocean","q":"Why are fish gills so much better at getting oxygen from water than we'd expect?"},{"id":"glacial-fjord-milky-turquoise","t":"ocean","q":"Why do fjords fed by glacier rivers often look milky turquoise?"},{"id":"goby-shrimp-burrow-partnership","t":"ocean","q":"Why do some nearly blind shrimp share a burrow with a fish that can see perfectly well?"},{"id":"goldfish-memory","t":"ocean","q":"Why is it wrong to say a goldfish only remembers things for three seconds?"},{"id":"green-sea-phytoplankton","t":"ocean","q":"Why do some patches of ocean look green instead of blue or brown?"},{"id":"gulf-stream-europe","t":"ocean","q":"Why is Western Europe milder in winter than Canada at the same latitude?"},{"id":"gulf-stream-speed","t":"ocean","q":"Why can the Gulf Stream add almost ten kilometres an hour to a ship's speed?"},{"id":"gulf-stream-wall","t":"ocean","q":"Why can a sailor feel the exact moment their ship crosses into the Gulf Stream?"},{"id":"gulf-stream-warm","t":"ocean","q":"Why is the Gulf Stream so much warmer than the sea around it?"},{"id":"gulper-eel-stretch-mouth","t":"ocean","q":"Why can the gulper eel open its mouth wider than its own body?"},{"id":"guppy-live-birth","t":"ocean","q":"Why do some fish give birth to live babies instead of laying eggs?"},{"id":"haber-gold-seawater","t":"ocean","q":"Why did a famous scientist secretly try, and fail, to pull gold from seawater?"},{"id":"halocline-layers","t":"ocean","q":"Why does the sea sometimes form invisible layers of water that barely mix?"},{"id":"horizon-vs-feet-colour","t":"ocean","q":"Why can the sea at the horizon look different to the water at your feet?"},{"id":"hot-water-jelly-sting","t":"ocean","q":"Why does hot water help some jellyfish stings more than ice does?"},{"id":"humphead-wrasse-predator","t":"ocean","q":"Why is the humphead wrasse one of the few reef fish that can safely eat crown-of-thorns starfish?"},{"id":"ice-floats","t":"ocean","q":"Why does ice float?"},{"id":"iceberg-blue-old-ice","t":"ocean","q":"Why can some icebergs glow a deep, startling blue?"},{"id":"iceberg-current","t":"ocean","q":"Why do icebergs from Greenland drift straight into busy shipping lanes far to the south?"},{"id":"iceberg-jade-green","t":"ocean","q":"Why do some Antarctic icebergs turn out jade green?"},{"id":"iceberg-white-not-clear","t":"ocean","q":"Why do icebergs usually look white instead of clear like an ice cube?"},{"id":"icefish-antifreeze","t":"ocean","q":"Why don't icefish freeze solid in the coldest ocean water on Earth?"},{"id":"immortal-jellyfish-regrow","t":"ocean","q":"Why can one jellyfish species turn back into a baby instead of dying?"},{"id":"irukandji-tiny-severe","t":"ocean","q":"Why can a jellyfish smaller than your thumbnail cause days of agony?"},{"id":"jelly-babies-two-body-forms","t":"ocean","q":"Why does a jellyfish spend part of its life looking nothing like a jellyfish?"},{"id":"jelly-bloom-increasing","t":"ocean","q":"Why are jellyfish blooms becoming more common in some seas?"},{"id":"jelly-bloom-swarm","t":"ocean","q":"Why can a beach fill with thousands of jellyfish almost overnight?"},{"id":"jelly-clogs-power-station","t":"ocean","q":"Why can a swarm of jellyfish shut down a power station?"},{"id":"jelly-dead-still-stings","t":"ocean","q":"Why can a jellyfish sting you even after it's dead on the sand?"},{"id":"jelly-freshwater-rare","t":"ocean","q":"Why do almost all jellyfish live in the sea and hardly any in lakes or rivers?"},{"id":"jelly-mostly-water-shape","t":"ocean","q":"Why does a jellyfish lose its shape completely once it's out of water?"},{"id":"jelly-no-brain-nerve-net","t":"ocean","q":"Why can a jellyfish hunt and react with no brain at all?"},{"id":"jelly-no-heart-blood","t":"ocean","q":"Why can a jellyfish survive with no heart, blood or gills?"},{"id":"jelly-pee-myth","t":"ocean","q":"Why doesn't peeing on a jellyfish sting actually help?"},{"id":"jelly-senses-no-eyes-ears","t":"ocean","q":"Why can a jellyfish sense light and danger with no eyes or ears at all?"},{"id":"jelly-sting-worse-warm-water","t":"ocean","q":"Why do jellyfish stings happen more often in warm summer water?"},{"id":"jelly-tentacle-count-species","t":"ocean","q":"Why do some jellyfish have four tentacles and others have hundreds?"},{"id":"jelly-torn-tentacle-stings","t":"ocean","q":"Why can a torn-off jellyfish tentacle still sting on its own?"},{"id":"jellyfish","t":"ocean","q":"Why do jellyfish sting?"},{"id":"jellyfish-detachable-glow-arms","t":"ocean","q":"Why do some deep sea jellyfish detach glowing arms when something attacks them?"},{"id":"kuroshio","t":"ocean","q":"Why is Japan's fastest current nicknamed the 'Black Tide'?"},{"id":"la-nina","t":"ocean","q":"Why does La Niña do almost the exact opposite of El Niño?"},{"id":"lagoon-patchwork-colours","t":"ocean","q":"Why can one lagoon show off five or six different shades of blue and green at once?"},{"id":"lionfish-invasive-atlantic","t":"ocean","q":"Why did lionfish become a disaster after turning up in the Atlantic?"},{"id":"lions-mane-tentacle-length","t":"ocean","q":"Why can one jellyfish's tentacles stretch longer than a blue whale?"},{"id":"longshore-drift","t":"ocean","q":"Why does sand slowly creep sideways along a beach, even though waves just seem to go in and out?"},{"id":"lungfish-air","t":"ocean","q":"Why can a lungfish survive out of water for months?"},{"id":"man-o-war-not-jellyfish","t":"ocean","q":"Why isn't a Portuguese man o' war actually a jellyfish?"},{"id":"mangrove-leaf-salt-crystals","t":"ocean","q":"Why do some marsh and mangrove plants grow their own crystals of salt on their leaves?"},{"id":"mangrove-root-salt-filter","t":"ocean","q":"Why can some mangrove trees filter salt out of seawater before it ever reaches their leaves?"},{"id":"marine-iguana-sneeze-salt","t":"ocean","q":"Why do marine iguanas sneeze out crystals of salt?"},{"id":"marine-snow-origin","t":"ocean","q":"Why does it seem to snow constantly in the deep sea?"},{"id":"mediterranean-outflow","t":"ocean","q":"Why does a hidden river of salty water pour out through the Strait of Gibraltar?"},{"id":"mesophotic-reef-twilight","t":"ocean","q":"Why can healthy coral reefs exist far deeper than most divers ever go?"},{"id":"mimic-octopus-reef-camouflage","t":"ocean","q":"Why can one octopus near a reef impersonate several completely different animals?"},{"id":"moon-jelly-mild-sting","t":"ocean","q":"Why does a moon jellyfish's sting barely bother most people?"},{"id":"moonlight-path-sea","t":"ocean","q":"Why does moonlight lay a shimmering path across the sea instead of lighting it evenly?"},{"id":"moray-eel-crevice-hide","t":"ocean","q":"Why do moray eels spend most of the day hiding in narrow reef crevices with just their heads poking out?"},{"id":"moray-eel-mouth","t":"ocean","q":"Why does a moray eel keep opening and closing its mouth?"},{"id":"mudskipper-fins","t":"ocean","q":"Why can a mudskipper use its fins to crawl out of water?"},{"id":"natural-oil-rainbow-sheen","t":"ocean","q":"Why can a rainbow sheen on the sea sometimes have nothing to do with an oil spill?"},{"id":"nematocyst-speed-fire","t":"ocean","q":"Why does a jellyfish sting fire faster than you can blink?"},{"id":"no-outlet-lakes-salty","t":"ocean","q":"Why do lakes with no river flowing out of them always end up salty?"},{"id":"nudibranch-stolen-stinging-cells","t":"ocean","q":"Why can some reef sea slugs sting even though they have no venom glands of their own?"},{"id":"ocean-acidification-coral-skeleton","t":"ocean","q":"Why does extra carbon dioxide in the air make it harder for coral to build its skeleton?"},{"id":"ocean-blue","t":"ocean","q":"Why is the sea blue?"},{"id":"ocean-salt-bury-continents","t":"ocean","q":"Why is there enough salt dissolved in the sea to bury every continent under metres of it?"},{"id":"octopus-argonaut-paper-shell","t":"ocean","q":"Why does a female argonaut octopus carry around a shell that isn't actually a shell?"},{"id":"octopus-arm-brain","t":"ocean","q":"Why can a cut-off octopus arm still crawl and grab things on its own?"},{"id":"octopus-blanket-tiny-male","t":"ocean","q":"Why is a female blanket octopus sometimes 10,000 times heavier than the male of her own species?"},{"id":"octopus-blue-ringed-toxin","t":"ocean","q":"Why is one of the smallest octopuses also one of the most dangerous?"},{"id":"octopus-brain-around-throat","t":"ocean","q":"Why does an octopus have to be careful about what it swallows because of where its brain is?"},{"id":"octopus-camouflage-texture","t":"ocean","q":"Why can an octopus make its own skin look bumpy like coral or spiky like seaweed?"},{"id":"octopus-camouflage-when-sleeping","t":"ocean","q":"Why does a sleeping octopus sometimes change colour and twitch, almost as if it's dreaming?"},{"id":"octopus-coconut-tool","t":"ocean","q":"Why does one small octopus carry coconut shells around with it across the seafloor?"},{"id":"octopus-den-shell-midden","t":"ocean","q":"Why do divers sometimes find a pile of empty shells outside an octopus's den?"},{"id":"octopus-ink-smokescreen","t":"ocean","q":"Why does octopus ink work as more than just a smokescreen?"},{"id":"octopus-mating-at-arms-length","t":"ocean","q":"Why does a male octopus mate from as far away as possible instead of getting close?"},{"id":"octopus-mother-starves","t":"ocean","q":"Why do octopus mothers stop eating and never leave their eggs?"},{"id":"octopus-only-hard-part-beak","t":"ocean","q":"Why can an octopus squeeze its whole body through a gap barely wider than one of its eyes?"},{"id":"octopus-regrow-arm","t":"ocean","q":"Why can an octopus regrow an arm it has lost?"},{"id":"octopus-see-with-skin","t":"ocean","q":"Why can a colour-blind octopus still match the colours of the reef around it so well?"},{"id":"octopus-short-lifespan","t":"ocean","q":"Why do most octopuses only live for one or two years despite being so clever?"},{"id":"octopus-smart","t":"ocean","q":"Why are octopuses so clever?"},{"id":"octopus-suckers-avoid-own-skin","t":"ocean","q":"Why don't an octopus's own suckers grab onto its own arms and skin?"},{"id":"octopus-three-hearts","t":"ocean","q":"Why does an octopus have three hearts instead of one?"},{"id":"octopus-two-arm-walk-disguise","t":"ocean","q":"Why does one octopus walk on just two arms while holding the other six up like plants or a coconut?"},{"id":"oil-spill-rainbow-sheen","t":"ocean","q":"Why does a thin oil spill make the sea shimmer with rainbow colours?"},{"id":"overcast-sea-grey","t":"ocean","q":"Why does the sea often look flat grey under a cloudy sky?"},{"id":"parrotfish-sand-poop","t":"ocean","q":"Why is a parrotfish partly responsible for the white sand on a tropical beach?"},{"id":"penguins-cold","t":"ocean","q":"Why aren't penguins cold?"},{"id":"peru-fishery","t":"ocean","q":"Why does a narrow strip of Peru's coast land one of the biggest fish catches on the planet?"},{"id":"pink-sand-beach-water","t":"ocean","q":"Why does the shallow water at some beaches look faintly pink?"},{"id":"polarised-sunglasses-sea","t":"ocean","q":"Why does the sea suddenly look bluer through polarised sunglasses?"},{"id":"pompeii-worm-heat","t":"ocean","q":"Why can the Pompeii worm survive water hot enough to cook most animals instantly?"},{"id":"pool-blue-glass-clear","t":"ocean","q":"Why does a full swimming pool look blue when the same water in a drinking glass looks clear?"},{"id":"pufferfish-inflate","t":"ocean","q":"Why does a pufferfish gulp water to blow up like a balloon?"},{"id":"rays-fly","t":"ocean","q":"Why do stingrays look like they're flying?"},{"id":"reading-waves","t":"ocean","q":"Why can experienced surfers tell where a wave is going to break before it happens?"},{"id":"red-animals-hide-in-deep-sea","t":"ocean","q":"Why is red one of the best camouflage colours in the deep sea?"},{"id":"red-sea-high-salt","t":"ocean","q":"Why is the Red Sea one of the saltiest seas on Earth?"},{"id":"red-sea-name-bloom","t":"ocean","q":"Why is the Red Sea called red when it usually looks as blue as any other sea?"},{"id":"red-tide-not-a-tide","t":"ocean","q":"Why is a 'red tide' not actually about the tide at all?"},{"id":"reef-calcium-carbonate-build","t":"ocean","q":"Why can a coral reef take thousands of years to grow just a few metres tall?"},{"id":"reef-coastal-protection","t":"ocean","q":"Why do engineers sometimes call a coral reef cheaper than a concrete sea wall?"},{"id":"reef-crest-wave-break","t":"ocean","q":"Why does the roughest, most battered part of a reef sit right at its outer edge?"},{"id":"reef-fish-bright","t":"ocean","q":"Why are so many reef fish brightly coloured if hiding matters?"},{"id":"reef-fraction-of-seafloor","t":"ocean","q":"Why do coral reefs matter so much when they cover such a tiny part of the ocean floor?"},{"id":"reef-not-indestructible","t":"ocean","q":"Why can a reef that survived for thousands of years die within a single human lifetime?"},{"id":"reef-shark-camouflage-countershading","t":"ocean","q":"Why are reef sharks dark on top and pale underneath?"},{"id":"reef-snapping-shrimp-noise","t":"ocean","q":"Why does a healthy coral reef sound like frying bacon underwater?"},{"id":"reef-turquoise-photos-real","t":"ocean","q":"Why do reef photos sometimes look more turquoise than the reef looked in person?"},{"id":"reverse-osmosis-membrane","t":"ocean","q":"Why does modern desalination push seawater through a membrane instead of just boiling it?"},{"id":"rip-current-escape","t":"ocean","q":"Why is swimming parallel to the beach the way to escape a rip, instead of swimming straight back in?"},{"id":"rip-current-form","t":"ocean","q":"Why do rip currents often form in the calmest-looking patch of water on the whole beach?"},{"id":"rip-current-out","t":"ocean","q":"Why does a rip current pull you out to sea rather than pull you under the water?"},{"id":"river-mouth-muddy-brown","t":"ocean","q":"Why does the sea turn muddy brown for kilometres around a big river mouth?"},{"id":"river-water-not-salty","t":"ocean","q":"Why does river water taste fresh when rivers are what make the sea salty?"},{"id":"rock-pools","t":"ocean","q":"Why are there rock pools?"},{"id":"rogue-wave-current","t":"ocean","q":"Why are rogue waves especially common where a wave train meets a strong opposing ocean current?"},{"id":"rogue-wave-interference","t":"ocean","q":"Why can two ordinary waves combine to make one wave twice as tall?"},{"id":"rogue-wave-real","t":"ocean","q":"Why did sailors' stories of monster 'rogue waves' turn out to be true?"},{"id":"rov-robot-explorers","t":"ocean","q":"Why do scientists send robots instead of people to explore the deepest parts of the ocean?"},{"id":"salmon-home-river","t":"ocean","q":"Why can salmon find their way back to the exact river they were born in?"},{"id":"salt-float","t":"ocean","q":"Why is it easier to float in the sea than in a pool?"},{"id":"salt-harvest-hot-dry","t":"ocean","q":"Why is sea salt harvested in hot, flat, dry places rather than everywhere along a coast?"},{"id":"salt-marsh-rotten-egg-smell","t":"ocean","q":"Why does salt marsh mud often smell like rotten eggs?"},{"id":"salt-marsh-tide-flood","t":"ocean","q":"Why do salt marshes flood and drain twice a day?"},{"id":"salt-melts-ice-path","t":"ocean","q":"Why does scattering salt on an icy footpath make the ice melt?"},{"id":"salt-pond-pink","t":"ocean","q":"Why do some salt evaporation ponds turn shocking pink?"},{"id":"salt-same-recipe-everywhere","t":"ocean","q":"Why does seawater have almost the same mix of salts everywhere, even when its total saltiness differs?"},{"id":"salt-water-boil-myth","t":"ocean","q":"Why doesn't a pinch of salt actually make a pot of water boil any faster?"},{"id":"salt-wedge-drought-river","t":"ocean","q":"Why can salty water creep upstream along a riverbed during a long drought?"},{"id":"salt-wilts-cabbage-leaf","t":"ocean","q":"Why does sprinkling salt on a lettuce or cabbage leaf make it go limp and watery?"},{"id":"saltbush-silvery-grey","t":"ocean","q":"Why do some salt marsh plants look silvery-grey instead of ordinary green?"},{"id":"saltwater-fish-drink","t":"ocean","q":"Why must a saltwater fish drink seawater constantly just to survive?"},{"id":"samphire-salt-storage","t":"ocean","q":"Why can some marsh plants grow with their roots sitting in salty water without shrivelling up?"},{"id":"sargasso-sea","t":"ocean","q":"Why is the Sargasso Sea the only sea on Earth with no coastline at all?"},{"id":"satellite-ocean-colour","t":"ocean","q":"Why can satellites map the whole ocean's colour without a single ship taking a sample?"},{"id":"sea-blue-no-sky","t":"ocean","q":"Why does seawater still look blue even scooped into a white bucket with no sky in sight?"},{"id":"sea-currents","t":"ocean","q":"Why does the sea have currents?"},{"id":"sea-fan-current-filter","t":"ocean","q":"Why do sea fans grow flat and wide instead of round and bushy?"},{"id":"sea-foam","t":"ocean","q":"Why is there foam on the beach?"},{"id":"sea-freeze-below-zero","t":"ocean","q":"Why does the sea need to get colder than 0°C before it freezes?"},{"id":"sea-ice-white-ocean-dark","t":"ocean","q":"Why does floating sea ice look white while open water beside it looks almost black?"},{"id":"sea-lice-jelly-larvae-rash","t":"ocean","q":"Why can an itchy rash appear under swimwear with no jellyfish in sight?"},{"id":"sea-not-saltier-forever","t":"ocean","q":"Why doesn't the sea get saltier and saltier every single year?"},{"id":"sea-plastic","t":"ocean","q":"Why is there plastic in the sea?"},{"id":"sea-salt-same-as-table-salt","t":"ocean","q":"Why is sea salt, gram for gram, basically the same as ordinary table salt despite costing so much more?"},{"id":"sea-silver-sunset","t":"ocean","q":"Why can the sea suddenly turn silver near sunrise or sunset?"},{"id":"sea-turtle-reef-cleaning","t":"ocean","q":"Why do sea turtles visit the same reef cleaning spot again and again?"},{"id":"seabird-salt-gland","t":"ocean","q":"Why do seabirds like albatrosses have a special gland just for getting rid of salt?"},{"id":"seafloor-less-mapped-than-moon","t":"ocean","q":"Why do we know the surface of the Moon better than the bottom of our own ocean?"},{"id":"seagrass-darker-patches","t":"ocean","q":"Why do dark patches under clear water usually mean seagrass rather than a hole?"},{"id":"seahorse-dad","t":"ocean","q":"Why do seahorse fathers carry the babies?"},{"id":"seahorse-dads","t":"ocean","q":"Why do seahorse dads have the babies?"},{"id":"seawater-conducts-electricity","t":"ocean","q":"Why does seawater conduct electricity so much better than a freshwater lake?"},{"id":"seawater-denser","t":"ocean","q":"Why is seawater heavier than fresh water, litre for litre?"},{"id":"seaweed-roots","t":"ocean","q":"Why doesn't seaweed have roots?"},{"id":"seiche-harbour","t":"ocean","q":"Why can a harbour or lake keep sloshing back and forth for hours after a storm has passed?"},{"id":"seven-seas-not-colours","t":"ocean","q":"Why aren't the 'Seven Seas' seven different colours of water?"},{"id":"shallows-turquoise","t":"ocean","q":"Why do tropical shallows look turquoise instead of deep blue?"},{"id":"shark-ampullae-pores","t":"ocean","q":"Why does a shark's snout look freckled with tiny dark spots?"},{"id":"shark-angel-buried","t":"ocean","q":"Why does an angel shark bury itself in the sand to hunt?"},{"id":"shark-attack-rarity","t":"ocean","q":"Why is being hurt by a shark one of the least likely things at the beach?"},{"id":"shark-basking-filter","t":"ocean","q":"Why does the second-biggest fish in the sea have almost no visible teeth?"},{"id":"shark-bite-force","t":"ocean","q":"Why is a bull shark's bite so strong for its size?"},{"id":"shark-bite-metal","t":"ocean","q":"Why do sharks sometimes bite boat propellers or metal cages?"},{"id":"shark-blue-wanderer","t":"ocean","q":"Why can a blue shark cross an entire ocean in a single journey?"},{"id":"shark-boldness-personality","t":"ocean","q":"Why do some sharks act consistently bolder than others of the same species?"},{"id":"shark-bull-freshwater","t":"ocean","q":"Why can a bull shark swim hundreds of kilometres up a freshwater river?"},{"id":"shark-cage-diving-chum","t":"ocean","q":"Why is dropping chum into the water during shark cage diving controversial?"},{"id":"shark-cancer-myth","t":"ocean","q":"Why did people used to think sharks couldn't get cancer?"},{"id":"shark-cartilage-skeleton","t":"ocean","q":"Why is a shark's skeleton made of cartilage instead of bone?"},{"id":"shark-cartilage-turning","t":"ocean","q":"Why can a shark twist and turn so much sharper than most bony fish?"},{"id":"shark-clasper-mating","t":"ocean","q":"Why do male sharks have two long, finger-like structures near their tail?"},{"id":"shark-colour-vision","t":"ocean","q":"Why might a shark see the whole ocean in shades of grey?"},{"id":"shark-cookiecutter-bite","t":"ocean","q":"Why do round plug-shaped bites sometimes show up on whales and submarines?"},{"id":"shark-deep-sea-dark","t":"ocean","q":"Why do some sharks live so deep they've never seen sunlight?"},{"id":"shark-dorsal-fin-function","t":"ocean","q":"Why does a shark have a tall fin sticking straight up from its back?"},{"id":"shark-eggs-vs-live","t":"ocean","q":"Why do some sharks lay eggs while others give birth to live pups?"},{"id":"shark-electro-buried-fish","t":"ocean","q":"Why can a shark find a fish hiding under the sand without seeing it?"},{"id":"shark-epaulette-oxygen","t":"ocean","q":"Why can an epaulette shark survive in water with almost no oxygen?"},{"id":"shark-epaulette-walk","t":"ocean","q":"Why can an epaulette shark 'walk' across a reef flat out of the water?"},{"id":"shark-eyeshine-tapetum","t":"ocean","q":"Why do shark eyes sometimes glow when a torch shines on them at night?"},{"id":"shark-finning","t":"ocean","q":"Why is cutting the fins off a shark and dumping the rest so damaging?"},{"id":"shark-frilled-ancient-look","t":"ocean","q":"Why does the frilled shark look more like an eel than a typical shark?"},{"id":"shark-glow-dark","t":"ocean","q":"Why do some sharks glow in the dark?"},{"id":"shark-goblin-jaw","t":"ocean","q":"Why does the goblin shark have a jaw that shoots forward out of its face?"},{"id":"shark-great-white-breach","t":"ocean","q":"Why do great white sharks sometimes leap right out of the water?"},{"id":"shark-great-white-warm","t":"ocean","q":"Why is a great white shark's body warmer than the water around it?"},{"id":"shark-greenland-age","t":"ocean","q":"Why can a Greenland shark live for four hundred years?"},{"id":"shark-greenland-eye-parasite","t":"ocean","q":"Why do many Greenland sharks swim around with a parasite dangling from each eye?"},{"id":"shark-greenland-slow","t":"ocean","q":"Why do Greenland sharks swim so slowly?"},{"id":"shark-hammerhead-schooling","t":"ocean","q":"Why do scalloped hammerhead sharks gather in huge daytime schools?"},{"id":"shark-hammerhead-shape","t":"ocean","q":"Why do hammerhead sharks have such a strangely shaped head?"},{"id":"shark-hammerhead-vision","t":"ocean","q":"Why can a hammerhead shark see almost all the way around itself?"},{"id":"shark-hearing-low-frequency","t":"ocean","q":"Why can a shark hear a struggling fish from far away before it can see or smell it?"