Topic
Animal questions for kids
Here are 476 questions about animals from 22 A Million Whys books, each with a short video answer. Book 11, The Animal Expedition is all about animals, and the rest come from other books in the series. Tap any question to watch the video and read the answer.
From Book 11: The Animal Expedition (150)
Why Do Mammals Have Fur or Hair?
Mammals have fur or hair because it works like a built-in blanket! Hair traps a layer of air next to the skin, which keeps body heat in.
Why Do Birds Have Feathers Instead of Fur?
Birds have feathers because feathers can do jobs that fur cannot! They are light and strong, and they are shaped for flying, staying warm, and keeping dry.
What Are Reptile Scales Made Of?
Reptile scales are made of keratin, the same tough stuff as your fingernails! The scales are thin, hard plates that cover the whole body like a suit of armor.
Why Do Some Animals Shed Their Coats?
Many animals shed or molt because they need to swap an old coat for a new one! Molting means dropping old fur or feathers so fresh ones can grow in.
Why Do Polar Bears Look White If Their Skin Is Black?
A polar bear looks white because its hairs scatter light, not because they are white! Each hair is clear and has no color of its own.
Why Do Peacocks Have Such Fancy Feathers?
A peacock's fancy train is a signal to peahens! A healthy male can grow a bigger, brighter train, so it tells her, I am strong.
Why Do Pangolins Roll Into a Ball?
A pangolin rolls into a ball because its scales turn it into armor! When a predator comes near, it curls up tight and tucks its tail over its face.
Why Do Frogs Feel Slimy?
Frogs feel slimy because their skin is covered in a thin layer of mucus! The slime keeps the skin moist, and a frog can even take in some air through wet skin.
Why Do Armadillos Wear Armor?
An armadillo wears armor because it gives the animal a shield on its back! Bony plates covered with tough skin protect its back, head, and tail.
Why Do Lions Have Manes?
Male lions have manes because a mane protects and shows off! A thick mane cushions the neck and head during fights with rivals.
Why Do Cats’ Fur Stand Up When They’re Scared?
A scared cat's fur stands up to make the cat look bigger! Tiny muscles at the base of each hair pull the hair upright.
Why Can’t a Turtle Crawl Out of Its Shell?
A turtle can't crawl out of its shell because the shell is part of its skeleton! The top shell is joined to the backbone and ribs, and the bottom shell is part of the skeleton too.
Why Do Elephants Have Almost No Fur?
Elephants have almost no fur because they are huge and live in hot places! A big body makes heat and loses it slowly.
Why Do Sloths Have Green Fur?
A sloth looks green because tiny green algae grow in its fur! Its hairs have small grooves, and the rain keeps them damp.
Why Are Blue Jays Blue Without Any Blue Color in Their Feathers?
A blue jay is blue because of how its feathers bounce light, not because of blue paint! Tiny structures inside each feather reflect blue light back to your eyes.
Why Do Lizards Drop Their Tails?
Many lizards drop their tails on purpose to escape! The tail breaks off at a weak spot, and the piece keeps wiggling for a while.
Why Do Worms Not Have Fur, Feathers, or Scales?
Worms have no fur, feathers, or scales because they breathe through their skin! An earthworm's skin has to stay thin and moist so air can pass through.
Why Do Penguins Have Dense Feathers?
Penguins have dense feathers to stay warm and dry in icy water! Their short, stiff feathers are packed tightly, with fluffy ones underneath.
Why Do Hippos Ooze a Red-Orange “Sweat”?
A hippo's red-orange ooze is not blood and not sweat! The thick liquid has special colored chemicals in it that work like a natural lotion and help block the Sun's rays.
Why Do Some Animals Change Color with the Seasons?
Some animals change color with the seasons to hide! Arctic foxes, snowshoe hares, and ptarmigans grow white coats or feathers for winter.
Why Do Rhinos Have Thick Skin Folds?
Rhinos have thick skin folds to protect their big bodies! The thick skin guards against thorny bushes, sunburn, and biting insects.
Why Do Bees Look Fuzzy?
Bees look fuzzy because their bodies are covered in branched hairs! The hairs help bees collect and carry pollen from flower to flower.
Why Does Shark Skin Feel Like Sandpaper?
Shark skin feels like sandpaper because it is covered in tiny tooth-shaped scales! These little scales are called denticles.
Why Do Birds Fluff Up Their Feathers When It Is Cold?
Birds fluff up their feathers in the cold to trap warm air! Still air is a great insulator, just like the filling in a puffy winter jacket.
Why Do Animals Need Skin Care From Nature?
Animals take care of their skin, fur, and feathers in many clever ways! Birds roll in dust or preen their feathers with oil.
Why Do Dogs Smell So Much Better than Humans?
Dogs smell so much better than people because they have far more scent sensors! A dog has about 300 million of them in its nose, and a person has about 6 million.
How Do Pit Vipers Sense Heat?
Pit vipers sense heat with two small pits on their faces! Each pit sits between an eye and a nostril.
Why Do Butterflies Taste with Their Feet?
Butterflies taste with their feet because they need to pick the right leaf! Taste sensors on the feet tell a butterfly if a plant is food for its caterpillars.
Why Do Snakes Flick Their Tongues?
Snakes flick their tongues to smell the world! A snake's tongue collects tiny scent particles from the air and ground, and the snake then checks them with a special spot in its mouth.
Why Do Chameleons’ Eyes Move Separately?
A chameleon can move each eye separately, so it can look in two directions at once! Each eye moves like its own little camera.
Why Are Some Owls’ Ears at Different Heights?
Some owls have ears at different heights to help them find sounds in the dark! A sound from above reaches one ear a tiny bit before the other.
Why Do Elephants Hear with Their Feet?
Elephants can pick up faraway rumbles through their feet! Elephants make deep rumbles, and some are too low for people to hear.
How Do Fish Feel the Water Moving Around Them?
Fish feel water moving with a special line of sensors along their sides! It is called the lateral line.
Why Does the Star-Nosed Mole Have a Nose Shaped Like a Star?
A star-nosed mole has a star-shaped nose because the star is a super touch sensor! It has 22 pink tentacles covered in tiny touch sensors.
Why Can a Platypus Find Food with Its Eyes Closed?
A platypus can find food with its eyes closed because its bill senses tiny electric signals! When it dives, it closes its eyes, ears, and nostrils.
Why Do Cats Have Whiskers?
Cats have whiskers because whiskers are super-sensitive feelers! They are long, stiff hairs rooted deep in the skin with many nerves.
Why Do Some Moths Have Feathery Antennae?
Male moths often have feathery antennae to catch scents in the air! The tiny branches give the antenna lots of surface for catching scent molecules.
Why Do Deer Flash White Tails?
A white-tailed deer flashes its tail to send a warning! When danger is near, it raises its tail and shows the bright white underside.
How Do Homing Pigeons Find Their Way Home?
Homing pigeons use several clues to find their way home! They can sense Earth's magnetic field, and they use the Sun's position.
Why Do Rattlesnakes Rattle?
A rattlesnake rattles to warn animals and people to stay back! It shakes the end of its tail, which is made of loose rings of keratin, and the buzzing sound says, I'm here.
How Do Mosquitoes Find People?
Female mosquitoes find people by following several clues at once! They sense the carbon dioxide in our breath from far away.
Why Do Rabbits Thump the Ground?
Rabbits thump the ground to warn each other! A rabbit stamps its strong back feet to make a loud thump.
How Do Spiders Feel a Bug Land in Their Web?
A spider's web is also a sensor! When an insect lands, the threads shake, and the spider feels the shaking and knows something is there.
Why Do Goats Have Rectangular Pupils?
Goats have rectangular pupils to see a wide view of the ground! The pupils are horizontal slots, not round circles like ours.
Why Do Sharks Sense Tiny Electric Twitches?
Sharks sense tiny electric signals with special pores near their snouts! All animals give off very weak electricity when their muscles move.
Why Do Prairie Dogs “Speak” in Chirps?
Prairie dogs chirp because their calls carry information about danger! They have different calls for different dangers.
Why Do Octopuses Taste with Their Arms?
Octopuses taste with their arms because their suckers have taste sensors! Each sucker has taste and touch sensors.
Why Do Meerkats Take Turns as Lookouts?
Meerkats take turns as lookouts so the whole group can stay safe! One meerkat, called the sentinel, stands on a high spot and watches for danger.
Why Do Catfish Taste with Their Whole Bodies?
Catfish taste with their whole bodies because taste sensors cover their skin! They also have extra ones on their whiskers, called barbels.
Why Can’t Snakes Blink?
Snakes can't blink because they have no movable eyelids! Instead, each eye is covered by a clear scale.
Why Do Wolves Live in Packs?
Wolves live in packs because a pack is really a family, and families can do big jobs together! A pack is usually a mother, a father, and their young.
Why Do Baby Ducklings Follow Their Mother in a Line?
Baby ducklings follow their mother in a line because they learn to follow the first big moving thing they see! That is usually their mom, and following her keeps them safe.
Why Do Elephants Follow a Matriarch?
Elephants follow a matriarch because she is the wise old leader of the herd! A matriarch is an older female who remembers where to find food and water.
Why Does a Beehive Have Just One Queen?
A beehive has just one queen because she is the egg layer for the whole hive! She lays almost all of the eggs, and her scent keeps the hive calm.
How Do Lionesses Hunt as a Team?
Lionesses hunt as a team because working together works better than going alone! Each lioness plays a different role in the hunt.
Why Do Orcas Teach Calves to Hunt?
Orcas teach their calves to hunt because hunting is a skill that has to be learned! Young orcas learn by watching their families, and each family has its own traditions.
How Do Ant Colonies Divide Up the Work?
Ant colonies divide up the work because each ant has a job, like in a tiny city! The queen lays eggs, and the workers do almost everything else.
Why Do Birds Nest in Colonies?
Birds nest in colonies because there is safety in numbers! In a big group, many eyes can spot danger and give the alarm.
Why Do Beaver Families Build Together?
Beaver families build together because the work is big, and every beaver can help! Kits learn from their parents and older brothers and sisters.
