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Animal Lion The lion is the only big cat that lives in a family group, called a pride. Lionesses hunt together, males guard the pride's land, and their roar can be heard about 8 kilometers away. Wild lions live in Africa, plus one small group in western India.
Animal Puma The puma, also called the cougar or mountain lion, is a big, slender cat with plain tan fur and a long tail. It lives in more of the Americas than any other wild cat, from Canada all the way to the southern tip of South America, in mountains, forests, deserts and swamps.
Animal Tiger The tiger is a huge cat with orange fur and dark stripes that help it hide in tall grass and forest shadows. It lives alone, hunts deer and wild pigs, and loves to swim. Wild tigers live only in Asia, and they are endangered.
Animal Jaguar The jaguar is the largest cat in North and South America. It lives near rivers and swamps, swims well, and has such a powerful bite that it can crack a turtle's shell. Most jaguars live in the Amazon rainforest.
Animal Cheetah The cheetah is the fastest land animal. It can go from standing still to 72 kilometers per hour in about two and a half seconds, and its top speed is around 100 kilometers per hour, as fast as a car on a highway. Cheetahs live mostly in Africa, with a very small group in Iran.
Animal Leopard The leopard is a strong, spotted big cat and the best climber of them all. It can carry its food high up into a tree, away from lions and hyenas. Leopards live in more kinds of places than any other big cat, from deserts to rainforests, across Africa and Asia.
Animal Snow leopard The snow leopard lives high in the mountains of Central Asia, where it is freezing cold and the ground is steep and rocky. Thick fur, huge furry paws and a tail almost as long as its body help it survive. It is so hard to spot that people call it the ghost cat of the mountains.
Animal Sand cat The sand cat is a small wild cat of the deserts of North Africa, Arabia and Central Asia. Its sandy coat hides it on the dunes, its big ears hear prey moving under the sand, and thick fur on the soles of its feet protects it from scorching days and freezing nights.
Animal Pallas's cat Pallas's cat, or the manul, is a small wild cat of the cold, dry grasslands and mountains of Central Asia. Its long, thick fur makes it look bigger than it really is, and its flat face and low, round ears help it peek over rocks without being seen. It hunts pikas and other small animals.
Animal Tiger shark The tiger shark is one of the biggest sharks in the sea. Young tiger sharks have dark spots and stripes like a tiger, which fade as they grow. It eats an amazing range of food, and it travels long distances between warm and cooler seas.
Animal Leopard seal The leopard seal is a large, slender seal of the icy seas around Antarctica, named for the dark spots on its gray coat. It is a fast, powerful hunter with a big head and long teeth, and it eats everything from tiny krill to fish, penguins and young seals.
Animal Leopard gecko The leopard gecko is a spotted lizard from the rocky deserts and dry grasslands of Pakistan, Afghanistan, northwestern India and Nepal. It hunts insects and scorpions at night, stores fat in its thick tail, and has real eyelids. It is also one of the most popular pet lizards in the world.
Animal Clouded leopard The clouded leopard is a forest cat of mainland Southeast Asia and the Himalayan foothills. It is named for the cloud-shaped patches on its coat, and it is an amazing climber that can creep headfirst down a tree trunk. It is Vulnerable, and fewer of them are left each year.
Animal California sea lion The California sea lion is an 'eared seal' of the west coast of North America. It is clever, playful and very noisy, with a bark like a dog's. Unlike true seals, it has ear flaps and can turn its back flippers forward to walk on land. Its numbers have grown a lot since it was protected.
Animal Golden lion tamarin The golden lion tamarin is a small, bright orange monkey with a lion-like mane. It lives only in the Atlantic coastal forest of Brazil. In the 1970s only about 200 were left in the wild; thanks to decades of work, a census in 2022 and 2023 counted about 4,800.
Animal Lion's mane jellyfish The lion's mane jellyfish is one of the biggest jellyfish in the world. Its bell is usually 30 to 50 centimeters across, but in very cold seas it can grow to about 2 meters, and hundreds of long, hair-like tentacles trail beneath it to catch food.
Animal Eastern tiger salamander The eastern tiger salamander is one of North America's biggest land salamanders: dark and shiny, with yellow or olive blotches. It spends most of its life in burrows, then walks to fishless ponds on rainy nights to lay its eggs. Its babies live in water and breathe with feathery gills.