},{"id":"shark-lateral-line","t":"ocean","q":"Why can a shark feel a fish splashing nearby without seeing, smelling or hearing it at all?"},{"id":"shark-litter-size","t":"ocean","q":"Why do some sharks have just two pups while others have dozens?"},{"id":"shark-liver-oil","t":"ocean","q":"Why do sharks have such an enormous, oily liver?"},{"id":"shark-living-fossil-myth","t":"ocean","q":"Why is calling a shark a 'living fossil' a little bit misleading?"},{"id":"shark-magnetic-navigation","t":"ocean","q":"Why can a shark navigate thousands of kilometres of open ocean with no landmarks at all?"},{"id":"shark-mako-speed","t":"ocean","q":"Why is the shortfin mako the fastest shark in the ocean?"},{"id":"shark-megalodon-size-teeth","t":"ocean","q":"Why can scientists estimate megalodon's size from just its teeth?"},{"id":"shark-megamouth-rare","t":"ocean","q":"Why has the megamouth shark only ever been seen a few hundred times?"},{"id":"shark-mermaids-purse","t":"ocean","q":"Why do little leathery pouches sometimes wash up on the beach?"},{"id":"shark-mistaken-identity","t":"ocean","q":"Why do sharks sometimes bite surfers by mistake?"},{"id":"shark-net-drumline","t":"ocean","q":"Why do shark nets at some beaches catch far more than sharks?"},{"id":"shark-nictitating-membrane","t":"ocean","q":"Why do some sharks roll their eyes back while others blink a see-through eyelid instead?"},{"id":"shark-no-swim-bladder","t":"ocean","q":"Why do most sharks sink if they stop swimming forward?"},{"id":"shark-nose-punch-myth","t":"ocean","q":"Why is 'punch a shark in the nose' more myth than solid advice?"},{"id":"shark-nurse-suction-feeding","t":"ocean","q":"Why can a nurse shark suck a hidden fish straight out of a crack in the rocks?"},{"id":"shark-nursery-mangrove","t":"ocean","q":"Why do baby sharks often grow up in mangrove forests instead of the open sea?"},{"id":"shark-older-than-trees","t":"ocean","q":"Why are sharks older than trees?"},{"id":"shark-port-jackson-egg-spiral","t":"ocean","q":"Why is a Port Jackson shark's egg case shaped like a corkscrew?"},{"id":"shark-pup-cannibal-womb","t":"ocean","q":"Why do some baby sharks eat their brothers and sisters before they're born?"},{"id":"shark-pup-no-parents","t":"ocean","q":"Why do shark pups get no care at all from their parents?"},{"id":"shark-pyjama-catshark-curl","t":"ocean","q":"Why does a pyjama shark curl into a tight ball when it feels threatened?"},{"id":"shark-reef-health","t":"ocean","q":"Why do healthy coral reefs need sharks patrolling them?"},{"id":"shark-remora-hitchhike","t":"ocean","q":"Why do small fish stick themselves to the underside of a shark?"},{"id":"shark-requiem-family","t":"ocean","q":"Why do so many different-looking sharks belong to the very same family?"},{"id":"shark-sawshark-vs-sawfish","t":"ocean","q":"Why do people often mix up sawsharks with sawfish?"},{"id":"shark-sense-heartbeat","t":"ocean","q":"Why can a shark sense a heartbeat without touching or seeing anything?"},{"id":"shark-silky-schools","t":"ocean","q":"Why do silky sharks gather in large schools out in the open ocean?"},{"id":"shark-skin-cut","t":"ocean","q":"Why can rubbing a shark the wrong way graze your skin?"},{"id":"shark-skin-no-algae","t":"ocean","q":"Why doesn't a shark's skin get covered in algae the way a whale's often does?"},{"id":"shark-skin-sandpaper","t":"ocean","q":"Why does shark skin feel like sandpaper?"},{"id":"shark-skin-swimsuits","t":"ocean","q":"Why did swimsuit makers once copy the pattern on shark skin?"},{"id":"shark-smell-blood","t":"ocean","q":"Why can't a shark smell a single drop of blood across a swimming pool?"},{"id":"shark-smell-stereo","t":"ocean","q":"Why can a shark smell in stereo?"},{"id":"shark-smell-zigzag","t":"ocean","q":"Why do sharks swim in a zigzag when they're tracking down a smell?"},{"id":"shark-spiracle-breathe","t":"ocean","q":"Why do nurse sharks have a small hole behind each eye?"},{"id":"shark-spiral-valve-intestine","t":"ocean","q":"Why does a shark's intestine look like a tightly wound spiral staircase inside?"},{"id":"shark-stomach-eversion","t":"ocean","q":"Why can a shark turn its own stomach inside out through its mouth?"},{"id":"shark-tail-heterocercal","t":"ocean","q":"Why is the top half of a shark's tail bigger than the bottom half?"},{"id":"shark-teeth-beach","t":"ocean","q":"Why do shark teeth turn up on beaches more often than shark bones?"},{"id":"shark-teeth-conveyor","t":"ocean","q":"Why do sharks never run out of teeth?"},{"id":"shark-teeth-fossil-black","t":"ocean","q":"Why are fossil shark teeth black instead of white?"},{"id":"shark-teeth-no-roots","t":"ocean","q":"Why don't shark teeth have roots like human teeth?"},{"id":"shark-teeth-shapes","t":"ocean","q":"Why are shark teeth shaped so differently between species?"},{"id":"shark-teeth-tool-history","t":"ocean","q":"Why did some Pacific Island cultures fit sharp shark teeth onto wooden weapons?"},{"id":"shark-thresher-tail","t":"ocean","q":"Why does a thresher shark have a tail as long as its whole body?"},{"id":"shark-tiger-diet","t":"ocean","q":"Why will a tiger shark eat almost anything it finds?"},{"id":"shark-vertebrae-growth-rings","t":"ocean","q":"Why can cutting open a shark's spine reveal exactly how old it is?"},{"id":"shark-whale-harmless","t":"ocean","q":"Why is the biggest fish in the sea completely harmless to people?"},{"id":"shark-whale-plankton-mouth","t":"ocean","q":"Why does a whale shark bother filtering food it can barely even see?"},{"id":"shark-whale-satellite-tag","t":"ocean","q":"Why do scientists attach satellite tags to whale sharks?"},{"id":"shark-whale-spots-fingerprint","t":"ocean","q":"Why is every whale shark's spot pattern different, like a fingerprint?"},{"id":"shark-wobbegong-camouflage","t":"ocean","q":"Why is a wobbegong shark almost invisible lying on the sea floor?"},{"id":"shark-zebra-stripes-spots","t":"ocean","q":"Why does a zebra shark change from stripes to spots as it grows up?"},{"id":"sharks-swim","t":"ocean","q":"Why do sharks never stop swimming?"},{"id":"shell-sound","t":"ocean","q":"Why can you hear the sea in a shell?"},{"id":"shipping-routes-currents","t":"ocean","q":"Why do big ships bend their route across an ocean instead of sailing it dead straight?"},{"id":"shore-break","t":"ocean","q":"Why do some beaches have waves that dump right at the water's edge instead of breaking further out?"},{"id":"shore-break-danger","t":"ocean","q":"Why is a dumping shore break more likely to hurt your neck than a wave breaking further out?"},{"id":"snorkel-mask-sea-clearer","t":"ocean","q":"Why does the sea look clearer through a snorkelling mask than with bare eyes underwater?"},{"id":"sofar-sound-channel","t":"ocean","q":"Why can a whale's call travel for thousands of kilometres through a hidden layer of the ocean?"},{"id":"soft-coral-no-hard-skeleton","t":"ocean","q":"Why do some corals sway freely in the current instead of forming solid, permanent structures?"},{"id":"somali-current-reversal","t":"ocean","q":"Why does one ocean current completely reverse direction, twice a year?"},{"id":"sperm-whale-long-dive","t":"ocean","q":"Why can a sperm whale hold its breath for over an hour to hunt in the deep sea?"},{"id":"squid-arm-suckers-teeth-rings","t":"ocean","q":"Why do the suckers on some squid arms have hard little teeth or rings instead of being smooth?"},{"id":"squid-bobtail-glowing-bacteria","t":"ocean","q":"Why does a tiny bobtail squid keep living bacteria glowing in a pouch under its body?"},{"id":"squid-camera-eye-convergent","t":"ocean","q":"Why does a squid's eye look so much like a human eye, even though squid and humans are barely related?"},{"id":"squid-chromatophore-neural-control","t":"ocean","q":"Why can a squid change its whole body colour in under a second, faster than any chameleon?"},{"id":"squid-color-blind-flashy-signals","t":"ocean","q":"Why do many squid flash bright, colourful patterns at each other if most squid cannot even see colour?"},{"id":"squid-flying-fish-mimicry","t":"ocean","q":"Why do some squid leap out of the ocean and glide through the air like flying fish?"},{"id":"squid-gladius-internal-pen","t":"ocean","q":"Why does a squid have a thin, flexible strip inside its body instead of a shell?"},{"id":"squid-humboldt-cooperative-hunt","t":"ocean","q":"Why do Humboldt squid hunt in flashing red and white groups, sometimes turning on their own kind?"},{"id":"squid-ink-decoy-blob","t":"ocean","q":"Why does a fleeing squid sometimes leave behind an ink blob shaped roughly like itself?"},{"id":"squid-jet-propulsion-speed","t":"ocean","q":"Why can a squid outswim almost every fish in the sea over a short burst?"},{"id":"squid-photophores-counter-illumination","t":"ocean","q":"Why do some deep-water squid glow faintly on their underside, matching light from far above?"},{"id":"squid-schooling-color-signals","t":"ocean","q":"Why do some squid flash changing colour patterns while swimming together in a group?"},{"id":"squid-statocyst-balance-organ","t":"ocean","q":"Why doesn't a squid get dizzy or lose track of which way is up while jetting around in open water?"},{"id":"squid-two-tentacles-eight-arms","t":"ocean","q":"Why does a squid have two limbs longer than the other eight, tipped with extra suckers?"},{"id":"squid-vampire-marine-snow-diet","t":"ocean","q":"Why does the vampire squid eat drifting scraps instead of hunting other animals like its relatives?"},{"id":"starfish-arms","t":"ocean","q":"Why can a starfish grow a new arm?"},{"id":"stinger-suit-lycra","t":"ocean","q":"Why do swimmers wear full-body suits in tropical northern Australia?"},{"id":"stingray-barb-tail","t":"ocean","q":"Why does a stingray carry its weapon on its tail instead of near its mouth?"},{"id":"stingray-not-aggressive","t":"ocean","q":"Why do stingray stings almost always happen by accident?"},{"id":"stonefish-camouflage-sting","t":"ocean","q":"Why does the world's most painful sting come from a fish disguised as a rock?"},{"id":"storm-sediment-brown-days-after","t":"ocean","q":"Why can the sea stay brown for days after a storm has completely passed?"},{"id":"storm-surf-brown-grey","t":"ocean","q":"Why does the sea turn brownish grey during a big storm?"},{"id":"submarine-round-hull","t":"ocean","q":"Why do submarines and deep sea vessels need thick, rounded hulls to survive the deep?"},{"id":"subpolar-gyre","t":"ocean","q":"Why does one part of the North Atlantic spin one way and the part right next to it spin the opposite way?"},{"id":"sunfish-eats-jellyfish","t":"ocean","q":"Why does the giant ocean sunfish eat mostly jellyfish?"},{"id":"super-coral-heat-tolerance","t":"ocean","q":"Why are scientists searching reefs for coral that can already cope with hot water?"},{"id":"surf-lift-forward","t":"ocean","q":"Why does a breaking wave push a surfboard forward when the water further out barely moves that way at all?"},{"id":"surf-paddle-catch","t":"ocean","q":"Why do surfers paddle hard just before a wave arrives instead of waiting for it to lift them?"},{"id":"surf-sound-hiss","t":"ocean","q":"Why does the sea keep hissing after a wave has already crashed and pulled back?"},{"id":"surf-sound-roar","t":"ocean","q":"Why does breaking surf make such a loud roaring sound?"},{"id":"table-salt-underground-mines","t":"ocean","q":"Why does most table salt come from underground mines rather than straight from today's sea?"},{"id":"telescope-fish-tube-eyes","t":"ocean","q":"Why do some deep sea fish have tube-shaped eyes pointing straight up?"},{"id":"tides","t":"ocean","q":"Why does the sea go in and out?"},{"id":"trieste-1960-dive","t":"ocean","q":"Why did it take until 1960 for anyone to reach the deepest point in the ocean?"},{"id":"tsunami-drawback","t":"ocean","q":"Why does the sea sometimes drain away from the beach just before a tsunami hits?"},{"id":"tsunami-earthquake","t":"ocean","q":"Why do earthquakes under the sea cause tsunamis?"},{"id":"tsunami-grow-shallow","t":"ocean","q":"Why can a tsunami be barely noticeable out at sea but grow into a towering wave near the coast?"},{"id":"tsunami-landslide","t":"ocean","q":"Why can an underwater landslide or a volcanic eruption cause a tsunami, just like an earthquake?"},{"id":"tsunami-not-tide","t":"ocean","q":"Why is a tsunami not really a 'tidal wave', even though people used to call it that?"},{"id":"tsunami-word","t":"ocean","q":"Why is a tsunami named after a Japanese word meaning 'harbour wave'?"},{"id":"tube-worm-no-gut","t":"ocean","q":"Why do giant tube worms have no mouth or stomach?"},{"id":"tuna-warm-blood","t":"ocean","q":"Why can some tuna keep parts of their body warmer than the sea around them?"},{"id":"turtle-eats-jellyfish","t":"ocean","q":"Why can sea turtles eat jellyfish without getting stung?"},{"id":"turtle-salty-tears","t":"ocean","q":"Why can a sea turtle look like it's crying, even when nothing at all is wrong?"},{"id":"turtles-beach","t":"ocean","q":"Why do sea turtles come back to the beach where they hatched?"},{"id":"underwater-colours-fade-with-depth","t":"ocean","q":"Why do bright colours fade to grey the deeper you dive?"},{"id":"upside-down-jellyfish-mucus","t":"ocean","q":"Why does one jellyfish lie upside down and sting the water around it?"},{"id":"upwelling-feeds-life","t":"ocean","q":"Why do fishermen call upwelling water the sea's own fertiliser?"},{"id":"upwelling-mechanism","t":"ocean","q":"Why does wind blowing along a coastline drag cold water up from the deep?"},{"id":"urchin-algae-grazer","t":"ocean","q":"Why can too few sea urchins on a reef let seaweed smother the coral?"},{"id":"vampire-squid-inside-out","t":"ocean","q":"Why does the vampire squid turn itself inside out instead of squirting ink?"},{"id":"vent-chemosynthesis-bacteria","t":"ocean","q":"Why do vent bacteria make food out of chemicals instead of sunlight?"},{"id":"vent-chimney-lifespan","t":"ocean","q":"Why can a single hydrothermal vent chimney vanish again within just a few decades?"},{"id":"vent-discovery-1977","t":"ocean","q":"Why didn't scientists know hydrothermal vents even existed until 1977?"},{"id":"vent-ecosystem-sunless","t":"ocean","q":"Why can whole animal communities thrive around hydrothermal vents with no sunlight at all?"},{"id":"vent-shrimp-back-eyes","t":"ocean","q":"Why do some vent shrimp have eyes on their backs instead of their heads?"},{"id":"vinegar-jelly-sting-works","t":"ocean","q":"Why does vinegar stop some jellyfish stings from firing more venom?"},{"id":"viperfish-oversized-teeth","t":"ocean","q":"Why are a viperfish's teeth too big to fit inside its own closed mouth?"},{"id":"volcanic-vents-salt","t":"ocean","q":"Why do underwater volcanoes help make the ocean salty too?"},{"id":"volcano-sea-colour-change","t":"ocean","q":"Why can the sea near an underwater volcano suddenly change colour?"},{"id":"wave-across-ocean-shape","t":"ocean","q":"Why do choppy, messy waves near a storm turn into smooth, evenly-spaced swell far away?"},{"id":"wave-align-beach","t":"ocean","q":"Why do waves always end up lining up with the beach, no matter which way they arrive?"},{"id":"wave-barrel","t":"ocean","q":"Why do some big waves curl over into a hollow tube as they break?"},{"id":"wave-bigger-somewhere","t":"ocean","q":"Why are some beaches famous for giant waves while a beach nearby stays almost flat?"},{"id":"wave-break-shallow","t":"ocean","q":"Why do waves break when they reach the shallows near a beach?"},{"id":"wave-buoy-bob","t":"ocean","q":"Why does a floating buoy mostly bob up and down instead of surfing all the way to shore?"},{"id":"wave-erosion-air","t":"ocean","q":"Why can the air trapped by a crashing wave actually blast pieces of rock apart?"},{"id":"wave-erosion-cliff","t":"ocean","q":"Why do waves carve caves and arches into solid rock cliffs?"},{"id":"wave-fetch","t":"ocean","q":"Why does the stretch of open water the wind blows across change how big the waves get?"},{"id":"wave-height-wind-speed","t":"ocean","q":"Why do stronger winds make waves taller, not just faster?"},{"id":"wave-orbit-depth","t":"ocean","q":"Why does diving down under a big wave feel so much calmer than staying on the surface?"},{"id":"wave-peel","t":"ocean","q":"Why does a wave peel sideways along a point instead of breaking all at once?"},{"id":"wave-period","t":"ocean","q":"Why does the gap in time between one wave crest and the next tell you how powerful a swell is?"},{"id":"wave-power","t":"ocean","q":"Why are engineers trying to turn the up-and-down motion of waves into electricity?"},{"id":"wave-power-hard","t":"ocean","q":"Why is it so much harder to harvest useful energy from ocean waves than from wind?"},{"id":"wave-refraction-headland","t":"ocean","q":"Why do waves bend around a rocky headland and end up hitting it from several sides at once?"},{"id":"wave-set-biggest","t":"ocean","q":"Why is the biggest wave in a set usually not the very first one to arrive?"},{"id":"wave-sets","t":"ocean","q":"Why do waves arrive in groups, with a calmer gap in between?"},{"id":"wave-standing-bath","t":"ocean","q":"Why can rocking gently in a bathtub make the water slosh higher and higher?"},{"id":"wave-steepness-break-type","t":"ocean","q":"Why do some waves spill gently while others crash down all at once?"},{"id":"wave-swell-travel","t":"ocean","q":"Why can swell from a storm thousands of kilometres away reach a beach on a calm, windless day?"},{"id":"wave-water-stays","t":"ocean","q":"Why doesn't the actual water in a wave travel all the way across the ocean?"},{"id":"waves","t":"ocean","q":"Why does the sea have waves?"},{"id":"weever-fish-buried-sting","t":"ocean","q":"Why do bare feet sometimes get stung by a fish nobody saw?"},{"id":"western-intensification","t":"ocean","q":"Why is the Gulf Stream a narrow, racing ribbon while the current across from it is wide and slow?"},{"id":"wetsuit-stops-most-stings","t":"ocean","q":"Why does a wetsuit block most jellyfish stings but not all?"},{"id":"whale-artery-swim-myth","t":"ocean","q":"Why can't you actually swim through a blue whale's main artery, even though people say you can?"},{"id":"whale-baleen-comb","t":"ocean","q":"Why do some whales have a mouth full of bristly combs instead of teeth?"},{"id":"whale-beaked-deep-dive","t":"ocean","q":"Why can a beaked whale dive deeper than any other diving mammal?"},{"id":"whale-beluga-melon","t":"ocean","q":"Why does a beluga whale have a bulging, squishy forehead?"},{"id":"whale-blow-not-water","t":"ocean","q":"Why does a whale's blow look like a fountain of water shooting into the air?"},{"id":"whale-blow-shape-id","t":"ocean","q":"Why can whale-watchers identify a species just from the shape of its blow?"},{"id":"whale-blowhole-not-mouth","t":"ocean","q":"Why does a whale breathe through a hole on top of its head instead of its mouth?"},{"id":"whale-blowhole-number","t":"ocean","q":"Why do some whales have one blowhole and others have two?"},{"id":"whale-blubber-insulation","t":"ocean","q":"Why does a whale wear a thick layer of fat instead of fur to stay warm?"},{"id":"whale-blue-loudest","t":"ocean","q":"Why is it misleading to say a blue whale's call is louder than a jet engine?"},{"id":"whale-bowhead-ice-skull","t":"ocean","q":"Why does a bowhead whale have a skull shaped like the front of a ship?"},{"id":"whale-bowhead-lifespan","t":"ocean","q":"Why can a bowhead whale live longer than 200 years?"},{"id":"whale-brain-big","t":"ocean","q":"Why does a whale have one of the biggest brains of any animal, and what is it for?"},{"id":"whale-breaching","t":"ocean","q":"Why does a whale leap almost entirely out of the water and crash back down?"},{"id":"whale-bubble-net","t":"ocean","q":"Why do humpback whales blow rings of bubbles before they attack a shoal of fish?"},{"id":"whale-callosities","t":"ocean","q":"Why do right whales have rough white patches on their heads that aren't scars?"},{"id":"whale-crushed-on-land","t":"ocean","q":"Why can a beached whale be in danger just from its own weight?"},{"id":"whale-earwax-plug","t":"ocean","q":"Why can scientists read a whale's whole life story from a plug of earwax?"},{"id":"whale-fall-decades","t":"ocean","q":"Why can a dead whale sinking to the seafloor feed a community of animals for decades?"},{"id":"whale-fin-asymmetric","t":"ocean","q":"Why is a fin whale's jaw white on one side and dark on the other?"},{"id":"whale-flipper-fingers","t":"ocean","q":"Why does a whale's flipper contain finger bones like a human hand?"},{"id":"whale-fluke-horizontal","t":"ocean","q":"Why does a whale's tail move up and down instead of side to side like a fish's?"},{"id":"whale-fluke-id","t":"ocean","q":"Why can scientists tell individual whales apart just from a photo of their tail?"},{"id":"whale-grey-mud-feeding","t":"ocean","q":"Why does a grey whale roll onto its side and dig through mud on the seafloor?"},{"id":"whale-hearing-jaw","t":"ocean","q":"Why does a whale hear through its jawbone instead of an ear on the outside of its head?"},{"id":"whale-hunted-recovery","t":"ocean","q":"Why did whale numbers crash so badly, and why are some kinds recovering now?"},{"id":"whale-lunge-feeding","t":"ocean","q":"Why does a whale's throat balloon out to several times its normal size when it feeds?"},{"id":"whale-mammal-not-fish","t":"ocean","q":"Why is a whale a mammal and not a fish?"},{"id":"whale-migration","t":"ocean","q":"Why does a grey whale travel further each year than almost any other mammal on Earth?"},{"id":"whale-milk-fat","t":"ocean","q":"Why is whale milk almost too thick to just pour, more like toothpaste than milk?"},{"id":"whale-minke-smallest","t":"ocean","q":"Why is the minke whale the smallest of the great baleen whales?"},{"id":"whale-narwhal-tusk","t":"ocean","q":"Why does a narwhal grow one long spiral tusk instead of ordinary teeth?"},{"id":"whale-nasal-clicks","t":"ocean","q":"Why do toothed whales make clicking sounds through their nose instead of their throat?"},{"id":"whale-no-fur","t":"ocean","q":"Why do whales have almost no hair, when every other mammal grows some?"},{"id":"whale-nursing-underwater","t":"ocean","q":"Why doesn't a baby whale choke drinking milk underwater?"},{"id":"whale-right-whale-name","t":"ocean","q":"Why is a \"right whale\" called that?"},{"id":"whale-sei-speed","t":"ocean","q":"Why can a sei whale outswim almost every other big whale in a short sprint?"},{"id":"whale-single-calf","t":"ocean","q":"Why does a whale almost always have just one baby at a time?"},{"id":"whale-spermaceti","t":"ocean","q":"Why does a sperm whale carry a giant tank of waxy oil inside its head?"},{"id":"whale-spy-hop","t":"ocean","q":"Why does a whale sometimes poke just its head straight up out of the water?"},{"id":"whale-stranding","t":"ocean","q":"Why do healthy whales sometimes swim onto a beach and get stranded?"},{"id":"whale-teeth-diverse","t":"ocean","q":"Why do toothed whales have such wildly different numbers and shapes of teeth?"},{"id":"whale-tongue-weight","t":"ocean","q":"Why can a blue whale's tongue weigh as much as an elephant?"},{"id":"whale-two-groups","t":"ocean","q":"Why are whales split into two completely different kinds?"},{"id":"whale-vertical-sleep","t":"ocean","q":"Why do sperm whales sometimes sleep floating upright, motionless, just under the surface?"