Why Do Kangaroo Joeys Stay in Pouches?
Kangaroo joeys stay in their pouches because they are born so tiny! The pouch is a warm, safe nursery that goes wherever mom goes.
Why Do Seahorse Dads Carry the Babies?
Seahorse dads carry the babies because they have a special belly pouch for the eggs! That makes seahorses one of the very few animals where dads are the ones who carry the young.
Why Do African Wild Dogs Vote with Sneezes?
African wild dogs vote with sneezes, which is a quiet way to decide when to go hunting! Before a hunt, the pack gathers for a greeting.
Why Do Swans Mate for Long Partnerships?
Swans often stay with the same partner for many years, because a good team makes a good family! Having a partner helps them guard the nest and raise their cygnets.
Why Do Squirrels Sometimes Raise Orphans?
Squirrels sometimes raise orphans because relatives can help each other out! Squirrels usually care for their own young, but sometimes a mother adopts babies that have lost their mother.
Why Do Zebras and Wildebeest Travel Together?
Zebras and wildebeest travel together because they make a great team! Each one is good at something different.
Why Do Naked Mole Rats Share Tunnels?
Naked mole rats share tunnels because they live in big underground colonies, a bit like ants! One queen has the babies, and everyone else has a job.
Why Do Starlings Fly in Giant Swirling Clouds?
Starlings fly in giant swirling clouds because each bird copies its closest neighbors! There is no leader at all.
Why Do Baby Birds Open Their Mouths So Wide?
Baby birds open their mouths so wide because it is a signal that says, Feed me! A big, wide beak is easy for parents to see and aim at.
Why Do Orangutan Moms Stay with Young So Long?
Orangutan moms stay with their young for so long because there is a lot to learn! Orangutans live in the treetops, and life up there is complicated.
Why Do Dolphins Babysit Each Other’s Calves?
Dolphins babysit each other's calves because it takes a team to raise little ones! In some groups, adults watch the calves while the mothers go hunting.
Why Do Leafcutter Ants Farm Fungus?
Leafcutter ants farm fungus because the fungus is their food! The ants cut up leaves, but they don't eat the leaves.
Why Do Wolves Bring Food to Den Pups?
Wolves bring food to the den pups because the pups are too little to travel far! The pack brings meals home to them.
Why Do Emperor Penguin Dads Hold Eggs?
Emperor penguin dads hold the eggs because the moms need to go to sea to eat! Dad keeps the egg warm through the freezing Antarctic winter.
Why Do Crows Remember Human Faces?
Crows remember human faces because they have very good memories! Studies show that crows can remember individual people for years.
Why Do Animal “Families” Sometimes Include Friends?
Animal families sometimes include friends because not everyone in a group is related! Some animals live with unrelated friends who help them.
How Do Jumping Spiders Hunt Without a Web?
Jumping spiders hunt without a web because they have amazing eyesight and a super pounce! They don't wait for dinner to get stuck.
Why Do Cheetahs Have Tear-Mark Lines?
Cheetahs have tear-mark lines because those dark stripes may work like sunglasses! The lines run from the inside corner of each eye down to the mouth.
Why Do Pelicans Scoop Fish with Their Big Bills?
Pelicans scoop fish with their big bills because the pouch works like a built-in net! It stretches wide and holds lots of water and fish.
Why Do Anglerfish Use Glowing Lures?
Anglerfish use glowing lures because the deep ocean is completely dark! The lure is a fishing rod with a glowing tip.
Why Do Venomous Snakes Have Venom?
Venomous snakes have venom because it helps them catch food and stay safe! Venom is a special kind of saliva with strong chemicals.
Why Do Bombardier Beetles Spray Hot Liquid?
Bombardier beetles spray a hot, smelly liquid as a super defense! The spray surprises and scares off hungry ants and frogs, and the beetle makes it with a clever chemistry trick inside its body.
Why Do Octopuses Squirt Ink?
Octopuses squirt ink because it helps them escape when they are scared! The dark cloud is a decoy, and it gives the octopus time to get away.
Why Do Some Caterpillars Look Like Snakes?
Some caterpillars look like snakes because it helps scare away hungry birds! Big spots on their heads look like snake eyes.
Why Do Honeyguide Birds Lead People to Honey?
Honeyguide birds in Africa lead people to honey because both of them get a treat! The bird knows where wild bees' nests are, and people can open them.
Why Do Oxpeckers Ride on Rhinos?
Oxpeckers ride on rhinos and other big animals to eat ticks and other bugs off their skin! The rhino gets cleaned, and the bird gets a meal.
Why Do Arctic Foxes Follow Polar Bears?
Arctic foxes follow polar bears because the bears leave tasty scraps behind! In winter, food is hard to find in the Arctic.
Why Do Antlions Dig Tiny Pits in the Sand?
Antlions dig tiny pits in the sand because the pits are sneaky traps for ants! The sand is so loose that the sides slide away.
Why Do Frogs Use Sticky Tongues?
Frogs use sticky tongues because they are the perfect bug catchers! A frog's tongue is soft, quick, and covered in sticky saliva.
Why Do Eagles Have Talons?
Eagles have talons because those strong, curved claws are perfect for catching food! An eagle's feet work like a pair of powerful hands.
Why Do Gazelles Stot (Pronk) When Fleeing?
Gazelles stot, or pronk, when fleeing because it is a message to the hunter! The bouncy jumps say, I'm healthy and fast, so don't waste your time.
Why Are Dragonflies Such Good Hunters?
Dragonflies are such good hunters because they have big eyes, smart brains, and amazing wings! They catch their prey around 9 times out of 10.
Why Do Leaf-Tailed Geckos Look Like Dead Leaves?
Leaf-tailed geckos look like dead leaves because it helps them hide! They live in the forests of Madagascar.
Why Do Remora Fish Stick to Sharks?
Remora fish stick to sharks because they get a free ride and a free meal! A remora has a flat sucker on top of its head.
Why Do Vampire Bats Share Blood Meals?
Vampire bats share food because sharing keeps the whole roost safe! A bat that cannot find a meal for two nights might get very sick.
Do Birds Really Clean Crocodile Teeth?
Scientists have almost never seen birds clean crocodile teeth, so the story is mostly a legend! Wild crocodiles are dangerous, so people should always watch them from far away.
Why Do Sea Otters Use Rocks as Tools?
Sea otters use rocks as tools because it helps them open hard-shelled food! They eat shellfish like clams and crabs.
Why Do Army Ants Swarm?
Army ants swarm because together they can do what one ant never could! They march in huge groups through the forest.
Why Do Cuttlefish Hypnotize Crabs with Color Waves?
Cuttlefish make color waves because the moving patterns can distract a crab! Bands of dark and light ripple across their skin.
Why Do Poison Dart Frogs Advertise Bright Colors?
Poison dart frogs advertise bright colors because the colors are a warning sign! They say, I taste bad, or I'm toxic, and predators learn to stay away.
Why Do Some Animals Help Raise Other Species’ Young (Brood Parasitism)?
Some animals help raise other species' young because they get tricked! Cuckoos and cowbirds lay their eggs in other birds' nests.
Why Do Weaverbirds Weave Hanging Nests?
Weaverbirds weave hanging nests because a nest swinging from a thin branch is hard for snakes to reach! The male builds it using only his beak and feet.
Why Do Birds Choose Different Nest Materials?
Birds choose different nest materials because each material does a different job! They use what they can find nearby that keeps eggs safe and snug.
Why Do Termites Build Tall Mounds?
Termites build tall mounds because the mounds work like a natural air conditioner! Inside is a maze of tunnels and chimneys.
Why Do Burrowing Owls Live Underground?
Burrowing owls live underground because it keeps them cool, warm, and safe! They live on grassy prairies where there are very few trees.
Why Do Tailorbirds Sew Leaves Into Nests?
Tailorbirds sew leaves into nests so their eggs stay hidden and dry! They live in warm parts of Asia.
Why Do Polar Bears Dig Snow Dens?
Polar bears dig snow dens because snow is a great blanket for newborn cubs! Mother bears dig the dens in big snowdrifts, and outside it may be freezing while inside stays much warmer.
Why Do Foxes Dig Dens with More than One Door?
Foxes dig dens with more than one door so they always have a way out! A backup exit keeps the fox and her kits safe.
Why Do Wasps Make Paper Nests?
Wasps make paper nests because paper is light, strong, and made from things they find! They make the paper themselves.
Why Do Swallows Build Nests Out of Mud?
Swallows build nests out of mud because mud dries hard and sticks to walls! That gives them a strong little cup to raise their chicks.
Why Do Squirrels Build Leafy Nests High in Trees?
Squirrels build leafy nests high in trees to stay warm, dry, and out of reach! These round nests are called dreys.
Why Do Moles Dig Such Long Tunnels?
Moles dig long tunnels because the tunnels are both their home and their hunting ground! Worms and insects wander into the tunnels.
Why Do Eagles Reuse Nests for Years?
Eagles reuse nests for years because rebuilding takes huge effort! A good nest in a good spot is worth keeping.
Why Do Land Snails Seal Their Shell Doors?
Land snails seal their shell doors to keep from drying out! When the weather turns dry or cold, they pull back inside.
Why Do Bats Roost in Caves?
Bats roost in caves because caves are dark, cool, and steady all year! That makes a safe place to sleep during the day.
Why Do Spiders Choose Corners and Doorways?
Spiders choose corners and doorways because that is where insects are likely to pass! A good spot means more food.
Why Do Ghost Crabs Dig Burrows on the Beach?
Ghost crabs dig burrows on the beach to stay cool, damp, and hidden! The hot sun can dry a crab out.
Why Do Flamingos Stand in Shallow Lakes?
Flamingos stand in shallow lakes because that is where their food is! They filter tiny shrimp and algae from the water.
Why Do Urban Foxes Live in Cities?
Urban foxes live in cities because cities offer food, shelter, and quiet spots! Red foxes are adaptable, which means they can adjust to new places, and many live in towns across Canada.
Why Do Migratory Birds Need Stopover Wetlands?
