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Explore the World 11
Amazing Animals 112
What If? Lab 13
How Things Work 2

How Things Work How do birds fly? Watch wings and feathers in slow motion. Compare flapping, soaring, and gliding, then experiment with different wing shapes and flying conditions.
How Things Work How do birds build nests? Compare designs and arrange virtual materials that support model eggs.
What If? Lab What if birds forgot how to build nests? Nests keep eggs and chicks safe from predators and the weather, and birds build them in amazing ways: from twigs, grass, mud, hair and even spider silk. Imagine every bird forgetting how to build one. Then meet the birds that already manage without, from cliff-ledge murres to emperor penguins.
Animal Greater bird-of-paradise The greater bird-of-paradise is a rainforest bird of southern New Guinea and the Aru Islands. Males have a yellow head, a green throat, long tail wires and huge golden flank plumes, which they show off in group dances high in tall trees to win a female.
Natural wonder Volga The Volga is Europe's longest river. It rises in the Valdai Hills northwest of Moscow and flows about 3,530 kilometers to the Caspian Sea, all within Russia. Almost half of Russia's people live in its basin. Big dams now turn much of it into a chain of long lakes, and its huge delta shelters up to 750,000 waterbirds in mild winters.
Country Senegal Senegal is a country at the far western tip of Africa, on the Atlantic Ocean. Its capital, Dakar, sits on the westernmost point of the continent. About 19 million people live there, and the Senegal River, wetlands full of birds and quiet mangrove deltas make it a place of water as well as dry grassland.
Natural wonder Pantanal The Pantanal is one of the world's largest freshwater wetlands, mostly in Brazil and reaching into Bolivia and Paraguay. Each rainy season its rivers overflow and flood the lowlands, making shallow lakes and marshes; in the dry season the water slowly drains away. This rhythm feeds an amazing number of animals, from jaguars and giant otters to about 600 kinds of birds.
Country Mauritania Mauritania is a large country in northwest Africa where the Sahara meets the Atlantic Ocean. Dunes cover about half the land, ancient trading towns stand by desert oases, and many kinds of migrating birds spend the winter on its coast. About 5.3 million people live there.
Country The Gambia The Gambia is the smallest country on Africa's mainland, a narrow strip of land on both banks of the Gambia River. Except for a short Atlantic coast, it is surrounded by Senegal. More than 500 kinds of birds live there, and about 2.8 million people lived there in 2025.
Animal Rock pigeon The rock pigeon, also called the rock dove, is the pigeon you see in city squares. Its wild ancestors nest on sea cliffs and mountain ledges, and city pigeons use buildings as if they were cliffs. Pigeons are famous for finding their way home from far away.
Animal House sparrow The house sparrow is one of the most widespread songbirds in the world. It is native to Europe, Asia and North Africa, but people released it in many other places, and now it lives in towns and farms almost everywhere people do. Its numbers have fallen sharply in some places, including Britain and North America.
Animal European robin The European robin is a small songbird of Europe's woods, parks and gardens, famous for its orange-red breast. It sings almost all year round, even at night under streetlights, and it defends its patch fiercely. Young robins have no red breast at all: they are speckled with golden brown.
Natural wonder Mississippi River The Mississippi River flows about 3,770 kilometers from Lake Itasca in Minnesota to the Gulf of Mexico, through the middle of the United States. Its basin drains about 40 percent of the continental United States. Long ago Native Americans paddled canoes on it; later came steamboats, and today huge barges carry grain and fuel. Millions of birds follow it when they migrate.
Animal Roseate spoonbill The roseate spoonbill is a bright pink wading bird with a long, flat bill shaped like a spoon. It sweeps its bill from side to side through shallow water and grabs the shrimp or small fish it feels. Its pink color comes from the food it eats.
Animal Southern crested caracara The southern crested caracara is a large bird of prey from South America and a surprising member of the falcon family. It has a black crest, a bare orange-red face and long yellow legs, and it eats almost anything: dead animals, small creatures and insects.