},{"id":"whale-vestigial-legs","t":"ocean","q":"Why does a whale skeleton contain tiny leftover leg bones it never uses?"},{"id":"whales-huge","t":"ocean","q":"Why are whales so big?"},{"id":"whales-sing","t":"ocean","q":"Why do whales sing?"},{"id":"white-sand-bright-water","t":"ocean","q":"Why does water over white sand look far brighter than water over dark rock?"},{"id":"white-sea-name-ice","t":"ocean","q":"Why is Russia's White Sea named for its colour?"},{"id":"whitecaps","t":"ocean","q":"Why do whitecaps appear on the sea once the wind picks up?"},{"id":"yellow-sea-name-silt","t":"ocean","q":"Why is the Yellow Sea actually yellow?"},{"id":"yeti-crab-hairy-arms","t":"ocean","q":"Why does the yeti crab wave its own hairy arms over hydrothermal vent water?"},{"id":"zombie-worm-bone-drill","t":"ocean","q":"Why do 'zombie worms' drill into the bones of dead whales on the seafloor?"},{"id":"abacus-beads-counting","t":"long-ago","q":"Why can a skilled abacus user calculate faster than someone using a calculator?"},{"id":"akhenaten-one-god","t":"long-ago","q":"Why did one Egyptian pharaoh try to make the whole country worship only a single god?"},{"id":"alexander-the-great-empire","t":"long-ago","q":"Why did a Greek-speaking king end up ruling territory stretching to India?"},{"id":"amphibian-eggs-water","t":"long-ago","q":"Why do amphibians have to lay their eggs in water?"},{"id":"amphibian-fish-tail","t":"long-ago","q":"Why did the earliest land animals still swim more like fish than walk?"},{"id":"amphibian-skin-breathe","t":"long-ago","q":"Why can some amphibians breathe through their own skin?"},{"id":"ancient-boats-rare","t":"long-ago","q":"Why have almost no ancient boats ever been found, even though people used them for ages?"},{"id":"ancient-dna-family-tree","t":"long-ago","q":"Why can a speck of ancient bone reveal an entire family history?"},{"id":"animal-mummies","t":"long-ago","q":"Why did Egyptians mummify millions of animals, not just people?"},{"id":"ankylosaur-club","t":"long-ago","q":"Why did some dinosaurs have a club on their tail?"},{"id":"anna-karenina-principle","t":"long-ago","q":"Why weren't zebras ever domesticated like horses?"},{"id":"archimedes-eureka","t":"long-ago","q":"Why did a Greek thinker run through the streets shouting after stepping into a bathtub?"},{"id":"ard-plough","t":"long-ago","q":"Why did an early plough only scratch the soil instead of turning it over?"},{"id":"armoured-fish","t":"long-ago","q":"Why did some ancient fish wear thick bony armour instead of scales?"},{"id":"arrow-fletching","t":"long-ago","q":"Why do arrows need feathers at the back to fly straight?"},{"id":"arthashastra-chanakya","t":"long-ago","q":"Why does a 2,300-year-old political guidebook still get studied by historians today?"},{"id":"aryabhata-earth-spin","t":"long-ago","q":"Why did an Indian astronomer say the Earth spins, centuries before Europe agreed?"},{"id":"ashoka-edicts-rocks","t":"long-ago","q":"Why did Ashoka carve his messages onto rocks and pillars instead of writing them on paper?"},{"id":"ashoka-kalinga-war","t":"long-ago","q":"Why did a victorious king give up on more war after seeing the battlefield he'd just won?"},{"id":"ashoka-pillar-polish","t":"long-ago","q":"Why do some of Ashoka's 2,200-year-old stone pillars still shine like polished glass?"},{"id":"athens-water-clock-trials","t":"long-ago","q":"Why did Athenian courts use a water clock to time speeches during trials?"},{"id":"augustus-first-citizen","t":"long-ago","q":"Why did Rome's first emperor avoid calling himself a king?"},{"id":"aurochs-extinct","t":"long-ago","q":"Why did the wild ancestor of cattle go extinct while cattle themselves spread worldwide?"},{"id":"ayurveda-origins","t":"long-ago","q":"Why did ancient Indian physicians sort the body into three balancing forces before germs were known?"},{"id":"aztec-allies-conquest","t":"long-ago","q":"Why did thousands of the Aztecs' own neighbours help the Spanish conquer them?"},{"id":"aztec-cacao-money","t":"long-ago","q":"Why did the Aztecs use cacao beans as money?"},{"id":"aztec-disease-toll","t":"long-ago","q":"Why did disease kill more Aztecs than the war with Spain ever did?"},{"id":"aztec-floating-gardens","t":"long-ago","q":"Why did Aztec farmers grow crops on floating islands?"},{"id":"aztec-gods-myth","t":"long-ago","q":"Why do historians doubt the story that Aztecs mistook the Spanish for gods?"},{"id":"aztec-lake-city","t":"long-ago","q":"Why did the Aztecs build their capital in the middle of a lake?"},{"id":"aztec-market-judges","t":"long-ago","q":"Why did the giant Aztec market at Tlatelolco need judges on-site?"},{"id":"aztec-sun-sacrifice","t":"long-ago","q":"Why did the Aztecs believe they had to keep giving blood to the sun?"},{"id":"aztec-tribute-system","t":"long-ago","q":"Why did the Aztec Empire let conquered cities keep their own kings?"},{"id":"baby-skull-soft-spot","t":"long-ago","q":"Why isn't a newborn baby's skull fully joined together?"},{"id":"bark-canoe-building","t":"long-ago","q":"Why could a single sheet of bark, carefully removed, become a whole working canoe?"},{"id":"barley-first-crop","t":"long-ago","q":"Why was barley one of the very first crops ever farmed?"},{"id":"baskets-before-pottery","t":"long-ago","q":"Why did people weave baskets long before they learned to make pottery?"},{"id":"beer-before-bread-myth","t":"long-ago","q":"Why do some historians think early farmers may have been growing grain for beer as much as bread?"},{"id":"bigger-brain-not-smarter","t":"long-ago","q":"Why isn't a bigger brain automatically a cleverer one?"},{"id":"biggest-dinosaur","t":"long-ago","q":"Why was Argentinosaurus so much bigger than any land animal alive today?"},{"id":"birds-are-dinosaurs","t":"long-ago","q":"Why are birds actually dinosaurs?"},{"id":"bitumen-waterproof","t":"long-ago","q":"Why did Mesopotamian builders waterproof their walls with tar dug from the ground?"},{"id":"blade-core-strike","t":"long-ago","q":"Why did skilled toolmakers strike a stone core at one exact spot to peel off long blades?"},{"id":"boab-nut-carving","t":"long-ago","q":"Why did people in the Kimberley carve pictures into a nut instead of on paper or rock?"},{"id":"bogong-moth-gathering","t":"long-ago","q":"Why did thousands of Aboriginal people once travel to the same mountain caves every summer?"},{"id":"bone-needle-evidence","t":"long-ago","q":"Why do ancient bone needles prove people were sewing fitted clothes?"},{"id":"boomerang-many-shapes","t":"long-ago","q":"Why do Aboriginal boomerangs come in so many different shapes?"},{"id":"boomerang-no-return","t":"long-ago","q":"Why do most boomerangs never come back to the thrower?"},{"id":"boomerang-return-flight","t":"long-ago","q":"Why does a returning boomerang curve all the way around in a circle?"},{"id":"boring-billion","t":"long-ago","q":"Why did almost nothing seem to happen for a whole billion years of Earth's history?"},{"id":"bow-stores-energy","t":"long-ago","q":"Why does a bent bow store up energy that shoots an arrow forward?"},{"id":"brain-energy-cost","t":"long-ago","q":"Why does the human brain use such a huge share of the body's energy?"},{"id":"bread-and-circuses","t":"long-ago","q":"Why did Rome give free grain to over a hundred thousand people every month?"},{"id":"brewarrina-fish-traps","t":"long-ago","q":"Why did a river town in New South Wales build a maze of stone walls underwater?"},{"id":"brontosaurus-back","t":"long-ago","q":"Why did Brontosaurus disappear and then come back?"},{"id":"bronze-casting-ritual-vessels","t":"long-ago","q":"Why did ancient Chinese bronze-makers pour molten metal into clay moulds, not stone?"},{"id":"buddhism-siddhartha","t":"long-ago","q":"Why did a wealthy prince give up his palace to sit and think under a tree?"},{"id":"budj-bim-eel-traps","t":"long-ago","q":"Why did people in Victoria dig channels through solid volcanic rock 6,600 years ago?"},{"id":"budj-bim-stone-houses","t":"long-ago","q":"Why does it surprise people that some Aboriginal groups lived in villages of stone houses?"},{"id":"bulla-amulet","t":"long-ago","q":"Why did Roman children wear a special charm around their neck?"},{"id":"bunya-nut-gathering","t":"long-ago","q":"Why did messengers once travel huge distances to invite people to a nut feast?"},{"id":"burial-evidence-of-thought","t":"long-ago","q":"Why is deliberately burying a body seen as a sign of thinking about death?"},{"id":"buried-past","t":"long-ago","q":"Why is old stuff always buried underground?"},{"id":"bush-tucker-signals","t":"long-ago","q":"Why did the flowering of one plant sometimes mean it was time to dig up a completely different one?"},{"id":"buttons-zips","t":"long-ago","q":"Why did clothes have buttons before zips?"},{"id":"cahokia-decline","t":"long-ago","q":"Why did Cahokia empty out long before any Europeans arrived?"},{"id":"cahokia-mounds","t":"long-ago","q":"Why did the people of Cahokia build a mound bigger than the Great Pyramid's base?"},{"id":"cahokia-population","t":"long-ago","q":"Why was Cahokia, in what's now Illinois, once bigger than London?"},{"id":"calendar-365","t":"long-ago","q":"Why is a year 365 days?"},{"id":"calligraphy-brush-pressure","t":"long-ago","q":"Why does Chinese calligraphy use a soft brush instead of a stiff pen?"},{"id":"cambrian-not-explosion","t":"long-ago","q":"Why do scientists call the Cambrian 'explosion' even though it took millions of years?"},{"id":"camel-domestication","t":"long-ago","q":"Why were camels tamed specifically for crossing deserts?"},{"id":"canal-through-city","t":"long-ago","q":"Why do canals running through a city matter as much as canals running to a field?"},{"id":"canoe-scar-trees","t":"long-ago","q":"Why does a curved scar on an old gum tree count as a piece of history?"},{"id":"canopic-jars","t":"long-ago","q":"Why did embalmers store some organs in jars instead of putting them back in the body?"},{"id":"castles","t":"long-ago","q":"Why did castles have such small windows?"},{"id":"cat-self-domesticate","t":"long-ago","q":"Why do many scientists think cats domesticated themselves rather than being tamed by people?"},{"id":"catalhoyuk-no-streets","t":"long-ago","q":"Why didn't Çatalhöyük have any streets at all?"},{"id":"catalhoyuk-roof-door","t":"long-ago","q":"Why did the people of Çatalhöyük climb in through their roofs?"},{"id":"cats-bastet","t":"long-ago","q":"Why did ancient Egyptians treat cats as so special?"},{"id":"cattle-as-currency","t":"long-ago","q":"Why do old words for money often trace back to words for cattle?"},{"id":"cattle-harder-to-tame","t":"long-ago","q":"Why did it take longer to tame wild cattle than to tame goats and sheep?"},{"id":"cave-dwelling-myth","t":"long-ago","q":"Why didn't most ancient humans actually live inside caves?"},{"id":"cave-paintings","t":"long-ago","q":"Why did people paint on cave walls?"},{"id":"cedar-import","t":"long-ago","q":"Why did ancient Egypt import wood from a country far across the sea?"},{"id":"cells-team-up","t":"long-ago","q":"Why do your cells contain tiny structures that used to be their own separate living things?"},{"id":"chandragupta-maurya-empire","t":"long-ago","q":"Why did a young man with no royal blood end up founding India's first huge empire?"},{"id":"chaturanga-chess","t":"long-ago","q":"Why does chess still keep pieces that match an ancient Indian army's four divisions?"},{"id":"chicken-domestication","t":"long-ago","q":"Why was the chicken tamed from a shy jungle bird rather than bred for eggs at first?"},{"id":"childbirth-narrow-hips","t":"long-ago","q":"Why is human childbirth so much harder than it is for chimpanzees?"},{"id":"chinese-writing-thousands-characters","t":"long-ago","q":"Why does Chinese writing use thousands of characters instead of a small alphabet?"},{"id":"chopsticks-bronze-shang","t":"long-ago","q":"Why did people start eating with two sticks instead of a knife and fork?"},{"id":"chuno-freeze-dried-potato","t":"long-ago","q":"Why did people high in the Andes freeze-dry their potatoes?"},{"id":"circus-factions","t":"long-ago","q":"Why did chariot-racing fans in Rome form such fierce rival gangs?"},{"id":"cities-not-egypt","t":"long-ago","q":"Why do so many people think the first cities were built in Egypt?"},{"id":"cities-war-water","t":"long-ago","q":"Why did neighbouring Sumerian cities go to war over water?"},{"id":"city-buried-mound","t":"long-ago","q":"Why do some ancient cities look like ordinary hills from a distance?"},{"id":"city-first-soldiers","t":"long-ago","q":"Why did cities need the world's first full-time soldiers?"},{"id":"city-needs-hinterland","t":"long-ago","q":"Why did a city depend on farmland it couldn't even see from its own walls?"},{"id":"city-needs-market","t":"long-ago","q":"Why did cities need marketplaces once people stopped growing all their own food?"},{"id":"city-not-invented-day","t":"long-ago","q":"Why didn't anyone \"invent\" the city on a particular day?"},{"id":"city-own-king-god","t":"long-ago","q":"Why did every Sumerian city have its own king and its own special god?"},{"id":"city-population-first","t":"long-ago","q":"Why did cities reach populations nobody had ever lived among before?"},{"id":"city-state-meaning","t":"long-ago","q":"Why does \"city-state\" mean something different from a country today?"},{"id":"civil-service-exam","t":"long-ago","q":"Why could a poor farmer's son become a top official in ancient China?"},{"id":"clay-tablet-choice","t":"long-ago","q":"Why did people choose to write on wet clay instead of anything else?"},{"id":"cleopatra-greek","t":"long-ago","q":"Why wasn't Cleopatra actually Egyptian by ancestry?"},{"id":"cliff-drive-hunt","t":"long-ago","q":"Why did some ancient hunters chase whole herds of animals toward a cliff edge?"},{"id":"clothing-cold-climates","t":"long-ago","q":"Why did humans need invented clothing to live in places their bodies alone couldn't handle?"},{"id":"coal-forests","t":"long-ago","q":"Why is so much of the world's coal made from the forests of one ancient period?"},{"id":"colosseum-flooding","t":"long-ago","q":"Why could the Colosseum only stage flooded sea battles in its first years?"},{"id":"colosseum-trapdoors","t":"long-ago","q":"Why could animals and scenery suddenly appear from beneath the Colosseum floor?"},{"id":"compass-feng-shui-first","t":"long-ago","q":"Why was the compass used for fortune-telling before it ever guided a ship?"},{"id":"composite-microliths","t":"long-ago","q":"Why did some ancient tools have dozens of tiny stone blades instead of one big blade?"},{"id":"confucius-not-fortune-cookie","t":"long-ago","q":"Why are most \"Confucius says\" sayings not things he actually said?"},{"id":"cooked-food-energy","t":"long-ago","q":"Why does cooked food give your body more usable energy than the exact same food raw?"},{"id":"cooking-brain-gut","t":"long-ago","q":"Why might cooking be one reason human brains grew so large?"},{"id":"cooking-kills-germs","t":"long-ago","q":"Why does cooking meat make it safer to eat, not just easier to chew?"},{"id":"cooking-smaller-teeth","t":"long-ago","q":"Why did human jaws and teeth get smaller after we started cooking food?"},{"id":"coolamon-carrying-dish","t":"long-ago","q":"Why could one curved wooden dish carry a baby, water and firewood, all in the same day?"},{"id":"corn-domestication","t":"long-ago","q":"Why does corn look nothing like the wild plant it was bred from?"},{"id":"counting-systems-myth","t":"long-ago","q":"Why is it wrong to say Aboriginal languages only had words for 'one', 'two' and 'many'?"},{"id":"crop-rotation-legumes","t":"long-ago","q":"Why did farmers learn to alternate grain crops with beans in the same field?"},{"id":"crossbow-trigger-mechanism","t":"long-ago","q":"Why did the crossbow let an ordinary soldier defeat a trained archer?"},{"id":"cultural-burning","t":"long-ago","q":"Why did Aboriginal peoples burn the bush on purpose?"},{"id":"culture-faster-than-evolution","t":"long-ago","q":"Why did culture let humans adapt to new places faster than evolution could?"},{"id":"cylinder-seal-roll","t":"long-ago","q":"Why did people roll a carved stone cylinder over wet clay?"},{"id":"deadfall-trap","t":"long-ago","q":"Why do some old animal traps use a heavy log balanced to fall by itself?"},{"id":"decimal-place-value","t":"long-ago","q":"Why does writing a number like 205 work so much better than older numeral systems?"},{"id":"demic-diffusion-farmers-migrated","t":"long-ago","q":"Why does ancient DNA show farming spread across Europe by actual farmers migrating, not just neighbours copying an idea?"},{"id":"denisovan-finger-bone","t":"long-ago","q":"Why do we know a whole ancient human group mainly from one finger bone?"},{"id":"denisovan-no-face","t":"long-ago","q":"Why don't we actually know what a Denisovan's face looked like?"},{"id":"denisovan-tibet-gene","t":"long-ago","q":"Why can people in Tibet breathe easily at heights that leave others gasping?"},{"id":"dholavira-water","t":"long-ago","q":"Why did the desert city of Dholavira dig giant stepped tanks around itself?"},{"id":"didgeridoo-origin-region","t":"long-ago","q":"Why wasn't the didgeridoo traditionally played across the whole of Aboriginal Australia?"},{"id":"die-young","t":"long-ago","q":"Why did people die so young long ago?"},{"id":"dilly-bags-fibre-string","t":"long-ago","q":"Why did twisting plant fibre together matter as much as any tool made of stone?"},{"id":"dimetrodon-sail","t":"long-ago","q":"Why did Dimetrodon carry a giant sail on its back?"},{"id":"dino-bird-survive","t":"long-ago","q":"Why did birds survive the disaster that wiped out other dinosaurs?"},{"id":"dino-colour","t":"long-ago","q":"Why do we know what colour dinosaurs were?"},{"id":"dino-crests","t":"long-ago","q":"Why did some dinosaurs have big crests on their heads?"},{"id":"dino-diet-teeth","t":"long-ago","q":"Why can scientists tell what a dinosaur ate from its teeth?"},{"id":"dino-digging","t":"long-ago","q":"Why does digging up a dinosaur take so long?"},{"id":"dino-eggs","t":"long-ago","q":"Why did dinosaurs lay eggs instead of having live babies?"},{"id":"dino-feathers","t":"long-ago","q":"Why did some dinosaurs have feathers?"},{"id":"dino-footprints","t":"long-ago","q":"Why do dinosaur footprints survive millions of years?"},{"id":"dino-fossil-rare","t":"long-ago","q":"Why are dinosaur fossils so rare?"},{"id":"dino-growth-rings","t":"long-ago","q":"Why can scientists tell a dinosaur's age from its bones?"},{"id":"dino-legs-under","t":"long-ago","q":"Why did dinosaurs stand up straight instead of sprawling like lizards?"},{"id":"dino-mistakes","t":"long-ago","q":"Why did scientists once put a dinosaur's thumb on its nose?"},{"id":"dino-names","t":"long-ago","q":"Why do dinosaurs have such long names?"},{"id":"dino-nests","t":"long-ago","q":"Why did some dinosaurs build nests together?"},{"id":"dino-poo","t":"long-ago","q":"Why do scientists study fossilised dinosaur poo?"},{"id":"dino-reign-length","t":"long-ago","q":"Why did dinosaurs rule the Earth for so long?"},{"id":"dino-skin-look","t":"long-ago","q":"Why do we now think many dinosaurs looked different from old pictures?"},{"id":"dino-sounds","t":"long-ago","q":"Why don't we know what dinosaurs sounded like?"},{"id":"dino-speed","t":"long-ago","q":"Why could some dinosaurs run so fast?"},{"id":"dino-teeth-replace","t":"long-ago","q":"Why did dinosaurs never run out of teeth?"},{"id":"dino-warm-blood","t":"long-ago","q":"Why do scientists think some dinosaurs were warm-blooded?"},{"id":"dinosaurs-big","t":"long-ago","q":"Why were dinosaurs so big?"},{"id":"dinosaurs-gone","t":"long-ago","q":"Why did the dinosaurs die out?"},{"id":"division-of-labour-hunt","t":"long-ago","q":"Why did hunting-and-gathering groups usually split jobs between people?"},{"id":"dna-code","t":"long-ago","q":"Why do all living things use the same genetic code?"},{"id":"dog-before-farming","t":"long-ago","q":"Why was the dog already tame thousands of years before the first farm existed?"},{"id":"domestication-selective-breeding","t":"long-ago","q":"Why did picking the 'best' seeds or animals each year slowly reshape a whole species?"},{"id":"domestication-syndrome","t":"long-ago","q":"Why do so many different tame animals end up with floppy ears and patchy coats?"},{"id":"donkey-domestication","t":"long-ago","q":"Why was the donkey tamed to carry loads before the horse was ridden?"},{"id":"dragon-boat-festival-origin","t":"long-ago","q":"Why do dragon boat races remember a poet who drowned himself in protest?"},{"id":"dragon-symbol-emperor","t":"long-ago","q":"Why did the dragon become the symbol of the Chinese emperor?"},{"id":"dry-cave-preserves","t":"long-ago","q":"Why do dry caves preserve ancient tools that a wet, open field destroys within years?"},{"id":"ediacaran-flat","t":"long-ago","q":"Why were the first big living things flat and thin instead of having a round body?"},{"id":"ediacaran-strange","t":"long-ago","q":"Why do the oldest large fossils on Earth look like nothing alive today?"},{"id":"edwin-smith-papyrus","t":"long-ago","q":"Why did an ancient Egyptian doctor write down step-by-step surgery instructions on papyrus?"},{"id":"egyptian-beer","t":"long-ago","q":"Why did so many ancient Egyptians drink beer every day, including children?"},{"id":"egyptian-calendar","t":"long-ago","q":"Why does the ancient Egyptian calendar still echo through the year we use today?"},{"id":"egyptian-wigs","t":"long-ago","q":"Why did Egyptian men and women often shave their heads and wear wigs?"},{"id":"empires-fall","t":"long-ago","q":"Why do empires fall apart?"},{"id":"emu-in-the-sky","t":"long-ago","q":"Why does a huge emu shape in the night sky have no stars in it at all?"},{"id":"epic-real-king","t":"long-ago","q":"Why is the world's oldest surviving long story about a real king of a real city?"},{"id":"epidemic-disease-density","t":"long-ago","q":"Why did diseases like measles need farming-sized crowds of people to survive at all?"},{"id":"eunuchs-imperial-court","t":"long-ago","q":"Why did some of the most powerful palace figures serve as eunuchs?"},{"id":"evolution-not-ladder","t":"long-ago","q":"Why is it wrong to picture evolution as a straight line of apes becoming humans?"},{"id":"explorers","t":"long-ago","q":"Why did explorers sail off into oceans nobody had mapped?"},{"id":"eye-of-horus","t":"long-ago","q":"Why did Egyptians wear an eye-shaped charm called the Eye of Horus?"},{"id":"fake-beards","t":"long-ago","q":"Why did Egyptian pharaohs wear fake beards, even the female ones?"},{"id":"fake-cat-mummies","t":"long-ago","q":"Why are so many ancient Egyptian cat mummies not actually cats?"},{"id":"fallow-fields","t":"long-ago","q":"Why did some fields need a year of doing nothing at all?"},{"id":"false-doors","t":"long-ago","q":"Why did Egyptians carve doors into tomb walls that couldn't actually be opened?"},{"id":"farming-population-growth","t":"long-ago","q":"Why did farming let population grow faster despite farmers often being less healthy?"},{"id":"farming-start","t":"long-ago","q":"Why did people start farming?"},{"id":"feral-animals-reverting","t":"long-ago","q":"Why do escaped farm animals sometimes go wild again within a few generations?"},{"id":"fertile-crescent-climate","t":"long-ago","q":"Why did farming begin in the Fertile Crescent rather than somewhere else nearby?"