Migratory birds need stopover wetlands because they cannot fly the whole trip without a break! Wetlands are full of food, like insects and seeds.
Why Do Coral Reef Fish Stay Near Home Ranges?
Coral reef fish stay near home because knowing a place well helps them survive! They learn where food is and where to hide.
Why Do Bees Build Honeycomb Out of Six-Sided Cells?
Bees build honeycomb out of six-sided cells because hexagons are the perfect shape! They fit together with no gaps.
Why Do Trapdoor Spiders Live in Burrows with Lids?
Trapdoor spiders live in burrows with lids because the lid hides them and keeps the burrow moist! The spider waits in the shadows.
Why Do Woodpeckers Carve Nest Holes in Trees?
Woodpeckers carve nest holes in trees because a hole in a trunk is a safe, dry home! It keeps eggs away from most predators.
Why Do Tree Frogs Need Moist Micro-Homes?
Tree frogs need moist micro-homes because their thin skin dries out fast! A micro-home is a tiny damp hideout, like a leaf pocket or a hollow in a tree.
Why Do Animals Share Habitats Without Always Fighting?
Animals can share habitats without always fighting because they use different parts or times of it! That way they don't compete as much.
Why Is a Giraffe’s Neck So Long?
A giraffe's neck is so long because it helps the giraffe reach leaves high up in trees! Few other animals can eat up there, so the giraffe does not have to share.
Why Can Peregrine Falcons Dive So Fast?
Peregrine falcons can dive so fast because they use gravity and a perfect shape! They climb high first, then fold their wings.
Why Can a Mantis Shrimp Punch So Fast?
A mantis shrimp can punch so fast because its arm works like a spring-loaded hammer! The club is held back by a latch, then released.
Why Is a Cheetah the Land Sprint King?
A cheetah is the land sprint king because its body is built for speed! It can run up to about 100 kilometers an hour.
Why Can Archerfish Shoot Water at Bugs?
Archerfish can shoot water at bugs because they have a built-in squirt gun! They spit a strong jet of water at insects on leaves above.
Why Do Tardigrades Survive Extreme Conditions?
Tardigrades survive extreme conditions because they can dry up and pause their bodies! These tiny animals look like chubby bears with eight legs.
Why Can Some Animals Live for Hundreds of Years?
A few animals, like the Greenland shark and the ocean quahog clam, can live for hundreds of years! They live in cold water, where their bodies work slowly and age slowly.
Why Do Tiny Shrews Have to Eat Almost All Day?
Tiny shrews eat almost all day because their little bodies burn energy super fast! A shrew is one of the smallest mammals, with a pointy nose and tiny eyes.
Why Do Wood Frogs Freeze in Winter and Thaw?
Wood frogs freeze in winter and thaw in spring because sugars in their bodies work like antifreeze! Their hearts stop beating and ice forms around their cells, but they wake up again when it warms up.
Why Do Sperm Whales Dive So Deep?
Sperm whales dive so deep because their favorite food lives in the dark depths! They can dive over a thousand meters.
How Do Scientists Recognize Individual Animals From Their Spots and Stripes?
Scientists can recognize individual animals because many animals have patterns that are one of a kind! Spots, stripes, and scars work like fingerprints.
Why Do Wildlife Corridors Matter?
Wildlife corridors matter because roads split habitats into pieces! Animals that try to cross busy roads are in danger.
Why Do Rehab Centers Help Injured Animals?
Rehab centers help injured animals because wild animals need trained care! Wildlife rehabilitators look after hurt or orphaned wild animals and then release them back to the wild when they are better.
Why Should You Never “Rescue” a Fawn Alone?
You should never rescue a fawn alone because it is usually not abandoned! A mother deer often leaves her fawn hidden for hours while she feeds nearby.
Why Do Bird Windows Need Stickers?
Bird windows need stickers because birds cannot tell that glass is solid! Glass can reflect trees and sky, or look like an open path.
Why Do Bat Houses and Nest Boxes Help Wildlife?
Bat houses and nest boxes help wildlife because safe homes are getting harder to find! Old hollow trees are getting rarer.
Why Do Zoos Run Breeding Programs?
Zoos run breeding programs to help endangered animals survive! Zoos work together to keep track of each animal's family.
Why Do Citizen Scientists Count Butterflies?
Citizen scientists count butterflies to help real scientists learn! Citizen scientists are volunteers who collect information, and you can be one!
Why Do Quiet Zones Help Nesting Birds?
Quiet zones help nesting birds because noise and surprises can scare them off their nests! Birds nest on the ground or in shrubs.
Why Do Some Animals Sleep with Half Their Brain Awake?
Some animals sleep with half their brain awake so they can rest and stay safe at the same time! Dolphins and some birds can do this.
Why Do Researchers Use Camera Traps?
Researchers use camera traps to see animals that stay away from people! A camera trap takes a picture when it senses movement or warmth.
Why Is Habitat the Best “Rescue”?
Habitat is the best rescue because protecting a home helps many animals at once! Rescuing one injured animal helps just that one.
Why Can a Flea Jump So High?
A flea can jump so high because its legs have a tiny built-in spring! The spring is made of a rubbery protein called resilin.
Why Should Curiosity Stay Kind?
Curiosity should stay kind because wild animals need space to stay safe! Watching from a distance and never chasing or touching them helps animals and lets you learn more.
Why Do Scientists Still Discover New Animal Species Every Year?
Scientists still discover new animal species every year because Earth is huge and full of tiny, hidden animals! Most places have never been searched closely.
From Book 1: The Great Expedition (19)
Why Do Cats Purr? The Rumble in the Voice Box!
A cat's purr is a steady, soothing rumble, and it comes from the voice box, or larynx. Tiny muscles there vibrate quickly, and the purr happens as the cat breathes in and out.
Why Do Bees Dance? The Waggle Dance Explained!
Bees can share directions with a dance! When a scout bee finds flowers, she returns to the hive and dances a figure eight.
Why Don't Woodpeckers Get Headaches? A Built-In Helmet!
Woodpeckers can peck thousands of times a day and stay headache-free, and the page shows why. Their skulls are full of tiny spaces that cushion the brain like a natural...
Why Do Dogs Tilt Their Heads? Clues From a Curious Pup!
When your dog tilts its head, it may be trying to see and hear better. A long muzzle can get in the way of what is straight ahead, and a tilt moves it aside for a clearer view.
Why Are Flamingos Pink? It Starts With Their Dinner!
Flamingo chicks are not born pink, they start out fluffy and light grey. Flamingos eat shrimp and algae rich in carotenoids, which are natural pigments, and the pigment settles in their feathers to make them pink.
Why Do Chameleons Change Color? It's More Than Hiding!
Chameleons do not just change color to hide. Their skin has stacked layers, like a tiny living sandwich, and cells in the layers tilt and stretch like blinds on a window, changing which colors bounce back to our eyes.
Why Can Owls Turn Their Heads So Far?
Owls can look behind them without moving their bodies! Their tube-shaped eyes barely roll in their sockets, so they turn the whole head instead.
Why Do Sharks Have So Many Teeth? A Conveyor Belt of Chompers!
Sharks are tooth experts! Their teeth are tools that fall out when worn or loose, and behind the front teeth are backup rows waiting their turn, like a conveyor belt.
Why Do Whales Sing? Songs That Travel for Miles!
Whale songs are some of the ocean's most amazing sounds! Sound travels far in water, and the page says whale songs can travel for miles.
Why Do Penguins Huddle? Teamwork Keeps Them Warm!
Penguins have a clever plan for staying warm in the cold. Wind steals body heat, so they gather in a tight circle where the birds on the outside block the wind for the group.
Why Is Spider Silk So Strong? Spiders' Super Thread!
Spider silk starts out as a liquid protein inside the spider's gland. As it is pulled into a fiber, the protein molecules line up and lock together, making a strong thread.
Why Do Butterfly Wings Have Colors? Paint vs. Tiny Mirrors!
Butterfly colors come from two tricks. Some color is pigment, which is like nature's paint that soaks into things.
Why Do Camels Have Humps? It's Not What You Think!
Many people think a camel's hump holds water, but the page says it does not. The hump is a fat backpack, and keeping fat in one place helps the rest of the body dump heat in the hot desert.
Why Do Cows Have Four Stomach Rooms? A Tiny Teamwork Tummy!
A cow's stomach is a four-room digestion system! Grass is made of tough cellulose, so cows rely on billions of microbes in the rumen, the microbe kitchen, to break it down.
Why Can Snakes Swallow Big Prey? Jaws That Walk!
Snakes can swallow animals wider than their heads thanks to some super clever skull and jaw features. A snake's skull bones are loosely connected, so the head can...
Why Do Bats Use Sound to Hunt? Echoes in the Dark!
Night is hard to hunt in by eye, so bats use sound! They make high-pitched clicks with their mouth or nose, and the clicks bounce back as echoes.
Why Do Fireflies Light Up? A Cold, Glowing Code!
Fireflies make light right inside their bodies! Special chemicals called luciferin and luciferase mix with oxygen in the abdomen to create a glow.
Why Do Ants Follow a Trail? A Secret Scent Path!
When an ant finds food, she lays down a scent trail to tell her sisters. The other ants follow the pheromones, the chemical scent, straight to the food.
Why Do Zebras Have Stripes? Scientists Are Still Asking!
Scientists still argue about why zebras have stripes, and there is no single answer everyone agrees on yet. One idea is that stripes seem to confuse biting flies, which...
From Book 2: The Inside Expedition (1)
From Book 3: The Built Expedition (1)
From Book 4: The Wild Expedition (46)
Why Do Bees Make Honey?
Honey is bee food for winter. Flowers do not bloom all year, so a hive stores extra sugar as thick, long-lasting honey.
Why Do Mosquitoes Bite?
Not every mosquito bites people. Many sip plant juices, and only some females take a tiny blood meal, because they need extra protein to make eggs.
Why Do Spiders Spin Webs?
A web is a hunting net and a home alarm. Spider silk is liquid protein that hardens in air into a thread that is very strong for its size.
Why Do Ants Walk in a Line?
The line is a smell road. A finder ant lays a scent trail from food to the nest, so the rest of the team can follow without a map.