What If? Lab What if insects vanished? Insects eat plants, and birds, mice and bears eat insects. In our forest food web, take the insects out and see who could go hungry and who could change. Then find out why scientists are counting insects carefully, and how people help them.
What If? Lab What if you had no teeth? Your teeth cut, tear and grind food into small pieces so you can swallow it. Imagine eating with no teeth at all! Find out what each kind of tooth does, how baby teeth make way for adult teeth, and how birds manage without any teeth, using a muscly stomach called a gizzard.
What If? Lab What if penguins could fly? Penguins are birds whose wings became stiff flippers for swimming. Their ancestors flew, but today's penguins are superb divers instead. Imagine a penguin that could fly: what would it need to change, and what might it lose underwater?
What If? Lab What if seeds could not travel? Seeds ride the wind, float on water, hide in fruit that animals eat, and cling to fur and socks. What if every seed simply dropped under its parent plant? Explore crowded seedlings, wind and animal helpers, and the burrs that gave people an idea.
What If? Lab What if there were no wetlands? Marshes, swamps and bogs are wetlands: places where water covers the soil or sits just below it. EPA compares them to natural sponges that soak up rain and floodwater and let it go slowly. They also clean water and shelter many birds and young fish. Imagine a world with no wetlands, and follow what might change.
What If? Lab What if dinosaurs still lived today? Most dinosaurs died out 66 million years ago, after a huge asteroid hit Earth. One group survived: birds, which scientists count as living dinosaurs. Imagine the other dinosaurs had survived too. Where could they live, what would they eat, and how would they fit into today's world?
What If? Lab What if you could see like an eagle? Some eagles can see about twice as much fine detail as people can. Their big eyes are packed with light-sensing cells, and many birds of prey have two extra-sharp spots in each eye where we have one. Imagine trading eyes with an eagle and find out what you would gain, and what eagles might not see at all.
Animal Shoebill The shoebill is a tall gray bird of African swamps, named for its enormous bill shaped like a wooden shoe. It stands as still as a statue among the papyrus, then lunges forward to grab big, slippery fish such as lungfish.
Animal Tawny owl The tawny owl is a medium-sized woodland owl, about the size of a pigeon, with a round head, big dark eyes and brown, streaky feathers that hide it against tree bark. It hunts mice and voles at night on silent wings, and its hoots are a familiar sound at night.
Animal Bald eagle The bald eagle is one of North America's biggest birds, with a white head and tail, a dark brown body and a huge yellow bill. It lives near lakes, rivers and coasts and eats mostly fish. Once rare because of hunting and pesticides, it has made an amazing comeback.
Animal Wild turkey The wild turkey is a big, bronze-feathered bird of North American forests and clearings. It walks most of the time but can run, fly and even roost high in trees at night. By the early 1900s wild turkeys had become rare in many places, but people helped them come back, and now they live in every U.S. state except Alaska.
Animal Barn swallow The barn swallow is a small, speedy bird with a glossy blue back, a reddish throat and a long, deeply forked tail. It catches insects in the air, builds cup-shaped mud nests on barns and bridges, and makes long migrations between the Northern Hemisphere, where it nests, and the Southern Hemisphere, where it spends the winter.
Animal Golden eagle The golden eagle is one of the largest and fastest birds of prey in North America, and it lives across much of the Northern Hemisphere. It soars over mountains and open country on wings more than two meters wide and dives at tremendous speed to catch rabbits, hares and ground squirrels.
Geography River deltas A delta is land a river builds where it slows down and empties into a sea, a lake or another river. The slowing water drops its sand and mud, which pile up into low, flat, watery land. Many deltas are fan-shaped, like the Greek letter delta (Δ), but some look like a bird's foot.
Animal Scarlet ibis The scarlet ibis is a bright red wading bird of South America, red all over except for black wingtips. It probes mud and shallow water with its long, curved bill for crabs, crayfish and insects, and its color comes from pigments in its food.