},{"id":"few-things-left","t":"long-ago","q":"Why is there so little left from long ago?"},{"id":"fire","t":"long-ago","q":"Why was fire so important to humans?"},{"id":"fire-bow-drill","t":"long-ago","q":"Why did wrapping a cord around the stick make fire easier to start?"},{"id":"fire-carried-embers","t":"long-ago","q":"Why did ancient people carry fire with them instead of lighting a new one each time?"},{"id":"fire-drill-technique","t":"long-ago","q":"Why does spinning a stick fast enough between your palms eventually make it burst into flame?"},{"id":"fire-flint-spark","t":"long-ago","q":"Why do sparks fly when you strike flint against a lump of iron pyrite?"},{"id":"fire-friction","t":"long-ago","q":"Why does rubbing two sticks together eventually make fire?"},{"id":"first-boats-log","t":"long-ago","q":"Why do scientists think the very first boats were simply hollowed-out logs?"},{"id":"first-bone-needles","t":"long-ago","q":"Why were the first sewing needles carved from bone instead of anything else?"},{"id":"first-cities","t":"long-ago","q":"Why did people start living in cities?"},{"id":"first-forests-cooled-earth","t":"long-ago","q":"Why did the arrival of the first forests cool down the whole planet?"},{"id":"fish-fins-legs","t":"long-ago","q":"Why do some ancient fish fossils have fins that look almost like legs?"},{"id":"fish-out-water","t":"long-ago","q":"Why can't a fish out of water breathe, even though there's plenty of oxygen in the air?"},{"id":"fish-smoking-preservation","t":"long-ago","q":"Why did hanging fish over a smoky fire keep it edible for weeks?"},{"id":"fitted-clothes-warmth","t":"long-ago","q":"Why did closely fitted clothing matter so much for surviving an ice age?"},{"id":"flat-earth","t":"long-ago","q":"Why did people think the Earth was flat?"},{"id":"flint-fracture","t":"long-ago","q":"Why does flint break into smooth curved flakes instead of jagged lumps?"},{"id":"flood-story-before-noah","t":"long-ago","q":"Why does a Mesopotamian flood story sound so much like Noah's ark?"},{"id":"floods-shaped-cities","t":"long-ago","q":"Why did unpredictable floods shape where Mesopotamia's first cities could be built?"},{"id":"fluted-spear-point","t":"long-ago","q":"Why did some ancient North American hunters carve a groove into the base of a spear point?"},{"id":"founder-crops-fertile-crescent","t":"long-ago","q":"Why do archaeologists call eight particular plants the 'founder crops'?"},{"id":"gargi-maitreyi-scholars","t":"long-ago","q":"Why do a couple of women's names keep appearing as sharp debaters in texts from an era when writing was rare?"},{"id":"gastroliths","t":"long-ago","q":"Why did some dinosaurs swallow stones?"},{"id":"gathering-most-calories","t":"long-ago","q":"Why did gathered plants often feed a group better than hunted meat did?"},{"id":"gesture-before-speech","t":"long-ago","q":"Why do many scientists think pointing and gesturing came before spoken words?"},{"id":"ghost-population-dna","t":"long-ago","q":"Why do some people's DNA hint at a human relative nobody has ever found a fossil of?"},{"id":"giant-dragonfly","t":"long-ago","q":"Why was one ancient dragonfly as big as a seagull?"},{"id":"gift-of-nile","t":"long-ago","q":"Why is Egypt sometimes called \"the gift of the Nile\"?"},{"id":"gladiator-survival","t":"long-ago","q":"Why didn't most gladiator fights end in death?"},{"id":"gladius-short-sword","t":"long-ago","q":"Why did Rome's legions fight with a short sword instead of a long one?"},{"id":"goat-sheep-first","t":"long-ago","q":"Why were goats and sheep among the very first animals ever tamed?"},{"id":"grain-storage-dry","t":"long-ago","q":"Why can dry grain last for years when almost every other food rots within days?"},{"id":"granaries-surplus-storage","t":"long-ago","q":"Why did farming villages need to build the world's first proper storehouses?"},{"id":"grand-canal-engineering","t":"long-ago","q":"Why did ancient Chinese engineers dig a canal over a thousand kilometres long?"},{"id":"grandmother-hypothesis","t":"long-ago","q":"Why might grandmothers help explain why humans live so long past having babies?"},{"id":"great-wall","t":"long-ago","q":"Why did China build the Great Wall?"},{"id":"great-wall-forced-labourers","t":"long-ago","q":"Why did so many workers die building the Great Wall?"},{"id":"great-wall-length-survey","t":"long-ago","q":"Why did it take surveyors six years to measure the Great Wall's true length?"},{"id":"great-wall-many-dynasties","t":"long-ago","q":"Why isn't the Great Wall actually one single wall built all at once?"},{"id":"great-wall-not-visible-space","t":"long-ago","q":"Why can't the Great Wall of China actually be seen from space?"},{"id":"great-wall-sticky-rice-mortar","t":"long-ago","q":"Why did Ming dynasty builders mix sticky rice into the Great Wall's mortar?"},{"id":"great-wall-watchtowers-smoke","t":"long-ago","q":"Why did Great Wall watchtowers send messages using smoke and fire?"},{"id":"greek-agora-marketplace","t":"long-ago","q":"Why was the agora the busiest place in an ancient Greek city?"},{"id":"greek-alphabet-phoenician","t":"long-ago","q":"Why did the Greeks add vowels to an alphabet they borrowed from someone else?"},{"id":"greek-city-states-independent","t":"long-ago","q":"Why wasn't ancient Greece actually one single country?"},{"id":"greek-coins-invention","t":"long-ago","q":"Why did Greek city-states each mint their own separate coins?"},{"id":"greek-colonies-mediterranean","t":"long-ago","q":"Why did Greek cities end up scattered around the Mediterranean and Black Sea?"},{"id":"greek-democracy-lottery","t":"long-ago","q":"Why did Athens choose many officials by random lottery instead of voting for them?"},{"id":"greek-democracy-not-everyone","t":"long-ago","q":"Why didn't ancient Greek democracy let everyone vote?"},{"id":"greek-earthquakes-poseidon","t":"long-ago","q":"Why did ancient Greeks link earthquakes to the god of the sea?"},{"id":"greek-education-boys","t":"long-ago","q":"Why did most Greek schooling outside Sparta focus on music and poetry, not fighting?"},{"id":"greek-farming-terraces","t":"long-ago","q":"Why did Greek farmers carve steps into hillsides instead of farming flat land?"},{"id":"greek-funeral-customs","t":"long-ago","q":"Why did ancient Greeks place a coin in the mouth of their dead before burial?"},{"id":"greek-gods-explain-world","t":"long-ago","q":"Why did ancient Greeks tell stories about gods causing everyday events?"},{"id":"greek-herodotus-history","t":"long-ago","q":"Why is one ancient Greek writer often called \"the father of history\"?"},{"id":"greek-hospitality-xenia","t":"long-ago","q":"Why did ancient Greeks treat welcoming a stranger into their home as a sacred duty?"},{"id":"greek-libraries-scrolls","t":"long-ago","q":"Why did a Greek-founded library in Egypt try to collect every book in the known world?"},{"id":"greek-lighthouse-alexandria","t":"long-ago","q":"Why did Greek engineers build one of the tallest ancient structures just to guide ships into one harbour?"},{"id":"greek-mathematics-proof","t":"long-ago","q":"Why did Greek mathematicians insist on proving ideas rather than just testing them?"},{"id":"greek-medicine-hippocrates","t":"long-ago","q":"Why is a Greek doctor from 2,400 years ago still linked to modern medicine?"},{"id":"greek-olive-oil-uses","t":"long-ago","q":"Why was olive oil used for so much more than cooking in ancient Greece?"},{"id":"greek-oracle-delphi","t":"long-ago","q":"Why did powerful kings travel far just to hear one priestess speak in riddles?"},{"id":"greek-ostracism","t":"long-ago","q":"Why could Athenians vote to send someone away for ten years with no trial?"},{"id":"greek-persian-wars","t":"long-ago","q":"Why did small Greek city-states manage to defeat the vast Persian Empire?"},{"id":"greek-phalanx-formation","t":"long-ago","q":"Why did Greek soldiers fight standing in a tight wall of shields?"},{"id":"greek-philosophy-not-religion","t":"long-ago","q":"Why did some Greek thinkers try to explain nature without blaming the gods?"},{"id":"greek-plague-athens","t":"long-ago","q":"Why did a mysterious disease outbreak help weaken Athens during its war with Sparta?"},{"id":"greek-pottery-figures","t":"long-ago","q":"Why do historians learn so much about daily Greek life from painted pots?"},{"id":"greek-slavery-economy","t":"long-ago","q":"Why did slavery sit at the centre of everyday life in ancient Greek cities?"},{"id":"greek-sport-events","t":"long-ago","q":"Why did chariot racing count as an Olympic event even though the driver didn't win the prize?"},{"id":"greek-statues-painted","t":"long-ago","q":"Why were ancient Greek statues actually brightly painted, not plain white?"},{"id":"greek-symposium-drinking","t":"long-ago","q":"Why did wealthy Greek men host parties built around watered-down wine?"},{"id":"greek-theatre-masks","t":"long-ago","q":"Why did ancient Greek actors perform wearing large painted masks?"},{"id":"greek-tragedy-comedy","t":"long-ago","q":"Why did ancient Greek plays split so clearly into tragedy and comedy?"},{"id":"greek-trireme-oars","t":"long-ago","q":"Why did Greek warships need up to 170 rowers just to move?"},{"id":"greek-women-restricted","t":"long-ago","q":"Why did most women in ancient Athens rarely leave their own homes?"},{"id":"greek-writing-lost-recovered","t":"long-ago","q":"Why did an early form of Greek writing disappear for centuries before anyone could read it?"},{"id":"grid-city-vs-tangle","t":"long-ago","q":"Why did one ancient city lay its streets out in a grid while another grew every which way?"},{"id":"ground-ochre-sun-protection","t":"long-ago","q":"Why did rubbing ochre onto skin do more than just decorate it?"},{"id":"group-hunt-big-prey","t":"long-ago","q":"Why could a small group of hunters bring down an animal ten times their own size?"},{"id":"guinea-pig-food","t":"long-ago","q":"Why did Andean people keep guinea pigs inside their homes?"},{"id":"gunpowder-accident-immortality","t":"long-ago","q":"Why did an accident while hunting for eternal life create gunpowder?"},{"id":"gunpowder-fire-lance-weapon","t":"long-ago","q":"Why was a bamboo tube tied to a spear one of the first gunpowder weapons?"},{"id":"gunpowder-rockets-early","t":"long-ago","q":"Why did Chinese soldiers strap gunpowder tubes to arrows?"},{"id":"gunyah-shelter-construction","t":"long-ago","q":"Why could a shelter built from bark and branches go up in under an hour but still keep out rain?"},{"id":"gupta-golden-age","t":"long-ago","q":"Why do historians often call the Gupta period a \"golden age\" for ancient India?"},{"id":"gurukul-education","t":"long-ago","q":"Why did ancient Indian students often live with their teacher's family for years?"},{"id":"hafting-stone-point","t":"long-ago","q":"Why did a stone spear point need to be glued as well as tied onto its shaft?"},{"id":"hammurabi-borrowed-laws","t":"long-ago","q":"Why did Hammurabi's famous laws borrow from ideas centuries older?"},{"id":"hand-stencil-technique","t":"long-ago","q":"Why do so many rock art sites have a hand shape but no handprint?"},{"id":"handaxe-symmetry","t":"long-ago","q":"Why is a stone hand axe shaped the same on both sides, like a teardrop?"},{"id":"hapi-flood-god","t":"long-ago","q":"Why did Egyptians picture their flood god with a man's face but a rounded, fuller body?"},{"id":"harappan-mesopotamia-seals","t":"long-ago","q":"Why do seals carved in the Indus Valley turn up in ancient Mesopotamian cities?"},{"id":"hatshepsut-beard","t":"long-ago","q":"Why do statues of the female pharaoh Hatshepsut show her wearing a fake beard?"},{"id":"heat-treated-stone","t":"long-ago","q":"Why did some ancient toolmakers heat stone in a fire before knapping it?"},{"id":"helpless-human-babies","t":"long-ago","q":"Why are human babies born so much less developed than other primate babies?"},{"id":"hieratic-script","t":"long-ago","q":"Why did Egyptians invent a second, faster kind of writing alongside hieroglyphs?"},{"id":"hieroglyphs-lost","t":"long-ago","q":"Why could nobody read hieroglyphs for over a thousand years?"},{"id":"hieroglyphs-not-pictures","t":"long-ago","q":"Why did ancient Egyptians write in hieroglyphs instead of a simple alphabet?"},{"id":"hinduism-not-founded","t":"long-ago","q":"Why doesn't Hinduism have one founder or one holy book, the way some other religions do?"},{"id":"horse-domestication-steppe","t":"long-ago","q":"Why were horses tamed thousands of years after cattle and sheep?"},{"id":"horses-everything","t":"long-ago","q":"Why did people use horses for everything?"},{"id":"humans-every-climate","t":"long-ago","q":"Why can humans survive in nearly every climate on Earth, unlike most mammals?"},{"id":"hypocaust-heating","t":"long-ago","q":"Why did wealthy Romans heat their floors from underneath?"},{"id":"ice-age","t":"long-ago","q":"Why were there ice ages?"},{"id":"imhotep","t":"long-ago","q":"Why is Imhotep remembered as one of history's first named engineers?"},{"id":"inca-chasqui-relay","t":"long-ago","q":"Why did Inca messengers run in relay teams instead of one runner going the whole way?"},{"id":"inca-civil-war-conquest","t":"long-ago","q":"Why was the Inca Empire fighting a civil war right when Pizarro arrived?"},{"id":"inca-mummy-rulers","t":"long-ago","q":"Why did the Inca keep treating dead emperors as if they still owned property?"},{"id":"inca-quipu-mystery","t":"long-ago","q":"Why can't modern experts fully read quipu knots today?"},{"id":"inca-quipu-records","t":"long-ago","q":"Why did the Inca keep records by tying knots in string?"},{"id":"inca-roads-no-wheel","t":"long-ago","q":"Why did the Inca build thousands of kilometres of roads without using wheels?"},{"id":"inca-rope-bridges","t":"long-ago","q":"Why did the Inca build bridges out of woven grass rope?"},{"id":"inca-stone-fitting","t":"long-ago","q":"Why do Inca stone walls fit together so tightly without mortar?"},{"id":"inca-storehouses","t":"long-ago","q":"Why did the Inca build thousands of storehouses along their roads?"},{"id":"inca-terraces","t":"long-ago","q":"Why did the Inca carve their mountainsides into staircases of terraces?"},{"id":"inca-wheel-toys","t":"long-ago","q":"Why did the Inca know about wheels but never use them for transport?"},{"id":"indus-cotton","t":"long-ago","q":"Why was the Indus Valley one of the earliest places in the world to grow and weave cotton?"},{"id":"indus-decline-rivers","t":"long-ago","q":"Why did the mighty Indus Valley cities empty out over just a few centuries?"},{"id":"indus-great-bath","t":"long-ago","q":"Why did Mohenjo-daro build a giant waterproof pool with no religious carvings to explain it?"},{"id":"indus-no-palaces","t":"long-ago","q":"Why haven't archaeologists found a grand palace or royal tomb in the Indus Valley cities?"},{"id":"indus-script-unread","t":"long-ago","q":"Why can't anyone read the Indus Valley's own writing?"},{"id":"indus-seals-unicorn","t":"long-ago","q":"Why does one mysterious horned animal appear on more Indus Valley seals than any other?"},{"id":"indus-standard-bricks","t":"long-ago","q":"Why do bricks from Indus Valley cities hundreds of kilometres apart all share the same shape?"},{"id":"indus-valley-drainage","t":"long-ago","q":"Why did Indus Valley cities build covered drains under almost every street?"},{"id":"indus-weights-cubes","t":"long-ago","q":"Why do tiny stone cubes found across the Indus Valley all follow the same doubling pattern?"},{"id":"industrial-revolution","t":"long-ago","q":"Why did factories change the world?"},{"id":"insect-breathing","t":"long-ago","q":"Why do insects breathe through holes in the side of their body instead of a nose?"},{"id":"insulae-fire-risk","t":"long-ago","q":"Why were Rome's apartment blocks so likely to catch fire and collapse?"},{"id":"insulae-no-kitchen","t":"long-ago","q":"Why didn't poor Romans in the city cook their own dinner at home?"},{"id":"iron-pillar-delhi","t":"long-ago","q":"Why has a 1,600-year-old iron pillar in Delhi barely rusted?"},{"id":"iroquois-confederacy","t":"long-ago","q":"Why did the Haudenosaunee build a system for removing bad leaders?"},{"id":"irrigation-canals-mesopotamia","t":"long-ago","q":"Why did farmers in Mesopotamia dig canals far from the river itself?"},{"id":"jade-more-valuable-gold","t":"long-ago","q":"Why did ancient Chinese people often value jade more highly than gold?"},{"id":"jainism-ahimsa","t":"long-ago","q":"Why do some Jain monks sweep the ground gently in front of their own feet as they walk?"},{"id":"jawless-fish","t":"long-ago","q":"Why didn't the first fish have jaws?"},{"id":"jericho-wall-first","t":"long-ago","q":"Why were the walls of Jericho built thousands of years before any real city existed?"},{"id":"julian-calendar-fix","t":"long-ago","q":"Why did Julius Caesar have to add extra days to fix the calendar?"},{"id":"king-rule-from-gods","t":"long-ago","q":"Why did some Sumerian kings say the gods themselves gave them the right to rule?"},{"id":"kite-military-signal","t":"long-ago","q":"Why were the very first kites built for signalling rather than for fun?"},{"id":"knapping-takes-years","t":"long-ago","q":"Why does learning to knap a stone tool properly take years of practice?"},{"id":"knight-armour","t":"long-ago","q":"Why did knights wear metal armour?"},{"id":"kohl-eyeliner","t":"long-ago","q":"Why did ancient Egyptians paint thick black lines around their eyes?"},{"id":"lactase-persistence","t":"long-ago","q":"Why can some adults digest milk while others can't, and what does farming have to do with it?"},{"id":"lady-dai-mummy","t":"long-ago","q":"Why is a two-thousand-year-old Chinese noblewoman's body still eerily well preserved?"},{"id":"land-bridge-tasmania","t":"long-ago","q":"Why were Tasmanian Aboriginal people cut off from mainland Australia for thousands of years?"},{"id":"larynx-position-speech","t":"long-ago","q":"Why does where an animal's voice box sits affect whether it could ever speak?"},{"id":"lead-pipes-myth","t":"long-ago","q":"Why weren't Romans as poisoned by their lead pipes as people often say?"},{"id":"legion-eagle-standard","t":"long-ago","q":"Why was losing a legion's eagle treated as a catastrophe?"},{"id":"lentils-nitrogen","t":"long-ago","q":"Why did early farmers usually grow beans and lentils alongside their grain?"},{"id":"lice-clothing-clock","t":"long-ago","q":"Why can lice DNA reveal roughly when humans started wearing clothes?"},{"id":"life-after-snowball","t":"long-ago","q":"Why did life get much more complicated soon after Earth thawed from its deep freeze?"},{"id":"life-first-water","t":"long-ago","q":"Why did life first appear in water, not on land?"},{"id":"life-vents","t":"long-ago","q":"Why do many scientists think life began at underwater volcanic vents?"},{"id":"linen-clothing","t":"long-ago","q":"Why did ancient Egyptians wear light linen instead of warm wool?"},{"id":"lion-capital-emblem","t":"long-ago","q":"Why did a stone carving from over 2,000 years ago end up on India's currency and government seal?"},{"id":"lion-man-figurine","t":"long-ago","q":"Why is a tiny ivory figure of a lion-man considered one of the oldest artworks in the world?"},{"id":"llama-alpaca-andes","t":"long-ago","q":"Why did Andean farmers tame llamas and alpacas instead of cattle?"},{"id":"long-human-childhood","t":"long-ago","q":"Why do human children take so much longer to grow up than chimpanzees?"},{"id":"longhouse-design","t":"long-ago","q":"Why did some Native American nations build one long house for many families?"},{"id":"lothal-dock","t":"long-ago","q":"Why did archaeologists call a large brick basin at Lothal the world's earliest known dock?"},{"id":"maize-teosinte","t":"long-ago","q":"Why did corn's wild ancestor look nothing like corn?"},{"id":"mandate-of-heaven","t":"long-ago","q":"Why did ancient Chinese emperors claim the sky itself had chosen them to rule?"},{"id":"many-human-species-once","t":"long-ago","q":"Why did several different kinds of humans once share the Earth?"},{"id":"map-monsters","t":"long-ago","q":"Why did old maps have monsters on them?"},{"id":"mauryan-spies-bureaucracy","t":"long-ago","q":"Why did the Mauryan empire employ secret officials whose job was watching other officials?"},{"id":"maya-2012-myth","t":"long-ago","q":"Why did people think the Maya calendar predicted the world would end in 2012?"},{"id":"maya-ballcourt-slopes","t":"long-ago","q":"Why do Maya ball courts have slanted side walls?"},{"id":"maya-cities-emptied","t":"long-ago","q":"Why did big Maya cities empty out centuries before Europeans arrived?"},{"id":"maya-glyphs-decoded","t":"long-ago","q":"Why did it take scholars over a century to read Maya writing?"},{"id":"maya-long-count-base20","t":"long-ago","q":"Why does the ancient Maya calendar count in twenties instead of tens?"},{"id":"maya-reservoirs","t":"long-ago","q":"Why did Maya cities have to build their own giant reservoirs?"},{"id":"maya-stepped-pyramids","t":"long-ago","q":"Why are Maya pyramids built as stacked steps instead of smooth sides?"},{"id":"maya-two-calendars","t":"long-ago","q":"Why did the Maya run two different calendars side by side?"},{"id":"maya-venus-cycle","t":"long-ago","q":"Why did Maya priests track the planet Venus so precisely they timed wars by it?"},{"id":"mesoamerican-ballgame-hips","t":"long-ago","q":"Why did players in the Mesoamerican ballgame hit the ball with their hips?"},{"id":"mesopotamia-no-stone","t":"long-ago","q":"Why did Mesopotamian cities have almost no stone or timber to build with?"},{"id":"message-sticks","t":"long-ago","q":"Why did a carved stick sometimes travel hundreds of kilometres before anyone spoke a word?"},{"id":"migration-waves","t":"long-ago","q":"Why did early humans leave Africa in several waves, not just one journey?"},{"id":"mississippian-trade-network","t":"long-ago","q":"Why did ancient traders move copper and seashells thousands of kilometres without wheels or horses?"},{"id":"mitochondrial-eve-myth","t":"long-ago","q":"Why wasn't 'Mitochondrial Eve' actually the first woman?"},{"id":"moche-portrait-pots","t":"long-ago","q":"Why did Moche potters shape jars to look like real human faces?"},{"id":"mohenjo-daro-drains","t":"long-ago","q":"Why did Mohenjo-daro have drains running under almost every street?"},{"id":"moon-tide-shellfish","t":"long-ago","q":"Why did knowing the Moon's shape matter as much as knowing the tide times?"},{"id":"movable-type-bi-sheng-clay","t":"long-ago","q":"Why didn't movable type replace woodblock printing in China?"},{"id":"mudbrick-vs-stone","t":"long-ago","q":"Why did Egyptians build ordinary houses from mud brick but temples from stone?"},{"id":"multiple-independent-origins-farming","t":"long-ago","q":"Why did farming spring up independently in several parts of the world at roughly the same time?"},{"id":"mummies","t":"long-ago","q":"Why did the Egyptians make mummies?"},{"id":"murujuga-rock-engravings","t":"long-ago","q":"Why does one stretch of Western Australian coast hold more rock art than almost anywhere else on Earth?"},{"id":"museums","t":"long-ago","q":"Why do we have museums?"},{"id":"nalanda-university","t":"long-ago","q":"Why did students travel thousands of kilometres to study at one ancient Indian university?"