Why Do Fireflies Glow?
The glow is a living lantern, used as a signal. Many fireflies flash to find a mate, and some young larvae glow too, as a keep-away warning.
Why Do Butterflies Start as Caterpillars?
A butterfly is one animal with two jobs. The caterpillar is the eating machine, and the adult is the flying, mating, nectar-sipping machine.
Why Do Worms Come Out After Rain?
Wet ground fills the worm's tunnels with water. Worms breathe through damp skin, and coming up is often easier than staying in a flooded tube.
Why Do Crickets Chirp?
A chirp is a cricket song. Most of the night music you hear is a male, calling to a female, or warning other males away.
Why Can Ants Lift So Much?
An ant is small, but its muscles are thick for its size. On such a tiny body, that strength can move a crumb many times heavier than the ant.
Why Do Beetles Have Hard Shells?
Those shiny covers on a beetle are armor! They are the front wings, changed into a hard case.
Why Do Spiders Have Eight Legs?
Spiders are arachnids, not insects. The arachnid body plan comes with eight walking legs, while insects get six.
Why Do Bees Dance?
A honeybee dance is a map in motion! A finder bee tells the hive where good flowers are by walking a figure-eight on the honeycomb.
Why Do Birds Sing?
A bird song is a message! Many birds sing to claim a territory and to find a mate.
Why Do Squirrels Bury Nuts?
A buried nut is a winter pantry! Food is easy to find in fall, and scarce in snow.
Why Do Baby Deer Have Spots?
A fawn's spots are camouflage! Sun flecks on a forest floor look a lot like a spotted fawn.
Why Do Owls Fly So Quietly?
Silence is a hunting tool! An owl that whispers through the air can hear a mouse.
Why Do Woodpeckers Peck Trees?
Pecking is a toolkit! Woodpeckers drum to talk, chip holes to nest, and tap bark to find insect larvae hiding in the wood.
Why Do Frogs Croak After Rain?
Rain makes the world safer for frog eggs! Many male frogs croak after a storm to call females to fresh pools.
Why Do Snakes Shed Their Skin?
A snake wears its skin like a tight sock! The sock cannot grow, so shedding lets the snake get bigger and replaces worn scales.
Why Do Bats Fly at Night?
Night is an open shift for hunters! Many bats hunt moths and mosquitoes after the birds that hunt by sight have gone to roost.
Why Do Beavers Build Dams?
A dam makes a beaver pond! Deep, still water hides the lodge door from land hunters.
Why Do Ducks Have Webbed Feet?
Webbed feet are living paddles! The skin between the toes turns each kick into a bigger push through the water.
Why Do Turtles Hide in Shells?
A turtle's shell is its skeleton on the outside! The ribs and backbone are joined to that armor, so the turtle can never take its house off.
Why Do Geese Fly in a V?
A V is teamwork in the sky! Each bird rides a little lift from the swirl at the wingtip of the bird ahead.
Why Do Hummingbirds Hover?
Hovering lets a hummingbird drink from a flower that cannot hold its weight! The bird is a tiny helicopter with a straw.
Why Do Wolves Howl?
A howl is long-distance talk! Pack members can find each other, and claim a valley.
Why Do Deer Grow Antlers?
Antlers are a seasonal crown! Male deer grow them to show strength, and to spar with rivals in the fall breeding season.
Why Do Some Animals Play Dead?
Playing dead is a last trick! Some hunters want a chase.
Why Do Birds Migrate?
Migration is a food-and-weather trip! When insects and berries fade and the cold comes, many birds fly to places that still have meals.
Why Do Foxes Have Bushy Tails?
A fox tail is a tool kit! It is a winter blanket, a balance pole, and a signal flag, all in one fluffy wrap.
Why Do Some Animals Come Out Only at Night?
Night is a different work shift! When the air is cooler, there are fewer daytime hunters around, and there's a buffet of moths and mice.
Why Do Frogs Start as Tadpoles?
A tadpole is a frog's water-baby shape! Frog eggs are laid in water, so the first body is built for swimming and eating pond food.
Why Do Ducks' Feathers Shed Water?
Duck feathers overlap like shingles on a roof! A duck also gets a thin coat of oil from a gland near its tail, so water beads up and rolls off instead of soaking in.
Why Do Some Fish Swim in Schools?
A school is a moving crowd of fish! Many eyes spot danger, and the group can twist together, so a hunter has a harder time picking just one fish.
Why Do Mosquitoes Hatch Near Water?
Mosquito babies are aquatic! Eggs are laid on still water.
Why Do Turtles Bask on Logs?
Turtles are cold-blooded, so they use the sun as a heater. Water steals heat, but air and sunshine give it back.
Why Do Beavers Build Dams? Nature's Engineers
A dam is a beaver's tool for making deep, still water. Beavers are nature's engineers.
Why Do Frogs Croak After Rain? The Pond Chorus
Rain makes travel and breeding easier for frogs. Wet ground does not dry out their skin, and puddles and ponds fill up.
Why Do Ducks Dabble Upside Down?
Dabbling is shallow-water grocery shopping. A duck tips its tail up and its head down to reach food on the bottom.
Why Do Fireflies Light Up?
A firefly's glow is a chemical lantern in its belly. A special reaction makes cold light with almost no heat.
Why Do Owls Fly So Quietly? Think Like the Mouse
An owl hunts mostly by listening, and a mouse has sharp ears too. If the owl's wings were loud, the mouse would hear a warning and run away, so owls are built to hush the air.
Why Do Bats Zip Around at Dusk?
Dusk is insect rush hour. Many bats are night fliers that hunt with sound, and they zip where mosquitoes and moths rise.
Why Do Some Animals See Well at Night?
Night hunters pack extra tools into their eyes. A wide pupil lets in more light, and special cells called rods catch dim light.
Why Do Night Insects Sound Like a Band?
Crickets, katydids, and some frogs all clock in as night singers. Each species has its own instrument and its own pattern and tempo.
Why Do Crickets Chirp After Sunset?
A male cricket rubs a file on one wing against a scraper on the other wing to make a chirp. The chirp is a night advertisement that says, I am here, and I am your kind.
Why Do Deer Freeze in Headlights?
A sudden blast of bright light can overwhelm a night-adapted eye. It is like a noon sun switched on in one second.
From Book 5: The Time Expedition (4)
The Big Goodbye! Why Did Non-Bird Dinosaurs Disappear?
About 66 million years ago, a huge space rock hit Earth, and big volcanic eruptions were happening around the same time. Earth's climate changed, and the dinosaurs that were not birds died out.
Tooth Talk! How Can a Tooth Tell What an Animal Ate?
Teeth come in different shapes for different foods. Sharp, pointed teeth are good for tearing meat, while flat teeth are good for grinding plants.
Follow the Herd! Why Did People Follow Animal Herds?
Animals like deer and bison moved from place to place to find fresh food. People who depended on hunting often moved along with them.
Best Friends Forever! Why Did People Domesticate Dogs?
Dogs are descended from wolves, and they were probably the first animals people tamed. Over a very long time, some wolves that lived near people became friendlier and started to help.
From Book 6: The Ocean Expedition (42)
Why Do Birds Follow the Tide Line?
When the water falls, it uncovers snacks like worms, tiny clams, and leftover bits. Birds walk the wet stripe like a moving buffet.
Why Do Fish Have Gills?
Fish pull oxygen out of the water with thin gill tissues. We air-breathers use lungs instead.
Why Don't Fish Drown?
Drowning happens when lungs fill with water, and fish do not use lungs. They use gills, which are built to pull oxygen out of water.
Why Do Fish Have Scales?
Scales are thin plates that cover a fish's body. They protect the fish and help it slip through the water.
Why Do Some Fish Swim in Schools?
Many eyes spot danger faster. A swirling crowd makes it hard for a hunter to pick one fish.
Why Are Fish Slippery?
Fish make a thin coat of slime called mucus. It helps them glide through water.
Why Can Some Fish Glow?
Some deep-sea fish make light inside their bodies with a chemical reaction. Others host glowing bacteria that live on them.
Why Does an Octopus Have Three Hearts?
An octopus is a mollusk, not a fish, and it has three hearts. Two hearts serve the gills, and a third heart serves the rest of the body.
Why Can an Octopus Change Color?
An octopus can match rock, sand, or coral in a blink. Tiny color cells in its skin open and close.
Why Do Crabs Walk Sideways?
A crab's legs fold out from the sides of its body. Its joints swing left and right more easily than front and back.
Why Does a Hermit Crab Wear a Shell?
A hermit crab's back end is soft. It slides into an empty snail shell and carries the house along.
Why Do Jellyfish Sting?
A jellyfish has no claws and no teeth. Its tentacles are covered in tiny stinging cells.
Why Isn't a Jellyfish a Fish?
A fish has a backbone, gills, and usually scales. A jellyfish has none of those!
Why Do Some Fish Have Whiskers?
Some fish, like catfish, have whisker-like feelers near the mouth. They are called barbels.
Why Do Flying Fish Jump?
A flying fish shoots out of the water and spreads its long, stiff fins like wings. It does not flap like a bird.
Why Does an Eel Look Like a Snake?
An eel is a long fish. A snake is a long reptile.
Why Do Some Fish Live in the Dark?
Sunlight fades as you go deeper in the ocean. In the deep sea, it is dark all day and all night.
Why Do Whales Breathe Air?
A whale looks like a fish, but it is a mammal, like you. That means it has lungs, not gills, and it must come up to breathe air.
Why Do Whales Have a Blowhole?
A blowhole is a whale's nose, but it sits on top of the head. Long, long ago, whale ancestors had nostrils on their snouts.
Why Do Some Whales Sing?
Some whales, especially male humpbacks, make long, patterned sounds called songs. Songs may help whales find a mate, or keep in touch across the sea.
Why Do Whales Travel So Far?
Many whales make long trips each year, called migrations. They feed in cold, food-rich water, and then swim to warm water to have their babies.
Why Is a Blue Whale So Huge?
The blue whale is the largest animal that has ever lived. Ocean water holds up its body, so it does not have to carry all that weight like a land animal would.