Animal American crow The American crow is an all-black bird found across much of North America, from fields and beaches to city centers. It eats almost anything, lives in close family groups, gathers in huge winter roosts, and a University of Washington study found that wild crows can recognize and remember a human face.
Animal Andean condor The Andean condor is one of the largest flying birds in the world. With wings up to 3.2 meters across, it soars over the Andes Mountains of South America, barely flapping, as it searches for dead animals to eat. It is a vulture, nature's clean-up crew.
Animal Burrowing owl The burrowing owl is a small, sandy-brown owl with long legs and bright yellow eyes. Unlike most owls, it lives underground, in burrows dug by prairie dogs, ground squirrels or tortoises, or sometimes by the owls themselves. It lives in open grasslands and deserts from Canada to the tip of South America.
Animal Secretarybird The secretarybird is a bird of prey that hunts on foot. It strides across the African savanna on the longest legs of any raptor, walking 20 to 30 kilometers a day, and stamps on grasshoppers, mice, lizards and even snakes with lightning-fast kicks.
Animal Common ostrich The common ostrich is the tallest and heaviest bird alive. It cannot fly, but it is the fastest runner on two legs, sprinting at about 70 kilometers an hour across the savannas and deserts of Africa. It also lays the biggest egg of any living animal.
Animal Indian peafowl The Indian peafowl is a large bird of the pheasant family from South Asia. Males, called peacocks, have a bright blue neck and a long train of shimmering feathers decorated with eyespots, which they spread into a giant fan to impress females, called peahens. It is the national bird of India.
Animal Common starling The common starling, also called the European starling, is a glossy, spotted songbird from Europe, Asia and North Africa. It is a brilliant copycat that can imitate other birds and even car alarms, and in winter huge flocks swirl through the evening sky in shows called murmurations. People also carried starlings to North America, Australia and other places, where they now live in the wild.
Animal Red-tailed hawk The red-tailed hawk is probably the most common hawk in North America. It soars in wide circles over fields or waits on a pole or fence post, watching for voles, mice and rabbits, then drops down to catch them with its sharp talons.
Animal Common blackbird The common blackbird is a thrush found in gardens, parks and woods across Europe, North Africa and parts of Asia. Males are glossy black with a bright yellow-orange bill and eye-ring, females are brown, and on summer evenings males sing a mellow, fluting song from high perches.
Animal Eastern bluebird The eastern bluebird is a small thrush of open fields and parks in eastern North America, south to Central America. Males are bright blue with a rusty orange chest. Bluebirds watch from wires and fence posts, flutter down to catch insects, and nest in tree holes and in nest boxes that people put up for them.
Animal Great blue heron The great blue heron is the largest heron in North America. It wades slowly through marshes, rivers and ponds, or stands as still as a statue, then strikes like lightning with its dagger-shaped bill to catch fish, frogs and even small mammals.
Animal Peregrine falcon The peregrine falcon is a crow-sized bird of prey famous for its hunting dive, called a stoop. Diving from high above, it can reach about 320 kilometers per hour, making it the fastest animal on Earth. It lives on every continent except Antarctica, even in big cities.
Animal Philippine eagle The Philippine eagle is one of the largest and rarest eagles in the world. It lives only in the mountain rainforests of four Philippine islands, where it hunts monkeys, civets, flying squirrels and other forest animals. It is the national bird of the Philippines, and it is critically endangered.
Animal Superb fairywren The superb fairywren is a tiny Australian songbird that lives in family groups. In the breeding season the male is bright sky blue and black; the female is brown with an orange-red face. Older family members help feed the chicks, and mothers even call to their eggs before the chicks hatch.
Animal American flamingo The American flamingo is a tall, bright pink wading bird of the Caribbean. It gets its color from pigments in the tiny water animals and algae it eats, and it feeds by filtering water through its bent bill with its head upside down. Flamingos live and nest in huge, noisy groups.