},{"id":"natufian-settling-before-farming","t":"long-ago","q":"Why did some people build permanent villages before they ever grew a crop?"},{"id":"nazca-lines","t":"long-ago","q":"Why did the Nazca carve lines into the desert only clearly visible from way up high?"},{"id":"neanderthal-afterlife-debate","t":"long-ago","q":"Why do scientists still argue over what Neanderthal burials really mean?"},{"id":"neanderthal-build","t":"long-ago","q":"Why were Neanderthal bodies built so much stockier than ours?"},{"id":"neanderthal-burial","t":"long-ago","q":"Why do scientists think Neanderthals buried their dead on purpose?"},{"id":"neanderthal-dna-in-us","t":"long-ago","q":"Why do most people alive today carry a little bit of Neanderthal DNA?"},{"id":"neanderthal-immune-genes","t":"long-ago","q":"Why did Neanderthal DNA help ancient humans survive new diseases outside Africa?"},{"id":"neanderthal-nose","t":"long-ago","q":"Why did Neanderthals have such big, wide noses?"},{"id":"needle-eye","t":"long-ago","q":"Why do sewing needles need a hole at one end instead of just a hook?"},{"id":"nero-fiddle-myth","t":"long-ago","q":"Why couldn't Nero have really fiddled while Rome burned?"},{"id":"net-hunting","t":"long-ago","q":"Why did woven nets let hunters catch many animals at once instead of just one?"},{"id":"nile-flood-cause","t":"long-ago","q":"Why did the Nile flood every single year, when most rivers don't?"},{"id":"nile-flood-clockwork","t":"long-ago","q":"Why could Egyptian farmers count on the Nile flooding almost on schedule every year?"},{"id":"nippur-clay-map","t":"long-ago","q":"Why did people draw one of the world's oldest city maps on a piece of clay?"},{"id":"no-biological-races","t":"long-ago","q":"Why don't scientists divide humans into separate biological races?"},{"id":"no-camels","t":"long-ago","q":"Why don't real ancient Egyptian tomb paintings show camels, even though modern pictures of Egypt often include them?"},{"id":"no-cavemen-dinosaurs","t":"long-ago","q":"Why did cavemen and dinosaurs never actually meet?"},{"id":"no-coins-first-cities","t":"long-ago","q":"Why weren't there any coins in the world's first cities?"},{"id":"no-fossil-for-language","t":"long-ago","q":"Why can't scientists dig up a fossil of the first spoken word?"},{"id":"obelisks","t":"long-ago","q":"Why did pharaohs raise tall, pointed stone needles called obelisks?"},{"id":"obsidian-edge","t":"long-ago","q":"Why can a flake of obsidian be sharper than a surgeon's steel blade?"},{"id":"ochre-before-cave-art","t":"long-ago","q":"Why were people using coloured pigment long before the first cave paintings?"},{"id":"ochre-in-graves","t":"long-ago","q":"Why does red powder sprinkled in an ancient grave excite archaeologists?"},{"id":"ochre-trade-network","t":"long-ago","q":"Why did red and yellow rock sometimes travel over a thousand kilometres from where it was dug?"},{"id":"oldest-culture","t":"long-ago","q":"Why is Aboriginal Australia called the oldest living culture on Earth?"},{"id":"oldest-law-not-hammurabi","t":"long-ago","q":"Why do we credit a Sumerian king, not Hammurabi, with the oldest known law code?"},{"id":"oldest-shell-beads","t":"long-ago","q":"Why do 100,000-year-old pierced shells count as some of the first jewellery?"},{"id":"olmec-language-unknown","t":"long-ago","q":"Why don't we know for certain what language the Olmec people spoke?"},{"id":"olmec-mother-culture","t":"long-ago","q":"Why do later Mesoamerican cultures share symbols that first appear with the Olmec?"},{"id":"olmec-stone-heads","t":"long-ago","q":"Why did the Olmec drag stones as heavy as a bus to carve giant heads?"},{"id":"olympics-nude-athletes","t":"long-ago","q":"Why did ancient Greek athletes compete completely naked?"},{"id":"olympics-truce","t":"long-ago","q":"Why did wars sometimes stop for the ancient Olympic Games?"},{"id":"oracle-bones-dragon-medicine","t":"long-ago","q":"Why were ancient Chinese oracle bones once sold in shops as medicine?"},{"id":"oracle-bones-turtle-shell-crack","t":"long-ago","q":"Why did Shang priests crack turtle shells to ask about the future?"},{"id":"oral-tradition-volcano","t":"long-ago","q":"Why do some Aboriginal stories seem to describe a volcano erupting tens of thousands of years ago?"},{"id":"ordinary-life-unknown","t":"long-ago","q":"Why do we know so little about ordinary families in the first cities?"},{"id":"out-of-africa-evidence","t":"long-ago","q":"Why do scientists think everyone alive today has African ancestors?"},{"id":"oxygen-waste","t":"long-ago","q":"Why is the oxygen you breathe actually a leftover from splitting water?"},{"id":"ozone-shield","t":"long-ago","q":"Why couldn't life survive on land until an invisible shield formed in the sky?"},{"id":"paid-in-barley-beer","t":"long-ago","q":"Why were early city workers paid in barley and beer instead of money?"},{"id":"panchatantra-fables","t":"long-ago","q":"Why did ancient Indian storytellers teach lessons through talking animals instead of direct advice?"},{"id":"paper-cai-lun-standardise","t":"long-ago","q":"Why is Cai Lun given credit for inventing paper when paper existed before him?"},{"id":"papyrus-invention","t":"long-ago","q":"Why was papyrus such a big deal for the ancient world?"},{"id":"patron-client-system","t":"long-ago","q":"Why did poorer Romans line up outside a rich man's house every morning?"},{"id":"permian-great-dying","t":"long-ago","q":"Why is one ancient extinction nicknamed 'the Great Dying'?"},{"id":"permian-ocean-suffocate","t":"long-ago","q":"Why did the oceans run out of breathable oxygen during the Permian extinction?"},{"id":"permian-volcanoes","t":"long-ago","q":"Why did volcanoes on the other side of the world help cause Earth's worst extinction?"},{"id":"persistence-hunting","t":"long-ago","q":"Why could early humans outrun almost any animal, if given enough time?"},{"id":"persistence-hunting-2","t":"long-ago","q":"Why did some hunters chase an animal for hours instead of trying to catch it quickly?"},{"id":"pharaoh-god-king","t":"long-ago","q":"Why did Egyptians think their pharaoh was a living god?"},{"id":"pig-domestication","t":"long-ago","q":"Why were pigs domesticated from wild boar so many separate times?"},{"id":"pit-trap","t":"long-ago","q":"Why did some hunters dig deep pits to catch large animals?"},{"id":"pituri-trade-network","t":"long-ago","q":"Why did a small native plant get carried along trade routes stretching across several deserts?"},{"id":"plague","t":"long-ago","q":"Why did the plague kill so many people?"},{"id":"plants-first-land","t":"long-ago","q":"Why did plants reach dry land millions of years before animals did?"},{"id":"poison-arrow-tips","t":"long-ago","q":"Why did some ancient hunters coat their arrow tips with poison?"},{"id":"poison-safe-to-eat","t":"long-ago","q":"Why doesn't the poison on a hunter's arrow poison the people who later eat the meat?"},{"id":"pompeii-preserved","t":"long-ago","q":"Why do we know so much about daily life in one particular Roman town?"},{"id":"porcelain-china-name","t":"long-ago","q":"Why does fine porcelain share its name with the country that invented it?"},{"id":"possum-skin-cloaks","t":"long-ago","q":"Why were possum-skin cloaks more than just clothing for warmth?"},{"id":"potato-altitude","t":"long-ago","q":"Why were potatoes tamed high in the Andes mountains instead of down in a warm valley?"},{"id":"printing-press","t":"long-ago","q":"Why was the printing press such a big deal?"},{"id":"private-property-farming","t":"long-ago","q":"Why did the idea of owning a patch of land only really take off after farming began?"},{"id":"profile-art","t":"long-ago","q":"Why did Egyptian paintings show people's heads and legs facing sideways but their eyes and chest facing forward?"},{"id":"puebloan-cliff-dwellings","t":"long-ago","q":"Why did Ancestral Puebloans build homes into cliff faces?"},{"id":"pyramid-alignment","t":"long-ago","q":"Why are the pyramids lined up so precisely with true north?"},{"id":"pyramid-smooth-casing","t":"long-ago","q":"Why did the Great Pyramid once look smooth and white, not stepped and rough like it does today?"},{"id":"pyramids","t":"long-ago","q":"Why did they build the pyramids?"},{"id":"pyramids-not-aliens","t":"long-ago","q":"Why don't historians think the pyramids needed help from aliens to build?"},{"id":"qin-shi-huang-mercury-immortality","t":"long-ago","q":"Why did an emperor searching for eternal life poison himself instead?"},{"id":"qin-shi-huang-unify-writing","t":"long-ago","q":"Why did China's first emperor force the whole country to use the same writing?"},{"id":"raw-food-chewing-time","t":"long-ago","q":"Why do wild chimpanzees spend hours a day just chewing?"},{"id":"reed-boats","t":"long-ago","q":"Why did early Egyptian boats get built from bundled reeds instead of wooden planks?"},{"id":"reindeer-domestication","t":"long-ago","q":"Why did some Arctic peoples tame reindeer instead of hunting them only?"},{"id":"rice-paddy-flood","t":"long-ago","q":"Why do farmers flood rice fields on purpose?"},{"id":"rigveda-oral","t":"long-ago","q":"Why could ancient Indian priests recite a thousand-verse text without ever writing it down?"},{"id":"rock-art-dating-wasp-nest","t":"long-ago","q":"Why can a mud wasp's nest help date a rock painting underneath it?"},{"id":"rock-art-pigment-mixing","t":"long-ago","q":"Why does ochre rock art painted thousands of years ago still keep its colour today?"},{"id":"roman-aqueduct-gravity","t":"long-ago","q":"Why could Roman aqueducts carry water for a hundred kilometres without a pump?"},{"id":"roman-army-mule","t":"long-ago","q":"Why were Roman soldiers nicknamed Marius's mules?"},{"id":"roman-baths-rooms","t":"long-ago","q":"Why did a Roman bathhouse make you walk through three different rooms?"},{"id":"roman-camp-nightly","t":"long-ago","q":"Why did a Roman army build a full fort every night, even for one night's stop?"},{"id":"roman-citizenship-value","t":"long-ago","q":"Why was Roman citizenship worth so much to conquered peoples?"},{"id":"roman-concrete-secret","t":"long-ago","q":"Why is Roman concrete lasting longer than a lot of concrete poured last century?"},{"id":"roman-glassblowing","t":"long-ago","q":"Why did glass cups suddenly become cheap in the Roman world?"},{"id":"roman-medicine-tools","t":"long-ago","q":"Why have some Roman surgical tools barely changed in two thousand years?"},{"id":"roman-numerals-zero","t":"long-ago","q":"Why did Roman numerals make simple sums so hard?"},{"id":"roman-pepper-trade","t":"long-ago","q":"Why did Rome send enormous amounts of gold to India, worrying its own senators?"},{"id":"roman-roads","t":"long-ago","q":"Why are Roman roads still there?"},{"id":"roman-sailing-season","t":"long-ago","q":"Why did Roman ships mostly avoid the sea for a third of the year?"},{"id":"roman-senate-property","t":"long-ago","q":"Why did you need to be rich to become a Roman senator?"},{"id":"roman-slaves-daily","t":"long-ago","q":"Why did daily life in a wealthy Roman household depend so heavily on enslaved people?"},{"id":"roman-toilets-sponge","t":"long-ago","q":"Why didn't Roman public toilets have any stalls for privacy?"},{"id":"roman-tria-nomina","t":"long-ago","q":"Why did Roman citizens often have three names?"},{"id":"roman-two-consuls","t":"long-ago","q":"Why did Rome choose two consuls instead of one king?"},{"id":"roman-women-rights","t":"long-ago","q":"Why could a Roman woman own property but not vote?"},{"id":"romans-reclined-eating","t":"long-ago","q":"Why did wealthy Romans lie down to eat dinner instead of sitting?"},{"id":"rosetta-stone-2","t":"long-ago","q":"Why does the Rosetta Stone matter so much to historians?"},{"id":"rubicon-crossing","t":"long-ago","q":"Why did crossing one small river count as starting a war?"},{"id":"rusty-rocks","t":"long-ago","q":"Why do rust-red striped rocks tell us exactly when Earth's air changed?"},{"id":"salary-salt-origin","t":"long-ago","q":"Why does the word salary come from the Latin word for salt?"},{"id":"sanchi-stupa","t":"long-ago","q":"Why is a dome-shaped mound at Sanchi one of the oldest stone structures still standing in India?"},{"id":"sandy-bread-teeth","t":"long-ago","q":"Why did eating Egyptian bread wear down people's teeth so badly?"},{"id":"sanskrit-grammar-panini","t":"long-ago","q":"Why did one grammarian's rules for Sanskrit stay almost unchanged for 2,500 years?"},{"id":"sargon-first-empire","t":"long-ago","q":"Why did one king's conquest of Sumer's cities create the world's first empire?"},{"id":"sauropod-neck","t":"long-ago","q":"Why did sauropods grow such long necks?"},{"id":"sauropod-posture","t":"long-ago","q":"Why didn't sauropods hold their necks up like a giraffe?"},{"id":"scribe-school-years","t":"long-ago","q":"Why did becoming a scribe take years of school in the first cities?"},{"id":"scribe-status","t":"long-ago","q":"Why was being a scribe considered one of the best jobs in ancient Egypt?"},{"id":"sea-crossing-australia","t":"long-ago","q":"Why did reaching Australia 65,000 years ago require open-ocean boats?"},{"id":"sea-crossing-australia-2","t":"long-ago","q":"Why does reaching Australia around 65,000 years ago prove people could already build boats?"},{"id":"seed-grinding-stones","t":"long-ago","q":"Why do some grinding stones count among the oldest bread-making tools in the world?"},{"id":"seismoscope-zhang-heng-dragon","t":"long-ago","q":"Why did a bronze dragon drop a ball to prove a far-off earthquake happened?"},{"id":"sericulture-secret-silk","t":"long-ago","q":"Why did China manage to keep the secret of silk-making for thousands of years?"},{"id":"shell-fish-hooks-torres-strait","t":"long-ago","q":"Why did Torres Strait Islanders shape fish hooks out of shell instead of bone?"},{"id":"shell-middens-evidence","t":"long-ago","q":"Why does a huge pile of old shells on a beach count as one of the best history books archaeologists have?"},{"id":"sickle-gloss-evidence","t":"long-ago","q":"Why does a shiny gloss on an ancient stone blade prove someone harvested wild grain with it?"},{"id":"silk-moth-cocoon-process","t":"long-ago","q":"Why does making silk mean boiling a caterpillar's cocoon before it can hatch?"},{"id":"silk-road-envoy-military","t":"long-ago","q":"Why did an envoy sent to find an army ally end up opening a trade route instead?"},{"id":"silk-road-not-single-road","t":"long-ago","q":"Why is the \"Silk Road\" not actually one single road at all?"},{"id":"silkworm-domestication","t":"long-ago","q":"Why can't domesticated silk moths fly anymore?"},{"id":"six-seasons-calendar","t":"long-ago","q":"Why do some Aboriginal calendars use six seasons instead of four?"},{"id":"slash-and-burn-farming","t":"long-ago","q":"Why did some early farmers deliberately burn a patch of forest before planting?"},{"id":"smallest-dinosaur","t":"long-ago","q":"Why were some dinosaurs as small as a chicken?"},{"id":"smoking-ceremony-purpose","t":"long-ago","q":"Why does burning particular native leaves still open important gatherings today?"},{"id":"snowball-earth","t":"long-ago","q":"Why did the whole Earth once freeze over, oceans and all?"},{"id":"socrates-death","t":"long-ago","q":"Why was the philosopher Socrates put to death by his own city?"},{"id":"songlines-as-maps","t":"long-ago","q":"Why can a song be as accurate as a map for finding your way across the desert?"},{"id":"sparta-cliff-myth","t":"long-ago","q":"Why do people say Spartans threw weak babies off a cliff, and is it true?"},{"id":"spartan-boys-agoge","t":"long-ago","q":"Why did Spartan boys leave home at the age of seven?"},{"id":"spartan-helots","t":"long-ago","q":"Why were most people in Sparta not actually Spartan citizens?"},{"id":"spear-thrower-speed","t":"long-ago","q":"Why can a spear-thrower fling a spear farther than an arm alone?"},{"id":"sphinx-nose","t":"long-ago","q":"Why is the Great Sphinx's nose missing?"},{"id":"sphinx-shape","t":"long-ago","q":"Why does the Great Sphinx have a lion's body and a human head?"},{"id":"spice-trade-monsoon","t":"long-ago","q":"Why did learning the monsoon winds change how fast ships could sail between India and Rome?"},{"id":"spine-s-curve-2","t":"long-ago","q":"Why is the human spine curved like a stretched-out S?"},{"id":"spinifex-resin-glue","t":"long-ago","q":"Why did a scratchy desert grass turn out to be one of the most useful plants in Central Australia?"},{"id":"spinosaurus-swim","t":"long-ago","q":"Why do scientists think Spinosaurus could swim?"},{"id":"stegosaurus-brain","t":"long-ago","q":"Why didn't Stegosaurus really have a second brain in its bottom?"},{"id":"stegosaurus-plates","t":"long-ago","q":"Why did Stegosaurus have plates along its back?"},{"id":"step-pyramid","t":"long-ago","q":"Why was Egypt's very first pyramid built like a staircase instead of smooth sides?"},{"id":"stone-survives-wood-rots","t":"long-ago","q":"Why do we find thousands of ancient stone tools but hardly any of their wooden handles?"},{"id":"stonehenge","t":"long-ago","q":"Why did people build Stonehenge?"},{"id":"strigil-no-soap","t":"long-ago","q":"Why did Romans scrape themselves clean with a curved blade instead of soap?"},{"id":"string-invention","t":"long-ago","q":"Why do some archaeologists call string one of the most powerful inventions ever made?"},{"id":"stromatolites-australia","t":"long-ago","q":"Why does Australia have the best living stromatolites left in the world?"},{"id":"stromatolites-disappear","t":"long-ago","q":"Why did stromatolites almost disappear once animals evolved?"},{"id":"stromatolites-rocks","t":"long-ago","q":"Why are stromatolites sometimes called 'living rocks'?"},{"id":"sumer-cradle-name","t":"long-ago","q":"Why is Sumer often called \"the cradle of civilization\"?"},{"id":"sumerian-base-sixty","t":"long-ago","q":"Why did counting sixty of something make sense to Sumerian city accountants?"},{"id":"surplus-and-specialists","t":"long-ago","q":"Why couldn't potters, priests or soldiers exist before farming produced surplus food?"},{"id":"sushruta-surgery","t":"long-ago","q":"Why did an ancient Indian surgeon rebuild noses using skin from a patient's own forehead?"},{"id":"tablets-saved-by-fire","t":"long-ago","q":"Why do archaeologists sometimes have ancient fires to thank for saved clay tablets?"},{"id":"taxila-learning-hub","t":"long-ago","q":"Why did one ancient city near India's northwest frontier become a magnet for students and traders?"},{"id":"tea-legend-vs-evidence","t":"long-ago","q":"Why is the famous story of tea's discovery probably a legend, not history?"},{"id":"temple-owns-farmland","t":"long-ago","q":"Why did temples end up owning much of a Sumerian city's farmland?"},{"id":"teotihuacan-mystery","t":"long-ago","q":"Why does nobody know for certain who ruled the giant city of Teotihuacan?"},{"id":"terracing-hillsides","t":"long-ago","q":"Why did some farmers carve their hillsides into wide flat steps?"},{"id":"terracotta-army-discovery-well","t":"long-ago","q":"Why did farmers digging a well stumble onto an emperor's buried army?"},{"id":"terracotta-army-mold-faces","t":"long-ago","q":"Why do the Terracotta Army's thousands of faces all look different?"},{"id":"testudo-formation","t":"long-ago","q":"Why did Roman soldiers lock their shields into a tortoise shape?"},{"id":"threshing-winnowing","t":"long-ago","q":"Why did farmers throw grain up into the air after harvesting it?"},{"id":"thumbs-down-myth","t":"long-ago","q":"Why is the thumbs-down-means-kill gesture probably not really Roman?"},{"id":"titanic","t":"long-ago","q":"Why did the Titanic sink?"},{"id":"toga-purple-stripe","t":"long-ago","q":"Why did a purple stripe on a toga mark someone out in Rome?"},{"id":"tomb-robbers","t":"long-ago","q":"Why were ancient Egyptian tombs robbed so often, so quickly?"},{"id":"toolmakers-choose-rock","t":"long-ago","q":"Why didn't ancient toolmakers just pick up any rock lying around?"},{"id":"torres-strait-outrigger-canoes","t":"long-ago","q":"Why did Torres Strait Islander sailors add a long pole to the side of their canoes?"},{"id":"torres-strait-star-navigation","t":"long-ago","q":"Why could Torres Strait Islander sailors find a tiny island with no coastline in sight?"},{"id":"trade-routes-continent-wide","t":"long-ago","q":"Why could a tool made on one coast of Australia turn up thousands of kilometres away on the other?"},{"id":"trex-arms","t":"long-ago","q":"Why were T. rex's arms so short?"},{"id":"trex-vision","t":"long-ago","q":"Why didn't T. rex only see things that moved?"},{"id":"triceratops-horns","t":"long-ago","q":"Why did Triceratops have three horns on its face?"},{"id":"trilobite-curl","t":"long-ago","q":"Why did trilobites roll up into a tight ball to defend themselves?"},{"id":"trilobite-eyes","t":"long-ago","q":"Why were trilobite eyes made of clear crystal instead of soft tissue?"},{"id":"trilobite-success","t":"long-ago","q":"Why did trilobites survive for over 250 million years, longer than the dinosaurs?"},{"id":"trojan-war-legend","t":"long-ago","q":"Why can't historians say for certain whether the Trojan War really happened?"},{"id":"turkey-domestication-mesoamerica","t":"long-ago","q":"Why was the turkey one of the few birds tamed in the Americas?"},{"id":"twisted-rope-strength","t":"long-ago","q":"Why does twisting fibres together make a rope far stronger than any one strand alone?"},{"id":"tyrian-purple-cost","t":"long-ago","q":"Why was purple dye once worth more than its weight in gold?"},{"id":"uniform-weights-trade","t":"long-ago","q":"Why did early cities need one uniform set of weights for trading fairly?"},{"id":"upanishads-questions","t":"long-ago","q":"Why did ancient Indian philosophers write down their ideas as conversations, not commands?"},{"id":"ur-tomb-many-buried","t":"long-ago","q":"Why did archaeologists find dozens of people buried together in one ancient tomb at Ur?"},{"id":"uruk-first-city","t":"long-ago","q":"Why is Uruk considered the world's first true city?"},{"id":"uruk-traders-far","t":"long-ago","q":"Why did Uruk send its traders hundreds of kilometres from home?"},{"id":"ushabti-figures","t":"long-ago","q":"Why did Egyptians bury tiny statues called ushabti with the dead?"},{"id":"varna-origins-nuance","t":"long-ago","q":"Why is it hard to say exactly how India's varna system of four broad classes began?"},{"id":"vedic-cattle-wealth","t":"long-ago","q":"Why was a Vedic family's wealth counted in cows rather than coins?"},{"id":"vedic-horse-sacrifice","t":"long-ago","q":"Why did a Vedic king let a chosen horse wander free for a year before a huge ceremony?"},{"id":"vedic-iron-age","t":"long-ago","q":"Why did iron tools change farming on the Ganges plain more than in the older Indus region?"},{"id":"vedic-rivers-names","t":"long-ago","q":"Why do the rivers named in the Rigveda help historians work out how old it really is?"},{"id":"velarium-awning","t":"long-ago","q":"Why did it take a team of sailors to shade the Colosseum?"},{"id":"velociraptor-real","t":"long-ago","q":"Why was the real Velociraptor nothing like the one in films?"},{"id":"vigiles-firefighters","t":"long-ago","q":"Why did Rome create the first professional firefighting force?"},{"id":"vikings","t":"long-ago","q":"Why did the Vikings raid?"},{"id":"vomitorium-myth","t":"long-ago","q":"Why wasn't a vomitorium a room for being sick in?"