Why Do Some Whales Have Baleen Instead of Teeth?
Some whales have no teeth. Instead, they have baleen, a row of tough, fringed plates hanging from the upper jaw.
Why Do Sharks Have So Many Teeth?
A shark's teeth grow in rows. When a front tooth falls out, a new one from the row behind moves up to take its place.
Why Do Many Sharks Keep Swimming?
Sharks breathe with gills, and gills need fresh water flowing over them. Many open-water sharks swim with their mouths slightly open, so water streams in all the time.
Why Do Some Sharks Look Like Carpets?
Carpet sharks, such as wobbegongs, have blotchy, patterned skin and little tassels around the mouth. That makes them look just like the reef floor.
Why Don't Most Sharks Hunt People?
Sharks hunt fish, seals, and other ocean animals. A person has a strange, bony shape and is not what sharks normally eat.
Why Can a Shark Smell a Tiny Bit of Blood?
A shark's nose is a pair of pits on its snout. Water flows in, and tiny sensors inside pick up smells.
Why Is a Whale Shark Not a Whale?
A whale shark is the biggest fish in the sea. It is a shark, not a whale.
Why Do Seals Climb Onto Rocks?
Seals hunt in the water, but they are mammals, so they need to rest on land. They climb onto rocks or sand to rest, warm up, dry off, and have pups.
Why Do Sea Turtles Come Back to a Beach?
Sea turtles often return to nest on the same stretch of coast where they hatched, even decades later. A mix of smell, Earth's magnetic field, and wave clues helps guide them home.
Why Do Whales Have Blubber?
Blubber is a thick layer of fat under a whale's skin. It does three jobs: it keeps heat in, it stores energy, and it helps the whale float.
Why Do Whales Leap Out of the Water?
When a whale launches most of its body out of the water, that is called a breach. Scientists think a breach can send a message, knock off hitchhikers, or give the whale a look around.
Why Is a Manatee Called a Sea Cow?
A manatee is a gentle, slow mammal that grazes on seagrass and other water plants. People nicknamed it the sea cow, because its slow grazing looks like a cow in a field.
Why Is Coral an Animal, Not a Rock?
Coral looks like rock, but each tiny piece is an animal called a polyp, with a mouth and tentacles. The hard part is a limestone skeleton that the polyp builds around itself.
Why Do Parrotfish Poop Sand?
Parrotfish scrape algae off rocks and coral with a strong beak. They swallow bits of limestone along with it, and grinding teeth in their throats crush it into powder.
Why Do Cleaner Fish Pick at Bigger Fish?
Cleaner fish and cleaner shrimp eat pests and dead skin off bigger fish. The big fish gets cleaned, and the cleaner gets a meal.
Why Do Christmas-Tree Worms Vanish?
Those little colorful trees on a Christmas-tree worm are really its gills and feeding fans. The worm lives safely in a tube in the coral.
Why Do Sea Turtles Eat Bags?
Sea turtles eat jellyfish. A pale plastic bag floating in the water can look a lot like one.
Why Do Scientists Tag Fish and Turtles?
You can't follow a turtle across the ocean on a bike! So scientists use small tags and satellite packs, so animals can report where they feed, nest, and hide.
Why Is Dumping Aquarium Fish in the Sea a Bad Idea?
Aquarium fish, plants, and snails can survive and breed in places they don't belong. If they escape into the wild, they can crowd out the native animals.
Why Does Turning Off Extra Lights Help Hatchling Turtles?
Baby sea turtles hatch at night and crawl toward the brightest, lowest horizon, which is usually the sea. But street lights and porch lights can confuse them and pull them inland instead.
From Book 7: The Weather Expedition (3)
Why Do Clouds Sometimes Look Like Animals?
When you see a cloud shaped like a dragon, your brain is doing something clever. Brains love finding faces and animals in random shapes.
Why Do Birds Migrate with the Seasons?
Many birds migrate with the seasons to follow food and find safe weather for nesting. When winter makes insects and plants scarce, they travel to places with more food.
Why Do Bears and Other Animals Slow Down in Winter?
Bears and other animals slow down in winter because food is scarce and cold weather costs a lot of energy. Slowing the body down saves energy, so they can survive until spring.
From Book 9: The Food Expedition (3)
Why Are Chili Peppers Spicy for Mammals But Not Birds?
Chili peppers burn our mouths but not birds' beaks! The spicy chemical is called capsaicin, and mammals feel it as heat and pain.
Why Do Bees Matter for So Many Foods?
Bees matter for so many foods because they pollinate flowers! Pollination helps plants make fruits, seeds, and nuts.
Why Do Some Fish Need Cold Trucks More than Apples?
Fish need colder trucks than apples because seafood spoils much faster! Fish are rich in moist protein, and they can grow harmful bacteria quickly if warm.
From Book 12: The Volcano Expedition (4)
Why Do Animals Sometimes Act Odd Before Quakes?
People have noticed that pets and wildlife sometimes act strangely before a quake, but scientists have not found a reliable pattern. Animals may react to many things, so their behavior cannot be used to predict earthquakes.
What Lives in Hot Springs That Would Be Too Hot for Most Animals?
Tiny heat-loving microbes live in hot springs! They are called thermophiles, and they love water that would hurt most animals.
Why Do Strange Animals Live By Vents Without Sunlight?
Strange animals live at deep ocean vents, where sunlight can never reach! Tiny microbes there make food from chemicals in the hot water instead of from sunshine.
Why Do Pets and Farm Animals Need a Plan During an Eruption?
Pets and farm animals need a plan during an eruption because they cannot make plans on their own. Their families have to plan for them.
From Book 13: The Light Expedition (3)
Why Can a Flashlight and Your Hands Make a Shadow Animal?
A shadow forms where something blocks light. Your hands are the object, and the wall catches the shape.
Why Can Bees See Patterns on Flowers That We Cannot?
Bees and many other insects can see ultraviolet light, which humans cannot. Many flowers have patterns that only show up in ultraviolet.
Why Must You Never Shine a Laser Pointer at Anyone's Eyes, a Plane, or an Animal?
A laser pointer packs lots of light into a tiny spot, so it is a tool and not a toy! Never shine one at eyes, planes, or animals.
From Book 14: The Sound Expedition (5)
Why Can You Hear a Mosquito's Wings but Not a Slowly Flapping Bird's?
You hear a mosquito's wings because they beat hundreds of times each second! That is fast enough to make a tone your ears can hear.
Why Do Mosquitoes Whine High While Bumblebees Buzz Low?
Mosquitoes whine high and bumblebees buzz low because of how fast their wings flap! A mosquito flaps hundreds of times each second.
Why Can't We Hear a Dog Whistle?
We cannot hear a dog whistle because it makes sounds above 20,000 hertz! That is higher than humans can hear.
What Is Ultrasound, and How Do Bats and Doctors Use It?
Ultrasound is sound with a pitch so high that people cannot hear it! The waves are still real, and they travel through air, water, and the body.
Why Do Some Animals Have Giant Ears?
Some animals have giant ears because big ears catch faint sounds from far away! A bigger ear collects more sound waves, like a larger bucket collects more rain.
From Book 15: The Robot Expedition (3)
Why Do Some Robots Wriggle Like Snakes?
Snake robots wriggle because they bend in a wave that travels down their body! The wave pushes against the ground or walls and moves them forward.
Why Do Engineers Copy Animals When They Build Robots?
Engineers copy animals when they build robots because animals have been solving problems for millions of years! Nature has already tested many good designs.
Why Do Swarms of Tiny Robots Work Together Like Ants?
Swarms of tiny robots work together like ants because each one follows a few simple rules! Each robot senses only its neighbors.
From Book 16: The Desert Expedition (28)
Why Do Big Ears Help Some Desert Animals Cool Off?
Big ears have lots of tiny blood vessels near the surface! When warm blood flows through the thin skin, heat escapes into the air, and the blood returns cooler.
Why Are So Many Desert Animals Pale or Sandy Colored?
Light colors reflect more sunlight than dark ones, so a pale coat stays a little cooler! The sandy color also works as camouflage on pale ground.
Where Do Desert Animals Find Water If There Is No Pond?
Many desert animals get most of their water from their food! Seeds, insects, and juicy plants all hold water.
How Does a Beetle Collect Drinking Water From Fog?
In the Namib Desert, fog rolls in from the ocean at dawn, and some beetles use it to drink! Fog droplets gather on the beetle's bumpy back.
How Do Animals Stay Warm on a Cold Desert Night?
Desert nights can get chilly, but animals have many ways to stay warm! Burrows, rock crevices, and nests protect them from the cold air above ground.
Why Do Lizards Switch Between Sun and Shade All Day?
A lizard is cold-blooded, so it uses the outside world to set its body temperature! In the morning it basks on a warm rock to heat up.
Why Do Some Lizards Lift Their Feet One at a Time on Hot Sand?
The shovel-snouted lizard of the Namib Desert does a little dance when the sand is too hot! It raises two feet off the ground while resting on the other two, then switches.
Why Do Saharan Silver Ants Run on Such Long Legs?
Saharan silver ants search for food at midday, when it is so hot that other animals hide! Their long legs lift their bodies a little above the burning sand, where the air is cooler.
How Do Birds Cool Off Without Sweating?
Birds cannot sweat, but they have other ways to cool off! They open their beaks and flutter their throat skin so water evaporates from the mouth and throat.
What Is Summer Sleep, and Which Animals Do It?
Summer sleep is called estivation, and it is a lot like hibernation but in summer! Some animals rest through the hottest, driest months.
Why Do Some Desert Insects Have Waxy Skin?
Insects lose water through their outer shell, and in a dry place that can be a big problem! Many desert beetles and ants have a waxy layer on the outside.
How Does a Joshua Tree Depend on One Little Moth?
A Joshua tree depends on one little moth, and the moth depends on the tree! It is a partnership where each one helps the other.
How Do Animals Help Desert Seeds Spread?
Animals help desert seeds spread by carrying, burying, eating, and dropping them! A seed that is moved to a good spot has a much better chance to grow.