Animal California condor The California condor is the largest wild bird in North America, a giant vulture with wings about 2.8 meters wide. In the 1980s only 22 were left. Thanks to a huge rescue effort, the US Fish and Wildlife Service counted 607 condors at the end of 2025, 392 of them flying free.
Animal Eurasian blue tit The Eurasian blue tit is a small, colorful songbird of woods, parks and gardens across Europe and western Asia. It hangs upside down to find caterpillars, nests in holes and nest boxes, and can lay a very large clutch of eggs once a year, timed for when caterpillars are plentiful.
Animal Goliath birdeater The Goliath birdeater is a giant tarantula from the rainforests of northern South America. With legs spreading about 28 centimeters and a weight of up to about 170 grams, it is described as the heaviest spider in the world. Despite its name, it eats mostly worms and insects, not birds.
Animal Northern cardinal The northern cardinal is a crested songbird of eastern North America and Mexico. Males are brilliant red with a black face; females are warm brown with red touches. Cardinals crack seeds with their thick bills, stay in the same area all year, and both males and females sing.
Animal African fish eagle The African fish eagle is a big eagle of Africa's lakes, rivers and coasts, with a white head, chest and tail and a chestnut-brown body. It snatches fish from the surface of the water, and its loud, ringing call is one of the best-known sounds of Africa.
Animal American goldfinch The American goldfinch is a small finch that eats almost nothing but seeds. In summer the male is bright lemon yellow with a black cap and black wings, and in winter both males and females turn a soft olive brown. Goldfinches wait until late summer to build their nests.
Animal Eurasian eagle-owl The Eurasian eagle-owl is one of the biggest owls in the world, with wings up to about 2 meters across, big orange eyes and two tall ear tufts. It lives across Europe and Asia, nests on rocky ledges and flies silently at night to catch rats, voles, hares and birds.
Animal Grey crowned crane The grey crowned crane is a gray African crane with a spiky crown of golden feathers, white and red cheeks and a red throat pouch. It is one of only two cranes that can perch in trees. It is the national bird of Uganda, and it is Endangered because its wetlands are disappearing.
Animal Resplendent quetzal The resplendent quetzal is a glittering green and red bird of the cloud forests of southern Mexico and Central America. Males grow long, flowing plumes, up to about 90 centimeters. Quetzals eat mostly small fruits related to avocados, and the bird is the national emblem of Guatemala.
Animal Steller's sea eagle Steller's sea eagle is one of the largest sea and fish eagles. Dark brown with bright white shoulders, tail and legs and an enormous orange-yellow beak, it nests in far eastern Russia and feeds mainly on salmon. In winter many fly south to Japan.
Animal Northern mockingbird The northern mockingbird is a slim gray songbird famous for copying sounds. It sings long strings of phrases, many borrowed from other birds, and sometimes sings all night. It lives in towns, farms and brushy places across the United States, Mexico and the Caribbean.
Natural wonder Danube The Danube is Europe's second-longest river, after the Volga. It begins as two small streams in Germany's Black Forest and flows about 2,850 kilometers east to the Black Sea, passing through 10 countries and four capital cities. For more than 2,000 years it has been a border, a highway for boats and a home for wildlife, and it ends in a giant delta of reeds, lakes and birds.
Animal Kākāpō The kākāpō is a large, moss-green parrot from New Zealand with an owl-like face. It cannot fly, it is active at night, and it eats only plants. It nearly died out, but careful work by New Zealand's Department of Conservation has grown the population to 325 birds (September 2026).
Animal Ocelot The ocelot is a medium-sized wild cat of the Americas, from southern Texas to northern Argentina. Its golden coat has chains of dark-edged spots, and no two ocelots look alike. It hunts mostly at night, catching mice, rats, lizards and birds, and it needs thick plants to hide in.
Animal Caracal The caracal is a sleek, reddish-gold wild cat of Africa, the Middle East and Central Asia to India. Its name comes from a Turkish word meaning "black ears", for its black-backed ears with long tufts. It hunts on the ground, but it can leap two meters or more into the air to catch birds.