},{"id":"walk-upright-origin","t":"long-ago","q":"Why did our ancestors start walking on two legs?"},{"id":"walls-tax-trade","t":"long-ago","q":"Why did city walls have as much to do with taxing traders as fighting enemies?"},{"id":"warlpiri-sign-language","t":"long-ago","q":"Why can some Aboriginal groups hold a whole conversation without saying a single word?"},{"id":"water-buffalo-rice","t":"long-ago","q":"Why did rice farmers rely on water buffalo rather than horses or cattle?"},{"id":"wax-tablet-writing","t":"long-ago","q":"Why did Roman schoolchildren write on wax instead of paper?"},{"id":"wealth-inequality-farming","t":"long-ago","q":"Why did farming societies end up with far greater gaps between rich and poor than hunter-gatherer groups?"},{"id":"weaning-food-farming","t":"long-ago","q":"Why could farming mothers have babies more often than hunter-gatherer mothers?"},{"id":"weighing-heart","t":"long-ago","q":"Why did Egyptians believe your heart got weighed after you died?"},{"id":"wheat-hybrid-new","t":"long-ago","q":"Why is bread wheat a plant that never existed in the wild at all?"},{"id":"wheat-self-pollinate","t":"long-ago","q":"Why did wheat's ability to pollinate itself make it so much easier to tame?"},{"id":"wheat-shatter","t":"long-ago","q":"Why does farmed wheat hang onto its own seeds instead of dropping them like wild wheat?"},{"id":"wheel","t":"long-ago","q":"Why did the wheel take so long to invent?"},{"id":"wheelbarrow-one-wheel-china","t":"long-ago","q":"Why did an ancient Chinese wheelbarrow only need one wheel to carry a heavy load?"},{"id":"woomera-multi-tool","t":"long-ago","q":"Why was a woomera more than just a spear-thrower to Aboriginal hunters?"},{"id":"workers-strike","t":"long-ago","q":"Why do historians point to ancient Egypt for history's first recorded labour strike?"},{"id":"woven-basket-regional-styles","t":"long-ago","q":"Why does a woven basket from one part of Australia look completely different from one made elsewhere?"},{"id":"writing","t":"long-ago","q":"Why was writing invented?"},{"id":"writing-tally-first","t":"long-ago","q":"Why was the very first writing just a tally of grain and beer, not a story?"},{"id":"yellow-river-flooding-china-sorrow","t":"long-ago","q":"Why is the Yellow River nicknamed \"China's Sorrow\"?"},{"id":"younger-dryas-farming","t":"long-ago","q":"Why did a sudden cold snap possibly help push people toward farming?"},{"id":"zero-placeholder-nuance","t":"long-ago","q":"Why is \"India invented zero\" not quite the full story?"},{"id":"zheng-he-treasure-fleet","t":"long-ago","q":"Why did a Chinese admiral's ships dwarf Columbus's fleet decades before he sailed?"},{"id":"zhou-dynasty-iron-farming","t":"long-ago","q":"Why did switching from bronze to iron tools change farming in ancient China?"},{"id":"ziggurat-centre","t":"long-ago","q":"Why did Sumerian cities build a giant stepped tower right at the centre?"},{"id":"ziggurat-mud-brick","t":"long-ago","q":"Why was the Ziggurat of Ur built from mud brick instead of stone?"},{"id":"zoonotic-disease-origin","t":"long-ago","q":"Why did living closely with farm animals give humans brand-new diseases?"},{"id":"allspice-one-spice","t":"food","q":"Why is allspice a single spice, not a mix of spices, despite the name?"},{"id":"amaranth-pop","t":"food","q":"Why can amaranth seeds be popped just like popcorn?"},{"id":"anchovy-melt-sauce","t":"food","q":"Why do anchovies seem to \"melt away\" into nothing when cooked in a sauce?"},{"id":"apple-brown","t":"food","q":"Why does a cut apple go brown?"},{"id":"apple-float","t":"food","q":"Why do apples float in water?"},{"id":"apple-graft","t":"food","q":"Why do apple trees have to be grown by grafting, not just planting a pip?"},{"id":"apple-juice-cloudy","t":"food","q":"Why is some apple juice cloudy and some crystal clear?"},{"id":"apple-pip-different","t":"food","q":"Why won't an apple pip grow into the same kind of apple?"},{"id":"apple-pip-poison","t":"food","q":"Why are apple pips mildly poisonous?"},{"id":"apple-storage-sleep","t":"food","q":"Why can shop apples still be crunchy months after they were picked?"},{"id":"artificial-sweeteners","t":"food","q":"Why can some sweeteners taste sweet while barely adding any kilojoules?"},{"id":"asafoetida-smell-change","t":"food","q":"Why does a spice that smells like rotten onions taste savoury once it hits hot oil?"},{"id":"avocado-no-ripen-tree","t":"food","q":"Why won't an avocado ripen while it's still hanging on the tree?"},{"id":"avocado-pit-myth","t":"food","q":"Why doesn't leaving the pit in guacamole actually stop it from browning?"},{"id":"babies-digest-lactose","t":"food","q":"Why can babies drink milk easily when many grown-ups can't?"},{"id":"bagels-boiled","t":"food","q":"Why are bagels boiled before they're baked?"},{"id":"baguette-slash-angle","t":"food","q":"Why are baguette slashes cut at an angle instead of straight down?"},{"id":"baking-powder-instant","t":"food","q":"Why does baking powder make things rise without any waiting around?"},{"id":"banana-berry-myth","t":"food","q":"Why is a banana a berry but a strawberry isn't?"},{"id":"banana-clone","t":"food","q":"Why are nearly all the bananas in the world genetically identical?"},{"id":"banana-disease-risk","t":"food","q":"Why could one disease wipe out the world's banana supply?"},{"id":"banana-no-seeds","t":"food","q":"Why don't the bananas you eat have any seeds inside?"},{"id":"banana-ripen","t":"food","q":"Why does one banana ripen the others?"},{"id":"banana-ripen-sweet","t":"food","q":"Why does an unripe banana taste starchy while a ripe one tastes sweet?"},{"id":"barley-malting","t":"food","q":"Why are barley grains allowed to sprout before they're dried again?"},{"id":"bees-make-honey","t":"food","q":"Why do bees turn nectar into honey instead of just storing the sugar water?"},{"id":"beet-cane-same-taste","t":"food","q":"Why can't you taste any difference between beet sugar and cane sugar?"},{"id":"beet-cold-climate","t":"food","q":"Why is sugar beet grown in places too cold for sugar cane?"},{"id":"beetroot-pink-urine","t":"food","q":"Why can eating beetroot turn some people's wee pink?"},{"id":"black-pepper-piperine","t":"food","q":"Why is the heat in black pepper caused by a totally different chemical than the heat in chilli?"},{"id":"blackberry-raspberry-core","t":"food","q":"Why does a raspberry leave its core on the bush when picked, but a blackberry doesn't?"},{"id":"blackstrap-bitter","t":"food","q":"Why does blackstrap molasses taste so much more bitter than golden syrup?"},{"id":"blood-orange-red","t":"food","q":"Why does a blood orange turn red inside while looking like a normal orange outside?"},{"id":"blueberry-dusty","t":"food","q":"Why are blueberries covered in a dusty-looking coating?"},{"id":"brassica-one-species","t":"food","q":"Why are cabbage, broccoli, cauliflower and brussels sprouts all the same plant?"},{"id":"bread-holes","t":"food","q":"Why are the holes in bread different sizes in different loaves?"},{"id":"bread-rises","t":"food","q":"Why does bread rise?"},{"id":"bread-sound-hollow","t":"food","q":"Why do bakers tap the bottom of a loaf to check if it's done?"},{"id":"bread-stale","t":"food","q":"Why does bread go hard but a biscuit goes soft?"},{"id":"breakfast","t":"food","q":"Why do we have breakfast?"},{"id":"brioche-golden","t":"food","q":"Why is brioche so much richer and more golden than a plain loaf?"},{"id":"brix-measuring-sugar","t":"food","q":"Why do fruit growers use a device that bends light to measure how sweet a fruit is?"},{"id":"broccoli-flower-buds","t":"food","q":"Why is broccoli actually thousands of tiny unopened flowers?"},{"id":"brown-sugar-bread-soften","t":"food","q":"Why does a slice of bread soften rock-hard brown sugar?"},{"id":"brown-sugar-brick","t":"food","q":"Why does brown sugar turn into a hard brick if you leave the bag open?"},{"id":"brown-sugar-molasses","t":"food","q":"Why is brown sugar just white sugar with molasses stirred back in?"},{"id":"brown-sugar-not-healthier","t":"food","q":"Why isn't brown sugar actually healthier than white sugar?"},{"id":"brussels-sprouts-bitter-taste","t":"food","q":"Why do some people find brussels sprouts intensely bitter while others don't mind them?"},{"id":"buckwheat-not-wheat","t":"food","q":"Why does buckwheat have almost nothing to do with wheat?"},{"id":"buddhas-hand-citrus","t":"food","q":"Why does the Buddha's hand citrus have no juice or pulp at all?"},{"id":"buffalo-milk-creamier","t":"food","q":"Why does buffalo milk make such rich, creamy dairy products?"},{"id":"butter-churn","t":"food","q":"Why do you have to shake cream to make butter?"},{"id":"butter-colour-season","t":"food","q":"Why can butter be more yellow at some times of year than others?"},{"id":"butter-softens-bread","t":"food","q":"Why does adding butter or oil make bread softer?"},{"id":"butter-solid-oil-liquid","t":"food","q":"Why is butter solid at room temperature while cooking oil stays liquid?"},{"id":"buttermilk-name-mismatch","t":"food","q":"Why doesn't store-bought buttermilk actually come from churning butter?"},{"id":"cabbage-smell-strengthens","t":"food","q":"Why does cabbage smell stronger the longer you cook it?"},{"id":"cacao-bean-count","t":"food","q":"Why does a single cacao pod hold about forty beans?"},{"id":"cacao-belt","t":"food","q":"Why can cacao trees only grow in a narrow strip around the equator?"},{"id":"cacao-bitter-theobromine","t":"food","q":"Why is raw cacao so fiercely bitter that nobody drinks it plain?"},{"id":"cacao-currency","t":"food","q":"Why did people in ancient Mexico use cacao beans as money?"},{"id":"cacao-drying","t":"food","q":"Why are cacao beans spread out to dry in the sun after fermenting?"},{"id":"cacao-ferment-colour","t":"food","q":"Why do pale cacao beans turn brown before they're ever roasted?"},{"id":"cacao-ferment-heap","t":"food","q":"Why are fresh cacao beans piled up and covered in leaves before anything else happens to them?"},{"id":"cacao-ferment-heat","t":"food","q":"Why does a heap of fermenting cacao beans grow hot enough to feel feverish?"},{"id":"cacao-flower-midge","t":"food","q":"Why do tiny midges do all the pollinating for chocolate?"},{"id":"cacao-grinding","t":"food","q":"Why does grinding roasted cacao turn solid beans into a liquid?"},{"id":"cacao-harvest","t":"food","q":"Why do farmers cut cacao pods open with a machete instead of snapping them off?"},{"id":"cacao-low-pollination","t":"food","q":"Why does a cacao tree turn only a handful of its flowers into pods?"},{"id":"cacao-pod-colours","t":"food","q":"Why do cacao pods ripen in so many different colours?"},{"id":"cacao-pod-trunk","t":"food","q":"Why do cacao pods grow straight out of the tree's trunk?"},{"id":"cacao-pulp","t":"food","q":"Why are cacao beans buried in sweet white slime inside their pod?"},{"id":"cacao-ripening","t":"food","q":"Why does a cacao pod take five months just to ripen?"},{"id":"cacao-roasting","t":"food","q":"Why does roasting turn plain cacao beans into something that finally smells like chocolate?"},{"id":"cacao-shade-grown","t":"food","q":"Why do cacao trees grow best in the shadow of taller trees?"},{"id":"cacao-unfermented","t":"food","q":"Why does a fresh cacao bean taste nothing like chocolate?"},{"id":"cacao-winnowing","t":"food","q":"Why do chocolate makers crack cacao beans open and blow the shells away?"},{"id":"cake-not-kneaded","t":"food","q":"Why isn't cake batter kneaded the way bread dough is?"},{"id":"candy-thermometer","t":"food","q":"Why do old-fashioned lolly makers use a thermometer instead of just watching the pot?"},{"id":"cane-crushed-fast","t":"food","q":"Why does sugar cane have to be crushed within a day of cutting?"},{"id":"cane-juice-green","t":"food","q":"Why is freshly pressed cane juice green instead of white?"},{"id":"capsicum-ripeness-colour","t":"food","q":"Why are green, yellow and red capsicums actually the exact same fruit?"},{"id":"caramel-bitter-burnt","t":"food","q":"Why does caramel turn bitter if it's cooked a few seconds too long?"},{"id":"caramel-colour-change","t":"food","q":"Why does sugar turn brown and change flavour completely when you heat it?"},{"id":"caramel-lemon-juice","t":"food","q":"Why do cooks add a splash of lemon juice when making caramel?"},{"id":"caramel-or-toffee","t":"food","q":"Why can the same melted sugar become runny caramel sauce or hard, snappable toffee?"},{"id":"caramel-turns-grainy","t":"food","q":"Why does melted sugar suddenly turn grainy if you stir it at the wrong moment?"},{"id":"cardamom-pod-seeds","t":"food","q":"Why is cardamom sold as whole pods and not just loose seeds?"},{"id":"carrot-carotenemia","t":"food","q":"Why can eating too many carrots turn your skin orange?"},{"id":"carrot-night-vision-myth","t":"food","q":"Why don't carrots actually give you night vision?"},{"id":"carrot-orange-history","t":"food","q":"Why weren't carrots always orange?"},{"id":"carrot-woody-core","t":"food","q":"Why do some carrots have a tough, pale, woody core?"},{"id":"cauliflower-blanched-white","t":"food","q":"Why does cauliflower stay pale white while broccoli turns green?"},{"id":"caviar-expensive","t":"food","q":"Why is caviar, which is really just fish eggs, so expensive?"},{"id":"celery-negative-calorie-myth","t":"food","q":"Why is it a myth that celery has \"negative calories\"?"},{"id":"celery-stringy-fibres","t":"food","q":"Why does celery have those stringy fibres you can pull out?"},{"id":"ceviche-citrus-cooks","t":"food","q":"Why does citrus juice \"cook\" raw fish in ceviche without any heat at all?"},{"id":"cheese","t":"food","q":"Why does cheese exist?"},{"id":"cheese-ammonia-smell","t":"food","q":"Why does overripe cheese sometimes smell like ammonia?"},{"id":"cheese-bloomy-rind","t":"food","q":"Why does brie have a soft white fuzzy skin?"},{"id":"cheese-blue-veins","t":"food","q":"Why does blue cheese have blue-green streaks running through it?"},{"id":"cheese-cheddar-sharper","t":"food","q":"Why does cheddar taste sharper the older it gets?"},{"id":"cheese-cottage-lumpy","t":"food","q":"Why is cottage cheese lumpy but cream cheese smooth?"},{"id":"cheese-crystals-crunch","t":"food","q":"Why do some aged cheeses like gouda have crunchy white specks?"},{"id":"cheese-curds-squeak","t":"food","q":"Why do fresh cheese curds squeak against your teeth?"},{"id":"cheese-feta-brine","t":"food","q":"Why is feta cheese kept sitting in salty water?"},{"id":"cheese-fondue-smooth","t":"food","q":"Why does melted cheese fondue stay smooth instead of turning stringy or clumpy?"},{"id":"cheese-fridge-rubbery","t":"food","q":"Why does cold cheese feel rubbery straight out of the fridge?"},{"id":"cheese-goat-tangy","t":"food","q":"Why does goat cheese taste tangier than cheese made from cow's milk?"},{"id":"cheese-gouda-caramel","t":"food","q":"Why does aged gouda sometimes taste a bit like caramel?"},{"id":"cheese-grilled-crust","t":"food","q":"Why does a grilled cheese sandwich get a crispy golden crust while the cheese inside stays gooey?"},{"id":"cheese-halloumi-squeak","t":"food","q":"Why does halloumi squeak when you bite it?"},{"id":"cheese-holes-swiss","t":"food","q":"Why does Swiss cheese have holes?"},{"id":"cheese-maggot-casu-marzu","t":"food","q":"Why does one traditional cheese have live maggots jumping around inside it?"},{"id":"cheese-mascarpone-creamy","t":"food","q":"Why is mascarpone so much creamier than most other cheese?"},{"id":"cheese-melts-heat","t":"food","q":"Why does cheese melt when it's heated?"},{"id":"cheese-mice-myth","t":"food","q":"Why do cartoons always show mice loving cheese?"},{"id":"cheese-mould-safe-eat","t":"food","q":"Why is mould dangerous in some cheese but perfectly fine to eat in others?"},{"id":"cheese-mozzarella-stretch","t":"food","q":"Why does mozzarella stretch into long stringy strands?"},{"id":"cheese-nightmares-myth","t":"food","q":"Why do people say eating cheese before bed gives you nightmares?"},{"id":"cheese-orange-colour","t":"food","q":"Why is some cheese orange and some white?"},{"id":"cheese-paneer-no-melt","t":"food","q":"Why doesn't paneer melt when you fry or curry it?"},{"id":"cheese-parmesan-crunch","t":"food","q":"Why does aged parmesan have crunchy white specks in it?"},{"id":"cheese-parmesan-years","t":"food","q":"Why does parmesan need to age for so many years before it's ready to eat?"},{"id":"cheese-pizza-stringy","t":"food","q":"Why does cheese on pizza stretch into long strings when you pull a slice away?"},{"id":"cheese-provolone-pear","t":"food","q":"Why is provolone cheese sometimes shaped like a giant pear?"},{"id":"cheese-pull-photo","t":"food","q":"Why can some melted cheese stretch so far without snapping?"},{"id":"cheese-raw-milk-taste","t":"food","q":"Why does cheese made from raw milk taste different from cheese made with pasteurised milk?"},{"id":"cheese-rennet-curdle","t":"food","q":"Why does adding rennet to milk make it turn solid?"},{"id":"cheese-ricotta-whey","t":"food","q":"Why is ricotta made from whey instead of milk?"},{"id":"cheese-rind-edible","t":"food","q":"Why can you eat some cheese rinds but not others?"},{"id":"cheese-rind-forms","t":"food","q":"Why does cheese grow a hard rind?"},{"id":"cheese-roquefort-caves","t":"food","q":"Why is Roquefort cheese only made in one set of caves in France?"},{"id":"cheese-salt-added","t":"food","q":"Why do cheesemakers always add salt to cheese?"},{"id":"cheese-smell-feet","t":"food","q":"Why does some cheese smell like feet?"},{"id":"cheese-smoked-flavour","t":"food","q":"Why does smoked cheese taste smoky?"},{"id":"cheese-solid-not-liquid","t":"food","q":"Why does cheese stay solid even though the milk it's made from is a liquid?"},{"id":"cheese-string-peels","t":"food","q":"Why does string cheese peel apart into thin strings?"},{"id":"cheese-sweats-oil","t":"food","q":"Why does cheese sometimes look oily or sweaty on the outside?"},{"id":"cheese-washed-rind-orange","t":"food","q":"Why do some cheese rinds turn bright orange and smell strong?"},{"id":"cheese-wax-coat","t":"food","q":"Why do cheesemakers coat some cheese wheels in coloured wax?"},{"id":"cheese-wheel-shape","t":"food","q":"Why is cheese traditionally made in big round wheels?"},{"id":"cheese-wheels-turned","t":"food","q":"Why do cheesemakers keep turning big wheels of cheese while they age?"},{"id":"cherry-skin-split","t":"food","q":"Why do cherries and other stonefruit split their skins after heavy rain?"},{"id":"cherry-stone-poison","t":"food","q":"Why is it dangerous to crack open and eat a cherry stone?"},{"id":"chilli-bird-seed","t":"food","q":"Why don't birds feel a chilli's burn the way people do?"},{"id":"chilli-heat-varies-growing","t":"food","q":"Why can two chillies from the same plant differ wildly in heat?"},{"id":"chilli-hot","t":"food","q":"Why is chilli hot?"},{"id":"chocolate-bar-history","t":"food","q":"Why didn't anyone eat a solid bar of chocolate until the 1800s?"},{"id":"chocolate-bloom-fat","t":"food","q":"Why does chocolate sometimes grow a dusty white film after sitting in a warm cupboard?"},{"id":"chocolate-bloom-mould","t":"food","q":"Why is that white film on old chocolate safe to eat, even though it looks like mould?"},{"id":"chocolate-bloom-sugar","t":"food","q":"Why does chocolate stored in the fridge sometimes turn gritty and pale?"},{"id":"chocolate-dogs-danger","t":"food","q":"Why can a small block of chocolate make a dog seriously ill?"},{"id":"chocolate-dogs-dark","t":"food","q":"Why is dark chocolate far more dangerous to a dog than milk chocolate?"},{"id":"chocolate-melt","t":"food","q":"Why does chocolate melt in your mouth but not in your hand?"},{"id":"chocolate-smooth","t":"food","q":"Why does good chocolate feel silky instead of gritty on your tongue?"},{"id":"chocolate-snap","t":"food","q":"Why does properly made chocolate snap cleanly instead of bending?"},{"id":"chocolate-sugar-europe","t":"food","q":"Why did chocolate turn from a bitter drink into a sweet treat once it reached Europe?"},{"id":"chocolate-tempering","t":"food","q":"Why do chocolate makers heat and cool the very same chocolate over and over?"},{"id":"chocolate-untempered","t":"food","q":"Why does chocolate that skipped tempering turn dull and soft instead of glossy and firm?"},{"id":"chocolate-word-origin","t":"food","q":"Why does the word \"chocolate\" come from a word meaning \"bitter water\"?"},{"id":"cinnamon-bark-curl","t":"food","q":"Why does a cinnamon stick curl into a tight little scroll?"},{"id":"citrus-family-tree","t":"food","q":"Why are oranges, lemons, limes and grapefruits all mixes of just a few original citrus fruits?"},{"id":"citrus-pith-bitter","t":"food","q":"Why is the white layer under citrus peel so bitter?"},{"id":"citrus-zest-spray","t":"food","q":"Why does zesting a lemon spray a fine mist into the air?"},{"id":"clotted-cream-thick","t":"food","q":"Why does clotted cream form such a thick, crusty layer?"},{"id":"clove-numbs-mouth","t":"food","q":"Why can chewing a clove numb your mouth?"},{"id":"cocoa-butter-press","t":"food","q":"Why is cacao paste squeezed to split it into two very different products?"},{"id":"cocoa-butter-uses","t":"food","q":"Why does cocoa butter end up in lip balm and lotion, not just chocolate?"},{"id":"cocoa-powder-fat","t":"food","q":"Why is cocoa powder almost fat-free when cacao beans are half fat?"},{"id":"cocoa-west-africa","t":"food","q":"Why does most of the world's chocolate start on small farms in West Africa?"},{"id":"coconut-classify","t":"food","q":"Why is a coconut a fruit, a nut and a seed all at once?"},{"id":"coconut-young-vs-mature","t":"food","q":"Why does a young green coconut hold cups of water but hardly any meat, while an old brown one is the opposite?"},{"id":"coffee-awake","t":"food","q":"Why does coffee keep grown-ups awake?"},{"id":"cold-taste","t":"food","q":"Why does food taste boring when you have a cold?"},{"id":"conching-invention","t":"food","q":"Why was chocolate a gritty, crumbly food until one Swiss inventor changed it in 1879?"},{"id":"conching-time","t":"food","q":"Why can it take several days of constant grinding to finish a batch of fine chocolate?"},{"id":"cooking","t":"food","q":"Why does cooking change food so much?"},{"id":"cool-before-slicing","t":"food","q":"Why should you let bread cool before slicing it?"},{"id":"corn-kernel-rows-even","t":"food","q":"Why does a corn cob always have an even number of kernel rows?"},{"id":"corn-nixtamalize","t":"food","q":"Why do corn tortillas start with corn soaked in a chemical bath?"},{"id":"corn-silk-one-per-kernel","t":"food","q":"Why does every strand of corn silk lead to exactly one kernel?"},{"id":"corn-syrup-fructose","t":"food","q":"Why is a sweetener made from corn, a vegetable that isn't sweet at all?"},{"id":"cornflour-name-confusion","t":"food","q":"Why does \"cornflour\" mean two completely different things in different countries?"},{"id":"couscous-tiny-pasta","t":"food","q":"Why is couscous really a tiny pasta rather than a separate grain?"},{"id":"cow-milk-after-calf","t":"food","q":"Why does a cow have to have a calf before she can give milk?"},{"id":"cow-milked-often","t":"food","q":"Why are dairy cows milked several times a day?"