How Does a Sidewinder Snake Travel Across Loose Sand?
A sidewinder snake travels across loose sand by throwing its body sideways in loops! Only two small spots touch the ground at a time.
Why Can a Horned Lizard Look Like a Flat Rock?
A horned lizard can look like a flat rock thanks to its flat body, its colors, and its spiky skin! That disguise helps it hide from hunters.
How Does the Tiny Elf Owl Find a Home in a Cactus?
The tiny elf owl finds a home in a cactus by moving into a hole that a woodpecker made! The hole is cool, safe, and ready to use.
Why Does the Sand Cat Have Furry Feet?
The sand cat has furry feet to protect its paws from scorching and freezing sand! The fur also helps it grip loose sand, a bit like snowshoes in snow.
Why Do Honeypot Ants Have Balloon-Shaped Bellies?
Honeypot ants have balloon-shaped bellies because they are living storage jars! They hold sweet food for the whole colony.
How Does the Sandfish Lizard Swim Through Sand?
The sandfish lizard swims through sand by wiggling its smooth body like a fish! Its legs tuck against its sides, and its scales are very smooth.
How Do Bats Help Desert Plants?
Bats help desert plants by carrying pollen from flower to flower at night! The bats drink sweet nectar, and pollen from the flowers dusts their fur.
How Do Desert Elephants Live Where It Hardly Ever Rains?
Desert elephants live where it hardly ever rains by walking far and digging for water! They remember where water can be found, even if it has been a long time.
How Do Desert Animals Keep Sand Out of Their Eyes and Noses?
Desert animals keep sand out of their eyes and noses with built-in goggles and filters! Nature gave them special eyelids, eyelashes, and nostrils, all made for blowing sand.
How Do Scientists Find Out Which Animals Visit a Desert at Night?
Scientists find out which animals visit a desert at night using camera traps and clues! They look for tracks, droppings, and burrows, and they record sounds.
How Can You Read Animal Tracks in the Sand?
You can read animal tracks in the sand, because every track tells a story! The shape shows the animal's foot.
Why Do Tiny Fish Live in Only One Desert Pool?
Tiny fish live in only one desert pool because they got trapped there as the land dried out! The Devils Hole pupfish lives in a single pool in a cave in the Nevada desert.
How Do Desert Animals Sense That Rain Is Coming?
Desert animals sense that rain is coming by noticing clues that people often miss! Changes in the air, smells, and sounds can all signal a storm.
What Should You Do If You See a Snake or Scorpion Outdoors?
If you see a snake or scorpion outdoors, stay calm, back away slowly, and tell a grown-up right away! Most wild animals do not want to bother people.
Why Do Some Desert Animals Need People’s Help to Survive?
Some desert animals need people's help because they live where water and food are scarce! That means even small changes can matter a lot.
From Book 17: The Rainforest Expedition (52)
Why Are There So Many Insects in Rainforests?
Warm, wet weather all year means insects never have to sleep through a winter. There are plenty of leaves, flowers, wood, and fruit to eat, plus countless hiding places.
How Do So Many Animals Share One Rainforest Without Crowding Each Other Out?
Each kind of animal has its own job, food, and place to live. Scientists call this a niche.
Why Are Termites and Beetles Good for a Forest?
Termites and wood-boring beetles chew dead trees into small pieces. Inside termites' guts live tiny microbes that digest wood.
Where Do Animals Shelter When It Pours in the Rainforest?
When it pours in the rainforest, many animals tuck under large leaves, crawl into tree holes, or burrow into the ground. Birds sit close to the trunk or under thick leaves, and butterflies fold their wings.
How Do Insects and Frogs Take Advantage of the Rainy Season?
When the rains arrive, many frogs gather at fresh pools and breed. Insects also emerge in huge numbers, because fresh leaves and puddles provide food and places for eggs and young.
How Do Monkeys Swing and Leap From Branch to Branch?
Monkeys and apes swing and leap using strong arms, grippy hands, and clever balance! Gibbons swing hand over hand, and many monkeys jump between branches.
Why Do Some Monkeys Have Tails That Can Grab Like a Hand?
Some monkeys have tails that grip like an extra hand! Spider monkeys and howler monkeys have grabbing tails, which scientists call prehensile.
How Do Animals Glide From Tree to Tree?
Some rainforest animals cannot fly, but they can glide! They spread out skin, ribs, or feet like a parachute and sail from tree to tree.
How Do Tree Frogs Stick to Leaves?
Tree frogs have sticky toe pads that cling to leaves, even wet, upside-down ones! The pads are covered in tiny bumps and a thin layer of slippery liquid.
What Is the Smallest Frog in the World?
The smallest frog in the world is only about as long as a small pea! It lives in the rainforest of Papua New Guinea.
Why Are So Many Rainforest Birds Brightly Colored?
Rainforest birds wear bright colors to send messages! Colors help birds find friends, show they are healthy, and tell their own kind from look-alikes.
How Do Fruit Bats Find Ripe Fruit in the Dark?
Fruit bats find ripe fruit in the dark using a super sense of smell and big, night-ready eyes! They can sniff a ripe fruit from far away.
Why Do Howler Monkeys Howl So Loudly?
Howler monkeys howl so loudly because their bodies have a built-in loudspeaker! A special enlarged throat bone works like an echo chamber.
How Do Weaver Ants Build Nests From Living Leaves?
Weaver ants build their nests by pulling living leaves together and stitching them with silk! Hundreds of workers team up for the job.
How Do Sleeping Animals Stay Safe in the Treetops?
Sleeping animals stay safe in the treetops by choosing places that hunters cannot easily reach! Some sleep in nests, some in tree holes, and some on thick branches.
How Can a Snake Climb a Smooth Tree Trunk?
Tree snakes climb smooth trunks using light bodies, grippy belly scales, and clever curves! Even tiny bumps in the bark give them something to push against.
How Can a Frog Become See-Through?
Glass frogs have almost see-through bellies, and they can become even clearer when they rest! You can see their hearts and organs through their skin.
Why Do Butterflies Gather at Muddy Puddles?
Butterflies gather at muddy puddles to get minerals they cannot find in nectar! Scientists call this behavior puddling.
Why Do Animals Use Vines as Highways?
Animals use woody vines called lianas as highways high above the ground! Lianas wrap from tree to tree, making bridges across gaps in the canopy.
How Do Rainforest Animals Avoid Shouting Over One Another?
Rainforest animals share the soundscape like singers in a choir! Each species tends to call at its own pitch or its own time.
Why Do Some Rainforest Animals Eat Clay?
Some rainforest animals eat clay because it gives them things their food lacks! Parrots and macaws gather at steep riverbanks called clay licks.
How Do Animals High in the Canopy Get Water to Drink?
Animals high in the canopy drink from tiny pools and puddles in the treetops! Plants called bromeliads catch rain in their leaves like little cups.
How Can One Rainforest Tree Hold Thousands of Insects?
One rainforest tree can be a whole city for insects! Scientists counted thousands of insects living in the branches of a single treetop.
Why Do Monkeys Spend So Much Time Grooming Each Other?
Monkeys groom each other to clean fur and to build friendships! Grooming removes dirt and tiny pests from fur.
How Do Canopy Animals Know Which Tree Is Fruiting?
Canopy animals find fruiting trees using their eyes, their noses, and their memories! A ripe tree sends out clear signals.
Why Do Morpho Butterflies Flash Bright Blue?
A morpho butterfly's wings flash bright blue because of tiny structures, not blue paint! The wing scales bounce blue light back to your eyes.
Why Do So Many Animals Live in the Canopy Instead of on the Ground?
So many animals live in the canopy because that is where the food and sunlight are! The treetops are full of leaves, flowers, and fruit.
How Do Pitcher Plants Trap Insects?
Pitcher plants trap insects in cup-shaped leaves with a slippery rim! Inside the cup is a pool of liquid that digests the insects.
Why Can’t Brazil Nut Trees Grow Well Without a Rodent and a Bee?
Brazil nut trees need two helpers, a big bee and a rodent called the agouti! The bee pollinates the flowers, and the agouti plants the seeds.
Why Do Leafcutter Ants Carry Pieces of Leaves They Never Eat?
Leafcutter ants carry leaf pieces home, but they never eat them! The leaves are food for a garden.
How Do Army Ants Build Bridges with Their Own Bodies?
Army ants link their own bodies together to make living bridges! When a gap is in the way, workers hold on to each other with their legs and tiny hooks.
Why Do Some Ants Live Inside Special Trees?
Some ants live inside special trees because the tree gives them a home and food! In return, the ants protect the tree from hungry insects and smothering vines.
How Do Hummingbirds and Heliconia Flowers Fit Together Like a Lock and Key?
Some rainforest hummingbirds and flowers fit together like a lock and key! The bird's beak and the flower's tube have the same curve.
Why Do Birds Visit Red Flowers but Bees Prefer Blue and Yellow?
Flowers use color to invite the right visitors! Birds can see red very well, but bees see colors differently, so red looks dull to them.
How Do Some Birds Follow Army Ants to Find Food?
Some birds follow army ants because the ants chase food out of hiding! The birds do not eat the ants.
How Does a Bucket Orchid Make Bees Take a Bath?
A bucket orchid has a flower shaped like a bucket, filled with liquid! Male orchid bees come to collect its perfume, and some slip in for a splash.
How Do Dung Beetles Help the Forest Floor?
Dung beetles are the clean-up crew of the forest floor! They roll or bury animal droppings, which puts nutrients back into the soil.
How Do Poison Dart Frog Parents Carry Tadpoles to Tiny Pools?
Poison dart frog parents carry their tadpoles to tiny pools high in the trees! The tadpoles wriggle onto a parent's back and ride up the trunk.
How Can a Frog Smaller than Your Thumb Be So Loud?
A tiny frog can be loud because it uses its whole body like a speaker! The coquí frog of Puerto Rico is about the size of a quarter.
Why Do Some Rainforest Spiders Live Together in Giant Webs?
Most spiders live alone, but a few kinds in the Amazon live in big family groups! Hundreds or thousands share one giant web.
Why Are There More Kinds of Beetles than Anything Else?
