Contents BUGS Why are slugs slimy And other curious questions about creepy-crawlies 6 Why do ants live together 8 Why do spiders make webs 10 Why do flies like poop 12 Why do centipedes have so many legs 14 Why do bees make honey 16 Why do ladybugs have spots 18 Why does a caterpillar make a chrysalis 20 Why do worms live underground 22 Why are slugs slimy 24 Why do snails have shells 26 Why do mosquitoes bite 28 Why do fireflies glow 30 Why are praying mantises so hard to see 32 Why do stink bugs stink 34 Wow What’s that 36 PETS Why do cats purr And other curious questions about our animal friends 38 Why do dogs sniff each other’s bottoms 40 Why do cats purr 42 Why do cats and dogs have claws 44 Why do rabbits have big ears 46 Why do tortoises walk so slowly 48 Why are hamsters so noisy at night 50 Why are there so many kinds of dogs 52 Why do fish have gills 54 Why can’t animals talk to us 56 Why do some animals have whiskers 58 Why do cats lick their fur 60 Why do mice squeak 62 Why do gerbils chew cardboard 64 Why do horses need shoes 66 Wow What’s that 68 WILD ANIMALS Why do giraffes have long necks And other curious questions about cool creatures 70 Why do frogs croak 72 Why do sharks have so many teeth 74 Why do crocodiles have bumpy skin 76 Why do octopuses have suckers on their arms 78 Why do elephants have trunks 80 Why do kangaroos have pouches 82 Why do birds make nests 84 Why do gorillas beat their chests 86 Why do snakes flick their tongues 88 Why are flamingos pink and orange 90 Why do squirrels bury nuts 92 Why do owls have big eyes 94 Why do giraffes have long necks 96 Why can’t penguins fly 98 Wow What’s that 100 THE BODY Why does music make me want to dance And other curious questions about the human body 102 Why do I yawn 104 Why does my mouth water 106 Why do I have wobbly teeth 108 Why do some of us wear glasses 110 Why do some things make me cry 112 Why do I dream 114 Why do I have eyelashes 116 Why is skin different colors 118 Why do I need to brush my teeth 120 Why does music make me want to dance 122 Why does my tummy rumble 124 Why do I get hiccups 126 Why do some people have curly hair and others have straight hair 128 Why do I have nails 130 Wow What’s that 132
Why does fruit have seeds 136 Why do I like sweet things 138 Why does old food get moldy 140 Why does chocolate melt 142 Why does chopping onions make me cry 144 Why are some cheeses stinky 146 Why are chili peppers spicy 148 Why does popcorn pop 150 Why do beets grow underground 152 Why do cakes puff up in the oven 154 Why does ice cream sometimes give me a headache 156 Why does Jell-O jiggle 158 Why do bananas turn brown 160 Why are raisins wrinkly 162 Wow What’s that 164 FOOD Why do cakes puff up in the oven And other curious questions about things we eat 134 HOW STUFF WORKS Why do trains run on tracks And other curious questions about machines and inventions 166 EARTH Why are flowers colorful And other curious questions about our planet 198 Why are rockets pointy 168 Why are helicopters so loud 170 Why do cars have horns 172 Why do trains run on tracks 174 Why do buildings have elevators 176 Why can I see myself in a mirror 178 Why don’t skyscrapers fall over 180 Why does a garbage truck smash the trash 182 Why do batteries run out 184 Why do airplanes make trails in the sky 186 Why do we flush the toilet 188 Why does my rubber duck float 190 Why do we have traffic lights 192 Why do ice skates have blades 194 Wow What’s that 196 Why do earthquakes happen 200 Why do volcanoes erupt 202 Why does the ocean have waves 204 Why can’t I meet a T rex 206 Why are flowers colorful 208 Why do rainbows appear after a rainstorm 210 Why is the sky blue 212 Why does it rain 214 Why are mountains so tall 216 Why are beaches sandy or pebbly 218 Why do leaves fall off some trees 220 Why do some rocks have crystals inside 222 Why are clouds different shapes 224 Why are deserts dry 226 Wow What’s that 228 SPACE Why do astronauts wear suits And other curious questions about the cosmos 230 Why can we only see stars at night 232 Why do stars twinkle 234 Why is it dark in space 236 Why does the sun shine 238 Why are planets round 240 Why is Mars red 242 Why does Saturn have rings 244 Why is Neptune blue 246 Why do we have night and day 248 Why does the moon change shape 250 Why does an eclipse happen 252 Why do astronauts wear suits 254 Why don’t we visit other planets 256 Why do we send animals to space 258 Wow What’s that 260 Glossary 262 Index 264 Source notes 266 Picture credits 269 Meet the WHY team 270 Wow What’s that answers 271
BUGS Why are slugs slimy And other curious questions about creepy-crawlies