},{"id":"crab-molt-shell","t":"food","q":"Why does a crab have to shed its entire shell just to grow bigger?"},{"id":"cranberry-bounce-float","t":"food","q":"Why do cranberries bounce and float?"},{"id":"cream-more-fat-than-milk","t":"food","q":"Why does cream have so much more fat than milk?"},{"id":"cream-rises-milk","t":"food","q":"Why does cream rise to the top of milk left standing?"},{"id":"croissant-layers","t":"food","q":"Why does a croissant have so many thin, buttery layers?"},{"id":"croissant-not-kneaded","t":"food","q":"Why is croissant dough not kneaded hard the way bread dough is?"},{"id":"crumpet-holes","t":"food","q":"Why are crumpets full of holes on top but smooth underneath?"},{"id":"crust-brown","t":"food","q":"Why is bread crust brown while the crumb inside stays pale?"},{"id":"crust-crackle-sing","t":"food","q":"Why does a crusty loaf crackle as it cools?"},{"id":"cucumber-bitter-end","t":"food","q":"Why does one end of a cucumber sometimes taste surprisingly bitter?"},{"id":"cumin-caraway-confuse","t":"food","q":"Why do cooks so often mix up cumin and caraway?"},{"id":"curry-leaves-not-curry-powder","t":"food","q":"Why do fresh curry leaves have nothing to do with curry powder?"},{"id":"curry-powder-invented","t":"food","q":"Why is \"curry powder\" a British invention rather than a traditional Indian spice blend?"},{"id":"custard-apple-segments","t":"food","q":"Why does a custard apple's bumpy skin show the outline of segments inside?"},{"id":"dark-chocolate-percent","t":"food","q":"Why does a block of chocolate boast a number like \"70%\" on the wrapper?"},{"id":"dough-rest","t":"food","q":"Why do bakers let dough rest before shaping it?"},{"id":"dough-springs-back","t":"food","q":"Why does dough spring back when you poke it?"},{"id":"dragon-fruit-seeds","t":"food","q":"Why do dragon fruit seeds pass right through you without being digested?"},{"id":"dried-fruit-lasts","t":"food","q":"Why does dried fruit last for months without going off?"},{"id":"dried-fruit-sweeter","t":"food","q":"Why does dried fruit taste far sweeter than the same fruit fresh?"},{"id":"durian-smell","t":"food","q":"Why does durian smell so strong it's banned on trains and in hotels?"},{"id":"edamame-young-soybean","t":"food","q":"Why is edamame just a soybean picked before it's finished growing?"},{"id":"egg-allergy-protein","t":"food","q":"Why can egg white cause a serious allergic reaction in some children?"},{"id":"egg-binder-meatballs","t":"food","q":"Why is egg often mixed into meatballs, meatloaf or veggie patties?"},{"id":"egg-blood-spot","t":"food","q":"Why do some eggs have a tiny red or brown spot in them?"},{"id":"egg-boil-timing","t":"food","q":"Why does the same egg turn out runny, jammy or rock solid depending on boiling time?"},{"id":"egg-broody-hen-sitting","t":"food","q":"Why does a hen sit on her eggs for weeks without eating much at all?"},{"id":"egg-candling","t":"food","q":"Why do farmers shine a bright light through an egg before selling or hatching it?"},{"id":"egg-caviar-actually-different","t":"food","q":"Why is fish roe called something different from a chicken egg, when both are eggs?"},{"id":"egg-century-egg-preserved","t":"food","q":"Why does a preserved century egg turn dark and jelly-like instead of rotting?"},{"id":"egg-cuticle-bloom","t":"food","q":"Why does a freshly laid egg feel slightly different to touch than a washed one?"},{"id":"egg-double-yolk","t":"food","q":"Why do some eggs have two yolks instead of one?"},{"id":"egg-fertilised-supermarket","t":"food","q":"Why can't the eggs you buy at the shop hatch into chicks?"},{"id":"egg-float-freshness-test","t":"food","q":"Why does dropping an egg into water tell you how fresh it is?"},{"id":"egg-free-range-cage-terms","t":"food","q":"Why do egg cartons list terms like free-range, cage-free and barn-laid?"},{"id":"egg-green-ring-yolk","t":"food","q":"Why do some hardboiled eggs get a grey-green ring around the yolk?"},{"id":"egg-incubation-21-days","t":"food","q":"Why does a chicken egg take about 21 days to hatch?"},{"id":"egg-leavening-baking","t":"food","q":"Why do so many cake and pancake recipes rely on egg to help them rise?"},{"id":"egg-mayonnaise-emulsion","t":"food","q":"Why can egg yolk turn oil and vinegar into smooth mayonnaise?"},{"id":"egg-membrane-two-layers","t":"food","q":"Why does a peeled hardboiled egg have a thin skin under the shell?"},{"id":"egg-meringue-sugar","t":"food","q":"Why is sugar added to whisked egg white to make meringue?"},{"id":"egg-naked-vinegar-shell","t":"food","q":"Why can soaking an egg in vinegar for a day make its shell disappear?"},{"id":"egg-nonstick-fry","t":"food","q":"Why does a fried egg stick to some pans but slide freely in others?"},{"id":"egg-oval-shape","t":"food","q":"Why are eggs oval instead of round like a ball?"},{"id":"egg-pasteurised-safe-raw","t":"food","q":"Why can some cartons of egg be labelled safe to eat raw when others aren't?"},{"id":"egg-poach-swirl-vinegar","t":"food","q":"Why do cooks add vinegar and swirl the water when poaching an egg?"},{"id":"egg-quail-duck-comparison","t":"food","q":"Why are quail eggs so much smaller than chicken eggs, and duck eggs bigger?"},{"id":"egg-raw-white-avidin","t":"food","q":"Why is eating a lot of raw egg white not a good idea, even though a little is harmless?"},{"id":"egg-salmonella-cook","t":"food","q":"Why does cooking an egg properly matter for avoiding food poisoning?"},{"id":"egg-scramble-curds","t":"food","q":"Why do scrambled eggs turn into soft lumps instead of one smooth mass?"},{"id":"egg-separating-yolk-white","t":"food","q":"Why does even a speck of yolk ruin egg whites you're trying to whisk?"},{"id":"egg-shell-calcium-eggshell","t":"food","q":"Why is an eggshell almost entirely made of the same mineral as chalk?"},{"id":"egg-shell-colour-breed","t":"food","q":"Why are some eggs brown and some white?"},{"id":"egg-shell-crack-air-cell","t":"food","q":"Why do hardboiled eggs sometimes crack on their own while still boiling?"},{"id":"egg-shell-pores","t":"food","q":"Why is an eggshell covered in thousands of tiny holes?"},{"id":"egg-size-grading","t":"food","q":"Why are eggs sold in sizes like small, medium and large?"},{"id":"egg-souffle-rises","t":"food","q":"Why does a souffle rise dramatically then sink minutes later?"},{"id":"egg-storage-fridge-differs","t":"food","q":"Why do some countries keep eggs in the fridge while others leave them on the shelf?"},{"id":"egg-whisk-foam","t":"food","q":"Why can whisking turn liquid egg white into a stiff, fluffy foam?"},{"id":"egg-white-clear-to-white","t":"food","q":"Why is raw egg white see-through but cooked egg white bright white?"},{"id":"egg-white-thick-vs-thin","t":"food","q":"Why does a fresh egg have thick, gel-like white while an older egg's runs thin?"},{"id":"egg-yolk-attached-white-strand","t":"food","q":"Why is there a stringy white cord attached to the yolk when you crack an egg?"},{"id":"egg-yolk-cholesterol-context","t":"food","q":"Why does egg yolk contain more cholesterol than almost any other everyday food?"},{"id":"egg-yolk-colour","t":"food","q":"Why can egg yolks range from pale yellow to deep orange?"},{"id":"egg-yolk-firmness-fat-water","t":"food","q":"Why does yolk feel so much richer and creamier than egg white?"},{"id":"egg-yolk-membrane-vitelline","t":"food","q":"Why does a yolk hold its round shape instead of spreading flat like the white?"},{"id":"egg-yolk-tears-heat-custard","t":"food","q":"Why does custard turn lumpy if you heat it too fast?"},{"id":"eggplant-salting-myth","t":"food","q":"Why do old recipes say to salt eggplant, even though most cooks skip it now?"},{"id":"eggs-cook","t":"food","q":"Why does an egg go hard when you cook it?"},{"id":"enamel-recovery-time","t":"food","q":"Why does your tooth enamel need time to recover after something sugary?"},{"id":"fig-short-life","t":"food","q":"Why can you almost never buy a truly fresh fig far from where it grew?"},{"id":"fig-wasp-myth","t":"food","q":"Why is a fig actually a flower turned inside out?"},{"id":"finger-lime-caviar","t":"food","q":"Why is the finger lime nicknamed 'citrus caviar'?"},{"id":"fish-bones-pin-hidden","t":"food","q":"Why do some fish fillets have extra tiny bones hidden inside the flesh?"},{"id":"fish-chips-batter-crisp","t":"food","q":"Why does a beer batter puff up bubbly and crisp around fried fish?"},{"id":"fish-eyes-freshness","t":"food","q":"Why do fishmongers check a fish's eyes to tell how fresh it is?"},{"id":"fish-farming-aquaculture-grow","t":"food","q":"Why is more of the seafood we eat now farmed instead of caught wild?"},{"id":"fish-gills-breathe","t":"food","q":"Why can a fish breathe underwater but drown if it's out of water for too long?"},{"id":"fish-memory-myth","t":"food","q":"Why is it wrong to say fish only remember things for three seconds?"},{"id":"fish-oil-omega3-good","t":"food","q":"Why do doctors so often talk about the oil found in oily fish?"},{"id":"fish-sauce-strong-smell","t":"food","q":"Why does fish sauce smell so sharp on its own but taste savoury once it's cooked into food?"},{"id":"fish-scale-rainbow-shine","t":"food","q":"Why do some fish scales flash rainbow colours when they catch the light?"},{"id":"fish-scales-shingles","t":"food","q":"Why are fish scales arranged like tiles on a roof?"},{"id":"fish-skin-crispy-press","t":"food","q":"Why do chefs press a fish fillet flat in the pan with a spatula while it cooks?"},{"id":"fish-smell-fresh-vs-off","t":"food","q":"Why does truly fresh fish barely smell like \"fish\" at all?"},{"id":"fish-stock-bones-broth","t":"food","q":"Why do chefs simmer fish bones and heads into stock instead of throwing them away?"},{"id":"fizzy-bubbles","t":"food","q":"Why is lemonade fizzy?"},{"id":"flatbread-no-rise","t":"food","q":"Why don't flatbreads like tortillas need time to rise?"},{"id":"flour-fortified","t":"food","q":"Why do some flours have vitamins added back into them after milling?"},{"id":"flour-types","t":"food","q":"Why do recipes ask for different types of flour?"},{"id":"focaccia-dimples","t":"food","q":"Why do bakers poke dimples all over focaccia before baking it?"},{"id":"fridge-food","t":"food","q":"Why does food last longer in the fridge?"},{"id":"fruit-bribery","t":"food","q":"Why do plants bother making sweet, juicy fruit at all?"},{"id":"fruit-cold-less-sweet","t":"food","q":"Why does fruit taste less sweet straight out of the fridge?"},{"id":"fruit-colour-change","t":"food","q":"Why do fruits change colour as they ripen?"},{"id":"fruit-keep-ripening","t":"food","q":"Why do some fruits keep ripening after they're picked, but others never do?"},{"id":"fruit-mould-spread","t":"food","q":"Why does one soft spot on a fruit turn to mould so fast?"},{"id":"fruit-parthenocarpy","t":"food","q":"Why can some fruit grow without its flower ever being pollinated?"},{"id":"fruit-soften","t":"food","q":"Why does ripe fruit turn soft when unripe fruit is hard?"},{"id":"fruit-sweet-reward","t":"food","q":"Why is ripe fruit sweet?"},{"id":"fruit-thinning","t":"food","q":"Why do orchardists pull perfectly good baby fruit off the tree before it's even grown?"},{"id":"fruit-unripe-sour","t":"food","q":"Why is unripe fruit sour and hard to eat?"},{"id":"garam-masala-added-late","t":"food","q":"Why is garam masala usually added at the end of cooking rather than the start?"},{"id":"garlic-blue-green-pickle","t":"food","q":"Why can garlic turn an eerie blue-green when pickled or cooked?"},{"id":"garlic-breath","t":"food","q":"Why does garlic stay on your breath for so long?"},{"id":"garlic-clove-split","t":"food","q":"Why does a garlic bulb split into separate cloves instead of staying whole?"},{"id":"ghee-shelf-stable","t":"food","q":"Why doesn't ghee need to be kept in the fridge like butter?"},{"id":"ghost-pepper-record","t":"food","q":"Why did chilli breeders start competing to grow hotter and hotter peppers?"},{"id":"ginger-dried-hotter","t":"food","q":"Why does dried ginger often taste hotter than fresh ginger?"},{"id":"ginger-heat-different","t":"food","q":"Why does ginger's heat feel warm rather than sharp like chilli?"},{"id":"goat-milk-different","t":"food","q":"Why does goat's milk taste and digest differently from cow's milk?"},{"id":"goat-milk-naturally-smoother","t":"food","q":"Why doesn't goat milk separate into a cream layer the way cow milk does?"},{"id":"grape-bloom-yeast","t":"food","q":"Why is grape skin dusted with the same wild yeast that turns juice into wine?"},{"id":"grapefruit-bitter","t":"food","q":"Why is grapefruit so much more bitter than an orange?"},{"id":"grapefruit-medicine","t":"food","q":"Why can grapefruit juice change how a medicine works in your body?"},{"id":"grapefruit-name-clusters","t":"food","q":"Why is grapefruit called \"grape\" fruit when it isn't related to grapes at all?"},{"id":"green-bean-stringless-breeding","t":"food","q":"Why don't most green beans today have the tough string down the side?"},{"id":"grits-hominy","t":"food","q":"Why are corn grits made from corn that's already been through a chemical soak?"},{"id":"homogenisation-mechanism","t":"food","q":"Why doesn't shop milk separate into a layer of cream anymore?"},{"id":"honey","t":"food","q":"Why does honey never go off?"},{"id":"honey-crystals-cloudy","t":"food","q":"Why does honey turn cloudy and grainy in the jar while golden syrup stays clear?"},{"id":"honey-sweeter-than-sugar","t":"food","q":"Why does honey taste sweeter than the same spoonful of white sugar?"},{"id":"horseradish-nose-burn","t":"food","q":"Why does horseradish burn your nose more than your tongue?"},{"id":"hot-oven-spring","t":"food","q":"Why is bread baked in a very hot oven rather than a gentle warm one?"},{"id":"hot-water-more-sugar","t":"food","q":"Why can hot water hold more dissolved sugar than cold water?"},{"id":"human-milk-different-cow-milk","t":"food","q":"Why is human breast milk so different from cow's milk?"},{"id":"ice-cream-soft","t":"food","q":"Why is ice cream soft if it's frozen?"},{"id":"icing-sugar-cornflour","t":"food","q":"Why is there cornflour mixed into a bag of icing sugar?"},{"id":"icing-sugar-fine","t":"food","q":"Why is icing sugar so much finer than the sugar in your cereal bowl?"},{"id":"injera-spongy","t":"food","q":"Why is Ethiopian injera bread spongy with tiny holes all over?"},{"id":"isinglass-fish-bladder-wine","t":"food","q":"Why do some wines and beers use a substance made from fish bladders to clear them?"},{"id":"jackfruit-huge","t":"food","q":"Why is jackfruit the biggest fruit that grows on any tree?"},{"id":"jam-mould-opened","t":"food","q":"Why can jam still grow mould on top, even though it's packed with sugar?"},{"id":"jam-sugar-preserve","t":"food","q":"Why does jam packed with sugar last months in the cupboard unopened?"},{"id":"jelly-sets","t":"food","q":"Why does jelly set?"},{"id":"juice-fibre-loss","t":"food","q":"Why does squeezing fruit into juice leave the fibre behind?"},{"id":"kakadu-plum-vitc","t":"food","q":"Why does the Kakadu plum have more vitamin C than almost any fruit on Earth?"},{"id":"kiwi-jelly-wont-set","t":"food","q":"Why won't a kiwifruit let jelly set?"},{"id":"knead-stretchy","t":"food","q":"Why does kneading make bread dough stretchy?"},{"id":"lactase-pills","t":"food","q":"Why can lactase drops let a lactose-intolerant person still drink milk?"},{"id":"lactose-free-milk-sweet","t":"food","q":"Why does lactose-free milk taste a little sweeter than regular milk?"},{"id":"lactose-intolerance-mechanism","t":"food","q":"Why does milk upset some people's stomachs?"},{"id":"lactose-intolerance-vs-allergy","t":"food","q":"Why is a milk allergy not the same thing as lactose intolerance?"},{"id":"lactose-tolerance-genetic","t":"food","q":"Why can some adults drink milk easily while others can't?"},{"id":"leek-white-blanched","t":"food","q":"Why is the bottom of a leek white while the top is green?"},{"id":"lemon-sour","t":"food","q":"Why does a lemon make you pull a face?"},{"id":"lettuce-pink-rust-ethylene","t":"food","q":"Why do the edges of bagged lettuce sometimes turn pink or rusty brown?"},{"id":"lettuce-wilt-revive","t":"food","q":"Why does wilted lettuce perk back up if you soak it in cold water?"},{"id":"lime-ceviche","t":"food","q":"Why can lime juice 'cook' raw fish without any heat at all?"},{"id":"lime-vs-orange-acid","t":"food","q":"Why are limes and lemons so much more sour than oranges, even though they're all citrus?"},{"id":"lobster-boil-color","t":"food","q":"Why does a lobster turn from blue-black to bright red when it's boiled?"},{"id":"lobster-live-tank","t":"food","q":"Why are lobsters kept alive in tanks right up until they're cooked?"},{"id":"longan-lychee-family","t":"food","q":"Why do lychees and longans taste so similar despite looking different?"},{"id":"lychee-rambutan-hair","t":"food","q":"Why are lychees and rambutans covered in that odd bumpy or hairy skin?"},{"id":"mace-nutmeg-same-fruit","t":"food","q":"Why are mace and nutmeg actually the same fruit?"},{"id":"mandarin-easy-peel","t":"food","q":"Why do mandarins peel apart so much more easily than oranges?"},{"id":"mango-stone","t":"food","q":"Why does a mango have a big flat hairy stone inside?"},{"id":"mangosteen-lobes","t":"food","q":"Why can you tell how many segments are inside a mangosteen without cutting it open?"},{"id":"matzah-flat","t":"food","q":"Why does matzah stay completely flat with no bubbles at all?"},{"id":"maya-aztec-drink","t":"food","q":"Why did the Maya and Aztecs drink their chocolate instead of eating it?"},{"id":"meat-colour-inside-vs-out","t":"food","q":"Why can meat look grey on the outside but still be perfectly fine to eat?"},{"id":"meat-cooked-brown","t":"food","q":"Why does red meat turn brown when you cook it?"},{"id":"meat-marbling-flavour","t":"food","q":"Why does the white streaky fat in meat matter so much to flavour?"},{"id":"meat-rest-after-cooking","t":"food","q":"Why do cooks let meat rest before cutting into it?"},{"id":"meat-tough-tender","t":"food","q":"Why is some meat tough and some meat tender?"},{"id":"mercury-big-fish-limit","t":"food","q":"Why are children told to eat less of certain big fish like tuna and swordfish?"},{"id":"milk-allergy-danger","t":"food","q":"Why can a milk allergy be so much more serious than a stomach upset?"},{"id":"milk-boils-over-fast","t":"food","q":"Why does milk boil over so much faster than water?"},{"id":"milk-calcium-role","t":"food","q":"Why is milk such a rich natural source of calcium?"},{"id":"milk-chocolate-invented","t":"food","q":"Why did milk chocolate have to wait for someone to invent condensed milk first?"},{"id":"milk-fat-percentages","t":"food","q":"Why does milk come in different fat percentages?"},{"id":"milk-froth-steamed","t":"food","q":"Why does steamed milk froth up into foam for a cappuccino?"},{"id":"milk-skin-forms","t":"food","q":"Why does a skin form on top of milk when it's heated?"},{"id":"milk-sour","t":"food","q":"Why does milk go off?"},{"id":"milk-sunlight-flavour","t":"food","q":"Why does milk left near a sunny window taste different faster than milk kept in the dark?"},{"id":"milk-white-colour","t":"food","q":"Why is milk white?"},{"id":"mint-cold","t":"food","q":"Why does mint feel cold?"},{"id":"molasses-leftover","t":"food","q":"Why is molasses the stuff left behind after sugar crystals are removed?"},{"id":"mushroom-dark-growth","t":"food","q":"Why can mushrooms grow perfectly well with no sunlight at all?"},{"id":"mushroom-gills-spores","t":"food","q":"Why are the gills under a mushroom cap covered in something like dust?"},{"id":"mushroom-not-a-plant","t":"food","q":"Why is a mushroom not actually a vegetable at all?"},{"id":"mussel-beard","t":"food","q":"Why do mussels have a stringy \"beard\" you have to pull off before cooking?"},{"id":"mustard-heat-activate","t":"food","q":"Why does mustard powder need water before it turns hot?"},{"id":"mustard-seed-colours","t":"food","q":"Why do mustard seeds come in yellow, brown and black, each with different heat?"},{"id":"naan-chewy","t":"food","q":"Why is naan bread so much chewier and bubblier than a baguette?"},{"id":"navel-orange-twin","t":"food","q":"Why does a navel orange have what looks like a second tiny orange inside it?"},{"id":"nutmeg-toxic-large","t":"food","q":"Why can eating a whole nutmeg make you seriously ill?"},{"id":"oat-porridge-thicken","t":"food","q":"Why does a bowl of dry oats turn into thick porridge?"},{"id":"oat-processing-types","t":"food","q":"Why do rolled oats, steel-cut oats and instant oats all come from the very same grain?"},{"id":"octopus-ink-cloud","t":"food","q":"Why does an octopus squirt a cloud of ink when it's frightened?"},{"id":"olive-bitter-raw","t":"food","q":"Why is a fresh olive picked straight off the tree so bitter you'd spit it out?"},{"id":"one-bad-apple","t":"food","q":"Why did people used to say 'one bad apple spoils the barrel'?"},{"id":"onion-bulb-layers","t":"food","q":"Why is an onion made of layer after layer wrapped around itself?"},{"id":"onion-green-sprout","t":"food","q":"Why does an old onion sometimes grow a green shoot from its middle?"},{"id":"onions-cry","t":"food","q":"Why do onions make you cry?"},{"id":"orange-green-ripe","t":"food","q":"Why can a perfectly ripe orange still be green?"},{"id":"overfishing-stocks-crash","t":"food","q":"Why can the ocean run out of a fish that once seemed endless?"},{"id":"overknead-myth","t":"food","q":"Why is it almost impossible to over-knead bread dough by hand?"},{"id":"overprove-collapse","t":"food","q":"Why can dough collapse if it's left to rise for too long?"},{"id":"oyster-pearl-formed","t":"food","q":"Why does an oyster wrap an irritant inside layer after layer of shell?"},{"id":"oyster-shuck-hard","t":"food","q":"Why is it so hard to prise a raw oyster open with just a knife?"},{"id":"papaya-papain-meat","t":"food","q":"Why is papaya used to tenderise tough meat?"},{"id":"papaya-seed-pepper","t":"food","q":"Why do papaya seeds taste peppery?"},{"id":"paprika-varies","t":"food","q":"Why can paprika range from mild and sweet to intensely smoky?"},{"id":"passionfruit-seeds","t":"food","q":"Why can you eat a passionfruit's crunchy seeds when most fruit seeds aren't eaten?"},{"id":"pasta-al-dente-meaning","t":"food","q":"Why is pasta meant to have a firm bite right at its centre?"},{"id":"pasta-boil","t":"food","q":"Why does pasta need boiling water?"},{"id":"pasta-bronze-die","t":"food","q":"Why does some dried pasta feel rough instead of smooth and shiny?"},{"id":"pasta-durum-semolina","t":"food","q":"Why is pasta usually made from a different wheat than bread?"},{"id":"pasta-egg-vs-dry","t":"food","q":"Why does fresh pasta use egg while dried pasta uses only water?"},{"id":"pasta-extrude-shape","t":"food","q":"Why can the exact same dough become spaghetti, macaroni or penne?"},{"id":"pasta-glass-noodle","t":"food","q":"Why do some noodles turn glassy and see-through once they're cooked?"},{"id":"pasta-gnocchi-potato","t":"food","q":"Why can gnocchi be made from potato instead of wheat?"},{"id":"pasta-ramen-alkaline","t":"food","q":"Why are ramen noodles yellow and springy while spaghetti isn't?"},{"id":"pasta-salt-water-myth","t":"food","q":"Why do cooks salt pasta water when it barely changes how fast it boils?"