There are more kinds of beetles than any other animal group! About one out of every four known animal species is a beetle.
Why Do Some Rainforest Bees Have No Sting?
Some rainforest bees have no sting at all! Their stingers are so small that they do not work.
Why Does the Atlas Moth Have No Mouth as an Adult?
The atlas moth has no working mouth as an adult because it does all its eating as a caterpillar! It stores up fat, and that fat powers its short adult life.
How Strong Is a Rhinoceros Beetle?
Rhinoceros beetles are super strong for their size! Some, like the Hercules beetle, can lift many times their own weight.
How Do Big Fruit-Eating Birds Plant New Trees?
Big fruit-eating birds are gardeners of the forest! They swallow whole fruit, carry the seeds far away, and drop them in new places.
How Do Glasswing Butterflies Get See-Through Wings?
Glasswing butterflies have see-through wings because of tiny structures, not color! Their clear wings have almost no colored scales.
What Can Happen to a Rainforest If One Kind of Animal Disappears?
In a rainforest, animals and plants are linked like threads in a web! When one kind of animal disappears, other living things can be affected too.
How Can Two Look-Alike Rainforest Animals Turn Out to Be Different Species?
Two animals can look almost the same and still be different species! Scientists look at calls, DNA, and who the animals mate with.
What Happens to Animals When a Forest Is Cut Into Small Pieces?
When a forest is cut into small pieces, animals have a hard time finding what they need! Open ground can be a barrier, and small patches may lose species over time.
How Do Rangers Help Protect Rainforest Animals and Plants?
Rangers help protect rainforest animals and plants by watching over the forest every day! They walk or boat through protected areas and work with nearby communities.
How Do Wildlife Rescue Centers Help Animals Return to the Forest?
Wildlife rescue centers care for animals that are hurt or have lost their parents! Their goal is to help each animal get ready to return to the forest.
How Do Birds That Visit Your Backyard Depend on Rainforests?
Many birds that visit your backyard spend part of the year in tropical forests! They nest in Canada and the United States in summer.
From Book 18: The Polar Expedition (33)
Why Don’t Reindeer Follow a Day-And-Night Clock in the Arctic?
Scientists found that reindeer in the Arctic do not have a strong 24-hour body rhythm! Instead of following day and night, they eat and rest in short cycles.
What Do Animals Do During the Long Polar Night?
During the long polar night, animals do different things! Some leave, some sleep deeply, and some stay active.
Why Are Arctic Summers So Full of Mosquitoes?
Arctic summers are full of mosquitoes because thawed ground makes thousands of shallow ponds where mosquito eggs hatch! The swarms come out all at once.
How Do Polar Animals Stay Warm Without a Heater?
Polar animals wear built-in winter coats made of fur, feathers, and fat! These layers trap heat close to the body, so the cold stays outside.
How Do Seals Keep Their Flippers Warm in Icy Water?
Seals keep their flippers from wasting heat by using a clever plumbing trick! Warm blood going out to the flipper passes its heat to the cooler blood coming back.
How Can Birds Stand on Ice Without Freezing Their Feet?
Birds can stand on ice because their legs have a built-in heat-saving trick! Warm blood heading to the feet gives its heat to cool blood coming back up.
Why Do Many Arctic Animals Have Small Ears and Short Tails?
Many Arctic animals have small ears and short tails because small body parts lose less heat! Ears, tails, and legs have lots of surface for their size, and heat escapes through surfaces.
Why Are Polar Animals Often Big and Round?
Polar animals are often big and round because a big, round body loses heat slowly! A large body has less skin compared with the amount of body inside.
Why Do Snowy Owls Have Feathers on Their Feet?
Snowy owls have feathers on their feet to wear built-in fluffy socks! The feathers trap warm air and keep skin from touching cold snow.
How Do Reindeer Find Food Under the Snow?
Reindeer find food under the snow by smelling it and digging for it! Even under a foot of snow, they can sniff out their winter snack.
Why Do Reindeer Eyes Turn From Gold to Blue?
Reindeer eyes change color with the seasons, from gold in summer to blue in winter! The change helps their eyes see better when the light is very different.
How Can Some Fish Live in Water That Is Colder than Freezing?
Some fish can live in water colder than freezing because they make their own antifreeze! The antifreeze is made of special proteins in their blood and body fluids.
How Can an Arctic Ground Squirrel Survive Below Freezing?
Arctic ground squirrels survive below freezing by supercooling their bodies! During hibernation, their body temperature drops to about 27 degrees Fahrenheit.
Why Don’t Polar Bear Paws Slip on Ice?
Polar bear paws do not slip on ice because they are covered with tiny bumps! The bumps grip the ice like a rubber doormat.
How Deep Can Emperor Penguins Dive?
Emperor penguins can dive more than 1,800 feet deep, deeper than a skyscraper is tall! They can also stay underwater for more than 20 minutes.
How Do Seals Breathe Through Holes in the Ice?
Seals breathe through holes in the ice that they keep open themselves! They are mammals, so they must come up for air.
Do Worms Really Live in Glaciers?
Yes, worms really live in glaciers! They are called ice worms.
Why Do Sled Dogs Curl Up in the Snow to Sleep?
Sled dogs curl up in the snow to sleep because it keeps them warm! Their thick coats, curled-up bodies, and bushy tails work together.
What Are Walrus Tusks For?
Walrus tusks are long teeth that help walruses in lots of ways! They keep growing for a walrus's whole life.
How Do Polar Animals Know When Winter Is Coming?
Polar animals know winter is coming by watching how long the days are! The length of the day is the same every year, even when the weather is odd.
What Is Krill, and Why Does It Matter So Much?
Krill are small, shrimp-like animals that matter hugely to the Southern Ocean! They eat tiny plants and are eaten by almost everyone.
Why Is Sea Ice a Nursery for Baby Animals?
Sea ice is a nursery because it gives young animals safety, warmth, and food! Many babies are born or grow up on and around the ice.
Why Do Whales Visit Polar Seas to Eat?
Whales visit polar seas to eat because summer there is an enormous buffet! The water is full of krill and fish.
How Can a Bowhead Whale Live for 200 Years?
Bowhead whales can live around 200 years, longer than any other mammal! They live in cold water and grow very slowly.
Why Do Arctic Bird Cliffs Have Bright Green Grass and Orange Rocks?
Arctic bird cliffs are green and orange because seabirds feed the plants without trying! Their droppings work like fertilizer.
How Old Can a Greenland Shark Get?
A Greenland shark may live for hundreds of years! Scientists estimate some are 250 to 500 years old.
What Are Seal Whiskers For?
Seal whiskers are super-sensitive detectors that help seals find fish! They can feel tiny ripples in the water.
Why Do Some Seals Sing Under the Ice?
Some seals sing under the ice because sound travels far in water! Male Weddell seals and bearded seals make long trills and whistles.
How Can Satellites Find Penguins From Space?
Satellites can find penguins from space by spotting their droppings! The droppings stain the ice and rocks a reddish brown.
Why Do Polar Animals Grow So Slowly?
Polar animals grow slowly because cold slows down the chemistry in their bodies! Many take years to mature and live for decades.
What Happens to Seals and Seabirds When Sea Ice Shrinks?
Seals, seabirds, and other animals use sea ice, so changes in the ice mean changes for them. When the ice forms later or melts earlier, animals may need to adapt.
How Do Seals Help Scientists Study the Ocean?
Seals help scientists by carrying tiny sensors into places no ship can go! The sensors measure the ocean while the seal swims and dives.
How Can Kids Help Scientists Count Penguins?
Kids can help count penguins from anywhere in the world, with a grown-up's help! Cameras in Antarctica take thousands of pictures of penguin colonies, all year long.
From Book 19: The River Expedition (17)
Why Do River Fish Face Upstream?
River fish usually point their noses into the current, which means they face upstream! Facing the flow helps them breathe, eat, and stay steady.
How Do Fish Hold Still in Fast Water?
Fish hold still in fast water by using smart body tricks and smart hiding spots! Smooth shapes, calm pockets, and strong fins all help.
How Do River Insects Breathe Underwater?
Many young river insects breathe underwater with gills, thin feathery parts that pull oxygen out of the water! Different insects wear their gills in different places.
Why Do River Insects Let Go and Drift Downstream at Night?
After dark, many river insects let go of the rocks and float downstream. Scientists call it drift!
What Is a Dipper, the Bird That Walks Underwater?
The American dipper is a small gray songbird that walks underwater to find food! It lives beside fast mountain streams.
Why Do Salmon Swim Up Rivers?
Many salmon hatch in a river, swim out to the ocean to grow, and then return to the river where they were born! They go home to lay their eggs.
How Do Young Fish Grow Up in a River?
Young fish grow up in safe nests and shelters, then slowly move to bigger water as they get strong! They hide, nibble tiny bugs, and grow.
Why Do Fish Leap Out of Rivers?
Fish jump out of rivers for lots of different reasons! Some are hunting, some are escaping, and some are traveling.
Why Do Frogs and Tadpoles Live in Quiet Corners of a River?
Frog eggs and tadpoles are soft and small, so they would be swept away in fast water! That is why they stay in calm corners.
How Do Trees Along a Riverbank Help the Animals in the Water?
Trees along a riverbank are green helpers that take care of the animals in the water! They give shade, food, and shelter to fish, insects, frogs, and birds.
How Does a River Feed the Animals Along Its Banks?
A river is like a food highway that feeds animals along its banks! Fish, insects, and plants bring in hungry visitors.
Which Animals Wake Up Along a River at Night?
When the Sun sets, a whole new crew wakes up along the river! Bats, owls, raccoons, muskrats, and frogs all get busy, and fireflies may blink too.
How Do Animals Cross a Rushing River?
Animals cross rivers in many clever ways, but they choose their crossing spots carefully! Some swim, some fly, and some float, and some even team up.
How Do Fish Get Past a Dam?
Fish get past a dam using a fish ladder, which works like a staircase of water! Many fish must swim upstream to lay their eggs.
What Happens to River Animals When the Water Gets Low?
When river water gets low, animals find cooler, deeper spots to wait it out! Fish, insects, and frogs each have their own tricks.
How Do Fish Survive Under River Ice?
Fish survive under river ice because the water below stays liquid! The ice on top acts like a lid that keeps the water underneath from freezing solid.
How Do Scientists Count Fish They Can’t See?
Scientists count fish they can't see with gentle tools like cameras, sound, and tiny tags! The goal is to learn how many fish live in a river.
From Book 20: The Mountain Expedition (14)
Why Do Different Animals Live at Different Heights on a Mountain?
Different animals live at different heights because each one fits a certain climate! Food, shelter, and temperature decide who lives where.
Do Animals Move Up and Down Mountains?
Yes, many mountain animals follow the seasons up and down the slopes! This yearly up-and-down trip is called altitudinal migration.
Why Are Some Mountain Plants and Animals Moving to Higher Ground?
Some mountain plants and animals are moving to higher ground because the climate is getting warmer! When it warms, the cool zone shifts uphill.
How Do Animals Like Yaks and Llamas Cope with Thin Air?
Yaks and llamas cope with thin air because their bodies are built for high places! Yaks live in the Himalayas, and llamas live in the Andes.
How Do Big Birds Soar Over Mountains Without Flapping?
Big birds soar over mountains by riding invisible rising air! Eagles and condors spread their wings and let the air lift them.
How Do Mountain Animals Find Food When Snow Covers Everything?
When snow covers everything, each mountain animal has its own food plan! Some store food, some sleep, and some dig.
How Can Bar-Headed Geese Fly Over the Himalayas?
Bar-headed geese fly over the Himalayas, the highest mountains on Earth, with big lungs and super blood! They travel between India and Central Asia.
What Is the Highest-Living Animal on Earth?
The highest-living animal on Earth is a tiny jumping spider! It has been found at about 22,000 feet on Mount Everest, higher than any other known animal that lives there all year.
Which Mountain Animals Have Built-In Snowshoes?
Snowshoe hares, lynx, and ptarmigan all have built-in snowshoes! Large, furry feet spread their weight out over the snow.
How Do Scientists Count Animals on Steep, Snowy Slopes?
Scientists count animals on steep, snowy slopes using clever tools from far away! Climbing close to wild animals can be risky for people and can scare the animals.
Which Animals Live in the Canadian Rockies?
The Canadian Rockies are home to lots of amazing wild animals! Each animal lives in the zone that suits it best.
How Does a Bird Help Plant Mountain Forests?
A bird called Clark's nutcracker helps plant mountain forests! It hides seeds in the ground, and some are never found again.
Why Are Some of the Oldest Weird Animal Fossils Found High in the Rocky Mountains?
Some of the oldest, weirdest animal fossils are found high in the Rocky Mountains. The Burgess Shale, in Yoho National Park, holds fossils about 508 million years old.
How Do Wolves and Bears Get Across the Trans-Canada Highway in Banff?
Wolves and bears get across the Trans-Canada Highway in Banff by using wildlife crossings. There are tunnels under the road and grassy bridges over it.
From Book 21: The Magnet Expedition (9)
How Do Sea Turtles Use Earth’s Magnet to Find Their Way?
A baby sea turtle hatches on a beach, swims out to sea, and years later returns to lay its eggs on the very same beach. How does it find its way across a huge ocean?
Do Birds Really Have a Built-In Compass?
Every year, many birds fly thousands of miles to warmer places and then back again. They do not use maps or GPS.
Can Sharks Use a Magnetic Map to Swim Home?
Sharks swim across huge oceans and somehow find their way home. Scientists wondered if they might use a magnetic map.
How Might Salmon Use Earth’s Magnet to Return to Their Home River?
Salmon begin their lives in a small river. They swim out to the ocean for years, and then return to the very same river where they were born.
Do Cows and Deer Really Face North and South?
In 2008, some scientists made a surprising claim. They said cows and deer might line up north and south when they graze or rest.
How Do Monarch Butterflies Use a Magnetic Compass?
Every fall, monarch butterflies fly thousands of miles to Mexico. Even though they are tiny, they find their way to the very same forests.
How Do Mole-Rats Use Magnetism Underground?
Deep underground, there are animals that live in total darkness. Ansell's mole-rats in Africa live in dark tunnels and have very poor eyesight.
How Do Scientists Test Whether an Animal Can Sense Magnetism?
How can a scientist find out whether an animal can sense magnetism? The animal cannot tell us, so scientists must be clever.
Could Bees or Ants Use Magnetism to Find Their Way?
Honeybees and ants are tiny, but they are great at finding their way home. Could magnetism be part of their secret?
From Book 22: The Energy Expedition (3)
Why Do Small Animals Eat So Much for Their Size?
A tiny shrew eats almost all day long. An elephant eats a lot too, but far less for its size.
Why Do Migrating Birds Eat So Much Before a Long Trip?
Some birds fly across whole oceans without stopping to eat. That takes a lot of fuel.
How Do Deep-Sea Animals Get by with So Little Food?
The deep ocean is dark and cold. No sunlight reaches it, so no plants grow.
From Book 23: The Flight Expedition (20)
How Do the Four Forces Explain a Bird, a Plane, and a Kite?
A bird, a plane, and a kite all stay in the air. They look so different.
How Do Feathers Turn a Bird's Wing Into a Flying Machine?
A bird's wing is covered in feathers. They turn a wing into a flying machine.
Why Do Some Birds Flap Constantly While Others Soar?
Some birds flap and flap. Others glide for hours on still wings.
How Do Light, Hollow Bones Help Birds Fly?
Birds need to be light to fly. Many of their bones are hollow!
How Do Birds Land So Gracefully?
Birds land on a tiny branch with perfect balance. It looks so easy.
What Do a Bird's Tail Feathers Do in the Air?
A bird's tail is like a steering wheel with feathers. It acts like a rudder and an elevator at once.
Why Can Ostriches and Penguins Not Fly?
Ostriches and penguins are birds. But neither one can fly.
How Can an Insect Beat Its Wings Hundreds of Times Each Second?
A honeybee beats its wings hundreds of times each second. How can any muscle move so fast?
How Does an Insect's Chest Work Like a Wing-Wiggling Box?
Here is a surprise about insect wings. The muscles that move them are not in the wings.
How Is a Bat's Wing Different From a Bird's Wing?
A bat's wing is very different from a bird's wing. It has no feathers at all.
What Is the Difference Between Flying and Gliding for an Animal?
Some animals fly and some animals glide. They are not the same thing.
Can Snakes and Frogs Glide Through the Air?
Snakes and frogs can glide through the air! It sounds like a tall tale.
How Do Baby Birds Learn to Fly?
Baby birds are born without the ability to fly. They have to learn.
Can Any Bird Sleep While Flying?
Could a bird sleep while it is flying? It sounds impossible.
How Far Can a Bird Fly Without Stopping?
Which bird can fly the farthest without stopping? The record is almost unbelievable.
How Do Birds Change the Shape of Their Wings?
A bird can change the shape of its wings in the air. It can bend, fold, and fan them.
Why Do Some Birds Have Long, Pointed Wings and Others Short, Round Ones?
Some birds have long, pointed wings. Others have short, round ones.
How Do Baby Spiders Fly on Silk Threads?
Baby spiders can fly! They do it without any wings.
What Can Engineers Learn From Flying Animals?
Flying animals have had millions of years to practice. Engineers watch and learn from them.
How Do Airports Keep Birds Away From Runways?
Birds and planes should not share a runway. Airports use many gentle ways to keep birds away.
From Book 24: The Underground Expedition (16)
What is inside an ant nest?
An ant nest is a maze of tunnels and rooms underground. There are chambers for the queen, for eggs and larvae, for storing food, and even for waste.
How do ants get through the winter underground?
When it gets cold, ants move deeper in their nests, below the frost line where the soil stays warmer. They slow down, gather in clusters, and eat food stored earlier or live off body fat.
How does a worm push through hard soil without legs?
An earthworm has two sets of muscles. One squeezes it long and thin, and the other makes it short and fat.
How can a worm sense the world without eyes?
Worms have no eyes, but their skin has special cells that sense light, so they can tell dark from bright. They also feel vibrations, touch, and chemicals.
Why do most animals that live in the soil see so poorly?
Under the ground there is little to no light, so eyes are not very useful. Many soil animals rely on touch, smell, and vibrations instead.
Do animals underground ever run out of air?
Usually not. Soil is full of air-filled gaps, and fresh air seeps in from above.
How can some frogs and toads dig themselves into the ground?
Spadefoot toads have hard, spade-shaped bumps on their hind feet. They wriggle backward and dig down into loose soil, sinking out of sight.
How can thousands of garter snakes share one winter den?
In Manitoba, red-sided garter snakes gather in deep cracks and caverns in limestone, where it stays above freezing all winter. Tens of thousands share these dens.
Why do so many kinds of bees nest in the ground?
About seven out of ten bee species dig their nests in the soil. Each female digs a tunnel and makes little rooms stocked with pollen for her babies.
How do animals find food in the dark ground?
In the dark soil, animals use smell, taste, touch, and vibrations. A worm follows chemicals from decaying leaves.
Why do many animals dig to escape heat and cold?
A few feet underground, the temperature stays much steadier than the air above. It's cooler in summer and warmer in winter.
Why do prairie dogs build whole underground towns?
Prairie dogs live in groups called coteries within big towns of tunnels. Their burrows have several chambers for sleeping, nursing, and storing food, and they have lookout mounds at the entrances.
How do small insects survive the winter in the soil?
Many insects hide in the soil or leaf litter during winter, where it does not get as cold. Some, like bumblebee queens, dig into the ground and sleep.
How do soil animals share food and recycle nutrients?
In the soil, plants and animals that die become food. Bacteria and fungi break them down.
How do fish that live in dark caves get by without eyes?
Some fish live in caves where no light ever shines. Over many generations, cave-dwelling populations of some species, such as the Mexican tetra, have lost their eyes and...
How can dogs find food that grows underground?
Truffles are fungi that grow underground near tree roots. They give off a strong smell that dogs can detect from far away.