},{"id":"pasta-shapes-sauce","t":"food","q":"Why are pasta shapes designed around the sauce they're meant to carry?"},{"id":"pasta-spaghetti-break-three","t":"food","q":"Why does a dry stick of spaghetti almost never snap cleanly into just two pieces?"},{"id":"pasta-stuffed-ravioli-seal","t":"food","q":"Why do ravioli edges stay sealed shut in boiling water?"},{"id":"pasta-water-emulsify","t":"food","q":"Why do cooks save a cup of pasta water before draining it away?"},{"id":"pasteurisation-kills-bacteria","t":"food","q":"Why is milk heated before it's sold?"},{"id":"pasteurisation-nutrition-myth","t":"food","q":"Why doesn't pasteurising milk ruin its goodness?"},{"id":"pasteurised-milk-still-fridge","t":"food","q":"Why does pasteurised milk still need to go in the fridge?"},{"id":"pea-pod-count-limit","t":"food","q":"Why don't pea pods hold an endless number of peas?"},{"id":"pea-tendril-climb","t":"food","q":"Why do pea plants grow curly tendrils that reach out and grab things?"},{"id":"peach-cling","t":"food","q":"Why does peach flesh cling tight to the stone in some peaches but fall free in others?"},{"id":"peach-fuzz","t":"food","q":"Why do peaches have fuzzy skin but nectarines don't?"},{"id":"pear-grit","t":"food","q":"Why does a pear have gritty little flecks in its flesh that an apple doesn't?"},{"id":"pear-picked-hard","t":"food","q":"Why are pears deliberately picked hard and green instead of left to ripen on the tree?"},{"id":"pepper-mill-fresh","t":"food","q":"Why does pepper lose its punch soon after it's ground?"},{"id":"pepper-spray-capsaicin","t":"food","q":"Why does pepper spray use the same chemical that makes chilli taste hot?"},{"id":"peppercorn-colours","t":"food","q":"Why can black, white, green and pink peppercorns all come from the same plant?"},{"id":"persimmon-astringent","t":"food","q":"Why is an unripe persimmon so mouth-puckering that ripe ones aren't?"},{"id":"pineapple-crown-regrow","t":"food","q":"Why can you grow a whole new pineapple plant from the leafy top of one you ate?"},{"id":"pineapple-eats-back","t":"food","q":"Why does fresh pineapple sting your tongue the more you eat?"},{"id":"pineapple-fused-flowers","t":"food","q":"Why is a pineapple really made of dozens of fused flowers, not one?"},{"id":"pita-pocket","t":"food","q":"Why does pita bread puff up into a hollow pocket?"},{"id":"pizza-oven-superhot","t":"food","q":"Why does pizza cook in under two minutes in a proper pizza oven?"},{"id":"pizza-stretch-hand","t":"food","q":"Why do pizza makers stretch dough by hand instead of using a rolling pin?"},{"id":"plantain-vs-banana","t":"food","q":"Why do plantains need cooking while bananas don't?"},{"id":"pomegranate-arils","t":"food","q":"Why is a pomegranate packed with hundreds of separate juicy seed pouches instead of one solid flesh?"},{"id":"pomegranate-stain","t":"food","q":"Why does pomegranate juice stain so much more stubbornly than most other fruit juice?"},{"id":"popcorn","t":"food","q":"Why does popcorn pop?"},{"id":"popcorn-why-pops","t":"food","q":"Why does only some corn pop into popcorn?"},{"id":"potato-after-cook-grey","t":"food","q":"Why do some boiled potatoes turn grey after they've cooled?"},{"id":"potato-eyes-sprout","t":"food","q":"Why does a potato left in the pantry grow pale shoots?"},{"id":"potato-green-toxic","t":"food","q":"Why do green patches on a potato mean you should cut them out?"},{"id":"potato-stem-not-root","t":"food","q":"Why is a potato actually a stem and not a root?"},{"id":"powdered-milk-keeps","t":"food","q":"Why can powdered milk sit safely in a cupboard for years?"},{"id":"pretzel-lye-bath","t":"food","q":"Why are pretzels dipped in a chemical bath before they're baked?"},{"id":"processed-meat-different","t":"food","q":"Why do health guidelines treat processed meat differently from fresh meat?"},{"id":"prove-twice","t":"food","q":"Why do some bread recipes need the dough to rise twice?"},{"id":"pumpkin-giant-growth","t":"food","q":"Why can some pumpkins grow to weigh as much as a small car?"},{"id":"punch-down","t":"food","q":"Why do bakers punch down dough after its first rise?"},{"id":"quandong-native-peach","t":"food","q":"Why does the quandong, a native Australian fruit, have one of the hardest seeds of any fruit?"},{"id":"quince-cooking","t":"food","q":"Why do quinces have to be cooked before they're edible, and why do they turn pink?"},{"id":"quinoa-seed-not-grain","t":"food","q":"Why does quinoa need rinsing before it's cooked?"},{"id":"radish-peppery-heat","t":"food","q":"Why do radishes taste peppery hot instead of just earthy like other roots?"},{"id":"raisin-wrinkle","t":"food","q":"Why do raisins wrinkle instead of shrinking smoothly?"},{"id":"raspberry-bumps","t":"food","q":"Why do raspberries fall apart into tiny bumps when you pick them?"},{"id":"raw-milk-risk","t":"food","q":"Why is raw milk riskier to drink than pasteurised milk?"},{"id":"rhubarb-fruit-or-veg","t":"food","q":"Why is rhubarb cooked like a fruit even though it's technically a vegetable?"},{"id":"rice-amylose-fluffy","t":"food","q":"Why do some rices turn out fluffy and others turn sticky?"},{"id":"rice-basmati-aroma","t":"food","q":"Why does basmati rice smell like popcorn while it cooks?"},{"id":"rice-black-pigment","t":"food","q":"Why is black rice actually purple inside?"},{"id":"rice-brown-vs-white","t":"food","q":"Why is brown rice a different colour from white rice, from the very same grain?"},{"id":"rice-cake-puff","t":"food","q":"Why do puffed rice cakes look nothing like a grain of rice?"},{"id":"rice-flour-no-bread","t":"food","q":"Why can't you bake a normal loaf from rice flour alone?"},{"id":"rice-fried-day-old","t":"food","q":"Why does day-old rice fry up better than rice cooked minutes earlier?"},{"id":"rice-glutinous-myth","t":"food","q":"Why is \"glutinous rice\" a misleading name?"},{"id":"rice-mochi-pound","t":"food","q":"Why is mochi pounded instead of just ground into flour?"},{"id":"rice-paella-crust","t":"food","q":"Why do paella cooks avoid stirring the rice at all?"},{"id":"rice-paper-wrapper","t":"food","q":"Why does rice paper turn see-through and bendy in water?"},{"id":"rice-parboiled-process","t":"food","q":"Why is parboiled rice partly cooked before it's even sold?"},{"id":"rice-rinse-starch","t":"food","q":"Why does rinsing rice change how it cooks?"},{"id":"rice-risotto-creamy","t":"food","q":"Why does risotto turn creamy without any cream?"},{"id":"rice-sushi-short-grain","t":"food","q":"Why does sushi rice have to be a short-grain variety?"},{"id":"rice-swells-water","t":"food","q":"Why does a small cup of raw rice turn into three cups once it's cooked?"},{"id":"rice-wild-not-rice","t":"food","q":"Why isn't wild rice actually rice?"},{"id":"rock-candy-clear","t":"food","q":"Why is a rock candy crystal see-through while a spoonful of table sugar looks solid white?"},{"id":"rock-candy-string","t":"food","q":"Why do rock candy crystals need a string or stick to grow on?"},{"id":"roe-not-all-caviar","t":"food","q":"Why isn't every kind of fish egg allowed to be called caviar?"},{"id":"rosaceae-family","t":"food","q":"Why are apples, cherries, almonds and roses all secretly related?"},{"id":"royal-icing-hard","t":"food","q":"Why does royal icing dry rock hard while buttercream icing stays soft?"},{"id":"rye-dense","t":"food","q":"Why is rye bread so much denser than wheat bread?"},{"id":"rye-flour-mixed-wheat","t":"food","q":"Why is rye bread almost always mixed with wheat flour?"},{"id":"saffron-expensive","t":"food","q":"Why is saffron the most expensive spice in the world by weight?"},{"id":"saffron-three-threads","t":"food","q":"Why does each crocus flower give only three strands of saffron?"},{"id":"salmon-color-chart","t":"food","q":"Why do salmon farmers hold a paint-chip-like card up against a fillet?"},{"id":"salmon-pink-source","t":"food","q":"Why isn't salmon naturally pink the way it looks in the supermarket?"},{"id":"salt-bread","t":"food","q":"Why does bread dough need salt?"},{"id":"salt-taste","t":"food","q":"Why does salt make food taste better?"},{"id":"salted-butter-lasts-longer","t":"food","q":"Why does salted butter keep longer than unsalted butter?"},{"id":"sardine-tin-soft-bones","t":"food","q":"Why can you eat the bones in tinned sardines without even noticing them?"},{"id":"sashimi-vs-sushi","t":"food","q":"Why is sashimi a completely different dish from sushi, even though people mix them up?"},{"id":"scoville-test-origin","t":"food","q":"Why was chilli heat first measured by asking people to taste it?"},{"id":"seafood-iodine-thyroid","t":"food","q":"Why is seafood one of the best natural sources of a mineral your body barely needs any of?"},{"id":"seafood-umami-savoury","t":"food","q":"Why does seafood so often taste deeply savoury rather than just salty?"},{"id":"searing-seal-juices-myth","t":"food","q":"Why doesn't searing meat actually 'seal in the juices'?"},{"id":"seedless-not-gmo","t":"food","q":"Why isn't seedless fruit actually 'genetically modified' the way people assume?"},{"id":"seedless-watermelon-white","t":"food","q":"Why do seedless watermelons still have small white seed-shapes inside?"},{"id":"shellfish-allergy-reaction","t":"food","q":"Why can shellfish trigger such a strong allergic reaction in some people?"},{"id":"shrimp-devein-dark-line","t":"food","q":"Why do cooks remove the dark line running down a prawn's back before cooking it?"},{"id":"shrimp-pink-cooked","t":"food","q":"Why do prawns and shrimp turn pink only when you cook them?"},{"id":"sichuan-pepper-tingle","t":"food","q":"Why does Sichuan pepper make your lips tingle instead of burn?"},{"id":"skim-milk-bluish","t":"food","q":"Why can skim milk look faintly bluish instead of pure white?"},{"id":"slash-bread","t":"food","q":"Why do bakers slash the top of a loaf before baking?"},{"id":"smoked-fish-lasts-longer","t":"food","q":"Why does smoking a fish help it last so much longer than a fresh one?"},{"id":"snowpea-edible-pod","t":"food","q":"Why can you eat a whole snow pea pod but not a garden pea pod?"},{"id":"soft-shell-crab-edible","t":"food","q":"Why can you eat a soft-shell crab whole, shell and all?"},{"id":"sorghum-staple","t":"food","q":"Why is sorghum grown as a staple grain in some of the driest farmland on Earth?"},{"id":"soup-warm","t":"food","q":"Why does hot soup warm you up?"},{"id":"sour-cream-intentional","t":"food","q":"Why is sour cream deliberately made sour, unlike cream that's gone off?"},{"id":"sourdough-place","t":"food","q":"Why does sourdough bread taste different in different cities?"},{"id":"sourdough-sour","t":"food","q":"Why does sourdough bread taste sour?"},{"id":"spelt-ancient-gluten","t":"food","q":"Why does spelt make a different kind of dough to modern wheat?"},{"id":"spice-bloom-oil","t":"food","q":"Why do cooks fry whole spices in oil before adding anything else?"},{"id":"spice-hot-countries","t":"food","q":"Why is the food spicier in hot countries?"},{"id":"spice-rotten-meat-myth","t":"food","q":"Why is the story that medieval cooks used spices to hide rotten meat probably false?"},{"id":"spice-tolerance-build","t":"food","q":"Why can people build up a tolerance to spicy food?"},{"id":"spice-trade-value","t":"food","q":"Why were spices once worth more than gold by weight?"},{"id":"spicy-food-endorphins","t":"food","q":"Why do some people come to enjoy the pain of spicy food?"},{"id":"spicy-food-runny-nose","t":"food","q":"Why does spicy food make your nose run?"},{"id":"spinach-cooked-shrink","t":"food","q":"Why does a huge pile of spinach shrink down to almost nothing when cooked?"},{"id":"spinach-iron-myth","t":"food","q":"Why is spinach's reputation as an amazing source of iron mostly a myth?"},{"id":"squid-ink-pasta","t":"food","q":"Why do chefs cook pasta and rice jet-black with squid ink?"},{"id":"star-anise-licorice","t":"food","q":"Why does star anise taste like liquorice even though the two plants aren't related?"},{"id":"star-fruit-kidney-risk","t":"food","q":"Why can star fruit be dangerous for people with kidney problems?"},{"id":"star-fruit-shape","t":"food","q":"Why does a star fruit slice look like a perfect star?"},{"id":"starter-feed","t":"food","q":"Why does a sourdough starter need feeding?"},{"id":"steam-oven","t":"food","q":"Why do bakers add steam to the oven for crusty bread?"},{"id":"stevia-leaf-sweet","t":"food","q":"Why does a leaf called stevia taste hundreds of times sweeter than sugar?"},{"id":"sticky-toffee-teeth","t":"food","q":"Why can sticky toffee harm your teeth more than a fizzy drink gulped down fast?"},{"id":"stonefruit-one-seed","t":"food","q":"Why do peaches, plums and cherries all have one big hard seed in the middle?"},{"id":"strawberry-seeds-outside","t":"food","q":"Why does a strawberry wear its seeds on the outside?"},{"id":"sugar-cane-beet","t":"food","q":"Why is sugar made from two totally different plants?"},{"id":"sugar-dissolve-hot-faster","t":"food","q":"Why does sugar dissolve faster in hot tea than in cold water?"},{"id":"sugar-dissolve-water-oil","t":"food","q":"Why does sugar dissolve in water but not in oil?"},{"id":"sugar-dough-yeast","t":"food","q":"Why can a little sugar help bread dough but too much hurt it?"},{"id":"sugar-good","t":"food","q":"Why does sugar taste so good?"},{"id":"sugar-hyperactivity-myth","t":"food","q":"Why doesn't sugar actually make kids hyperactive?"},{"id":"sugar-not-direct-tooth-rot","t":"food","q":"Why doesn't sugar rot your teeth directly?"},{"id":"sugar-plaque-glue","t":"food","q":"Why does sugar let plaque bacteria glue themselves onto your teeth?"},{"id":"sugar-slavery-history","t":"food","q":"Why is sugar's history tangled up with one of the worst chapters in human history?"},{"id":"sugar-white-gold","t":"food","q":"Why did sugar used to be kept locked away like treasure?"},{"id":"surimi-crab-sticks-fake","t":"food","q":"Why are \"crab sticks\" often made from a completely different fish?"},{"id":"sushi-fish-frozen-first","t":"food","q":"Why is fish meant for raw dishes like sushi usually frozen first, even though it's eaten raw?"},{"id":"sushi-rice-not-raw","t":"food","q":"Why does the word \"sushi\" actually mean the rice, not the fish on top?"},{"id":"sustainable-seafood-label","t":"food","q":"Why do some seafood packets carry a little blue tick label?"},{"id":"sweat-spicy-food","t":"food","q":"Why does eating spicy food make you sweat even in a cold room?"},{"id":"sweet-potato-not-potato","t":"food","q":"Why isn't a sweet potato actually related to a potato at all?"},{"id":"sweetcorn-sugary-mutation","t":"food","q":"Why is the corn on the cob you eat fresh so much sweeter than dried corn?"},{"id":"syrup-thick-slow","t":"food","q":"Why is syrup thick and slow-pouring instead of runny like sugar water?"},{"id":"tempering-crystals","t":"food","q":"Why does cocoa butter need to set as one exact kind of crystal out of six possible kinds?"},{"id":"theobromine-lift","t":"food","q":"Why does eating chocolate give you a gentle lift, a bit like tea does?"},{"id":"toast-smell","t":"food","q":"Why does toast smell so good?"},{"id":"toffee-shatters-fudge-soft","t":"food","q":"Why does hard-crack toffee shatter like glass while fudge stays soft and creamy?"},{"id":"tomato-fruit","t":"food","q":"Why is a tomato a fruit and not a vegetable?"},{"id":"trawling-net-seafloor","t":"food","q":"Why do some fishing boats drag huge nets along the sea floor?"},{"id":"tropical-fruit-fridge-damage","t":"food","q":"Why should you never put a mango or a banana in the fridge?"},{"id":"tropical-vs-temperate-frost","t":"food","q":"Why can't mangoes and bananas grow anywhere apples and pears do?"},{"id":"true-cinnamon-cassava","t":"food","q":"Why are two very different spices both sold as \"cinnamon\"?"},{"id":"turmeric-stains","t":"food","q":"Why does turmeric stain everything a deep yellow that won't wash out?"},{"id":"turnip-swede-hybrid","t":"food","q":"Why are turnips and swedes so often mixed up with each other?"},{"id":"uht-milk-shelf-stable","t":"food","q":"Why can long-life milk sit unrefrigerated on a shop shelf?"},{"id":"undercooked-chicken-danger","t":"food","q":"Why is undercooked chicken risky when rare beef steak often isn't?"},{"id":"use-by-date","t":"food","q":"Why does food have a date on it?"},{"id":"vanilla-fermented-pod","t":"food","q":"Why does a vanilla pod have to be cured for months before it smells like vanilla?"},{"id":"vanilla-hand-pollinated","t":"food","q":"Why must nearly every vanilla flower in the world be pollinated by hand?"},{"id":"veg-bitter","t":"food","q":"Why do kids hate vegetables?"},{"id":"warm-place-rise","t":"food","q":"Why do you put bread dough somewhere warm to rise?"},{"id":"wasabi-fades-fast","t":"food","q":"Why does grated wasabi lose its punch within minutes?"},{"id":"wasabi-horseradish-enzyme","t":"food","q":"Why do wasabi and horseradish only turn hot after they're cut or crushed?"},{"id":"wasabi-real-rare","t":"food","q":"Why is most \"wasabi\" you eat not actually wasabi?"},{"id":"watermelon-water","t":"food","q":"Why is watermelon so full of water?"},{"id":"wheat-kernel-parts","t":"food","q":"Why does a single wheat grain contain three completely different parts?"},{"id":"whipped-cream-air","t":"food","q":"Why does cream turn fluffy when you whip it?"},{"id":"white-chocolate-barely","t":"food","q":"Why do some chocolate experts say white chocolate isn't really chocolate?"},{"id":"white-chocolate-taste","t":"food","q":"Why does white chocolate taste so different from dark, when both come from the same bean?"},{"id":"whitebait-eaten-whole","t":"food","q":"Why can you eat whitebait bones, head, eyes and all?"},{"id":"whole-vs-ground-spice","t":"food","q":"Why do whole spices stay fragrant for years while ground ones fade in months?"},{"id":"wholemeal-dense","t":"food","q":"Why does wholemeal bread rise less than white bread?"},{"id":"why-bacon-crispy-not-boiled","t":"food","q":"Why does bacon go crispy when it fries but stay soft if it's boiled?"},{"id":"why-chew","t":"food","q":"Why do we have to chew our food?"},{"id":"why-chicken-breast-white-legs-dark","t":"food","q":"Why is chicken breast meat pale but chicken leg meat dark?"},{"id":"why-chicken-skin-crispy","t":"food","q":"Why does chicken skin turn crispy in the oven but stay rubbery if it's steamed?"},{"id":"why-cured-meat-pink","t":"food","q":"Why does cured ham stay pink even after it's fully cooked?"},{"id":"why-different-cultures-different-meats","t":"food","q":"Why do different countries around the world eat such different meats?"},{"id":"why-duck-fatty-meat","t":"food","q":"Why is duck meat so much fattier than chicken?"},{"id":"why-fish-cooks-faster","t":"food","q":"Why does fish cook so much faster than beef or chicken?"},{"id":"why-fish-farmed-different-colour","t":"food","q":"Why is farmed salmon often a different colour from wild salmon?"},{"id":"why-fish-fillet-bones-different","t":"food","q":"Why do some fish have hundreds of tiny bones while others have almost none?"},{"id":"why-fish-skin-eaten","t":"food","q":"Why do some cooks recommend eating crispy fish skin instead of removing it?"},{"id":"why-freezing-preserves-meat","t":"food","q":"Why does freezing keep meat safe for months when the fridge only manages days?"},{"id":"why-halal-kosher-meat","t":"food","q":"Why do some families only eat meat prepared a certain way, like halal or kosher?"},{"id":"why-jerky-lasts","t":"food","q":"Why does dried meat like jerky last so long without going off?"},{"id":"why-lamb-mutton-different-names","t":"food","q":"Why is young sheep meat called lamb but older sheep meat called mutton?"},{"id":"why-lamb-taste-different","t":"food","q":"Why does lamb taste so different from beef, even cooked the same way?"},{"id":"why-lean-meat-dry-quick","t":"food","q":"Why does lean meat dry out faster than fattier meat when it's overcooked?"},{"id":"why-meat-age-flavour","t":"food","q":"Why do some steaks get 'aged' for weeks before they're sold?"},{"id":"why-meat-brine-juicy","t":"food","q":"Why do cooks soak meat like chicken or pork in salty water before cooking it?"},{"id":"why-meat-crackling-pork-skin","t":"food","q":"Why does pork crackling need to be scored and dried before roasting?"},{"id":"why-meat-glaze-sticky","t":"food","q":"Why does a sticky glaze caramelise onto meat instead of just running off?"},{"id":"why-meat-glue-schnitzel-thin","t":"food","q":"Why do cooks flatten meat thin for dishes like schnitzel?"},{"id":"why-meat-goes-grey-in-freezer","t":"food","q":"Why does meat sometimes get pale, dry patches after months in the freezer?"},{"id":"why-meat-goes-off-smell","t":"food","q":"Why does spoiled meat smell so bad?"},{"id":"why-meat-pink-inside-safe-pork","t":"food","q":"Why is it now considered safe to eat pork that's slightly pink in the middle?"},{"id":"why-meat-safe-temp-danger-zone","t":"food","q":"Why do cooks worry about meat sitting out at room temperature, even briefly?"},{"id":"why-meat-shrinks-cooking","t":"food","q":"Why does a piece of meat get smaller as it cooks?"},{"id":"why-meat-smoked-flavour","t":"food","q":"Why does smoking meat give it such a strong flavour?"},{"id":"why-meat-string-tie","t":"food","q":"Why do cooks tie a roast up with string before cooking it?"},{"id":"why-meat-substitutes-taste-similar","t":"food","q":"Why can some plant-based meat substitutes taste and even 'bleed' surprisingly like real meat?"},{"id":"why-meat-tenderiser-works","t":"food","q":"Why does bashing meat with a mallet make it more tender?"},{"id":"why-meat-thermometer-accurate","t":"food","q":"Why is a meat thermometer more reliable than cutting meat open to check it?"},{"id":"why-mince-different-cooking","t":"food","q":"Why does mince need to be cooked all the way through, even if the same cut as a steak doesn't?"},{"id":"why-organ-meat-different","t":"food","q":"Why does liver taste and cook so differently from muscle meat like steak?"},{"id":"why-sausage-casing","t":"food","q":"Why are sausages stuffed into a skin instead of just shaped by hand?"},{"id":"why-slow-cooker-tough-cuts","t":"food","q":"Why do slow cookers turn tough, cheap cuts of meat into something soft?"},{"id":"why-steak-cuts-differ","t":"food","q":"Why do different cuts of the same animal have such different names and prices?"},{"id":"why-vegetarians-dont-eat-meat","t":"food","q":"Why do some people choose not to eat meat at all?"},{"id":"windowpane-test","t":"food","q":"Why do bakers stretch dough to see through it before baking?"},{"id":"wood-fired-oven","t":"food","q":"Why does bread from a wood-fired oven taste different from home-oven bread?"},{"id":"yeast-alive","t":"food","q":"Why is yeast a living thing and not just a powder?"},{"id":"yew-poison-aril","t":"food","q":"Why is a yew berry's red flesh harmless but its seed deadly?"},{"id":"yoghurt-easier-lactose-intolerant","t":"food","q":"Why can some lactose-intolerant people manage yoghurt better than milk?"},{"id":"yoghurt-live-cultures","t":"food","q":"Why do some yoghurt tubs say they contain live cultures?"},{"id":"yoghurt-tangy-taste","t":"food","q":"Why does yoghurt taste tangy instead of sweet like milk?"},{"id":"yoghurt-thick-texture","t":"food","q":"Why is yoghurt thick when milk is runny?"},{"id":"zucchini-flower-sexes","t":"food","q":"Why does a zucchini plant grow two completely different kinds of flowers?"}]