Animal Eastern tiger swallowtail The eastern tiger swallowtail is a large butterfly of eastern North America. Males are yellow with black tiger stripes, while many females are dark, which helps them look like a bad-tasting butterfly. Its caterpillars disguise themselves as bird droppings, then turn green with big fake eyes.
What If? Lab What if you played catch on a merry-go-round? Roll a ball straight across a spinning merry-go-round and, to the riders, it seems to curve away. Someone standing on the ground sees it go straight. The same trick, on our spinning Earth, bends winds and makes big storms swirl.
Animal Eurasian lynx The Eurasian lynx is the largest of the four kinds of lynx. It has black ear tufts, a ruff of fur around its face, a short black-tipped tail and big furry paws for snow. It hides in forests and ambushes deer such as roe deer, and it has returned to parts of Europe where it had disappeared.
Animal Bobcat The bobcat is North America's most common wild cat, found from southern Canada across the United States to Mexico. It is bigger than a house cat, with a short tail, ear tufts and a spotted coat. It lives in forests, swamps, deserts and even some cities, and hunts mostly rabbits.
What If? Lab What if a turbine had a small generator? A wind turbine's blades catch the wind, but its generator turns that spin into electricity, and every generator has a top limit called its rated power. In our model, big blades in a strong wind make about 2.13 megawatts with a large generator. Swap in a 1-megawatt generator, and the turbine can never make more than 1 megawatt, however hard the wind blows.
What If? Lab What if a wind turbine had different blades? A wind turbine's blades sweep out a big circle, catching the wind that blows through it. Make the blades twice as long and the circle holds four times as much wind. In our model, that turns about 1.2 megawatts of electricity into about 4.9 megawatts, in the same wind. Find out why wind turbines keep getting bigger.
Animal Red lionfish The red lionfish is a striped reef fish with long, spiny fins that spread out like a lion's mane. It comes from the Pacific and eastern Indian Oceans, where it hunts small fish and shrimp at night. People released lionfish into the Atlantic Ocean, and there they have spread fast, eating many native reef fish.
Animal Ring-tailed lemur The ring-tailed lemur is a primate that lives only on Madagascar, a big island off the coast of Africa. It has a striped tail with 13 black and white rings, sunbathes with its arms spread wide, and lives in groups where the females are in charge.
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.
Country Singapore Singapore is a city-state, a country that is also one city, on an island at the southern tip of the Malay Peninsula in Southeast Asia. It is small but crowded: about 6.21 million people lived there in 2026, and its port is one of the busiest in the world.
Animal Great horned owl The great horned owl is a large, powerful owl with two long, earlike tufts of feathers on its head. It is one of the most common owls in North America and lives in almost any kind of semi-open place, from deserts and forests to city parks. It hunts mostly at night.
Natural wonder Chitwan National Park Chitwan National Park, in the lowlands of southern Nepal, was Nepal's first national park. Its sal forests, tall grasslands and rivers are home to the second-largest population of greater one-horned rhinoceroses in the world, 694 in 2021, and to Bengal tigers, 145 counted in and around the park in 2026.
Natural wonder Kaziranga National Park Kaziranga National Park lies beside the great Brahmaputra River in Assam, in northeastern India. Every year the river floods parts of the park, keeping its tall grasslands, marshes and pools alive. It is home to the world's largest population of greater one-horned rhinoceroses, more than 2,600 in 2024, which grew from only a handful about a hundred years earlier.
What If? Lab What if sharks disappeared? Sharks catch and eat other sea animals, and just having them around changes where those animals go. Follow what scientists have found in Australia's Shark Bay seagrass meadows and on coral reefs, where the evidence is still debated, and how some shark populations are recovering.
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.
Natural wonder Sundarbans The Sundarbans is a vast mangrove forest where the Ganges and Brahmaputra rivers meet the Bay of Bengal. It is shared by Bangladesh and India. Twice a day the tides flood its muddy islands, and its trees are made to live in salty water. It is one of the last homes of the Bengal tiger, and both countries protect it as a World Heritage Site.
Animal Blue whale The blue whale is the largest animal ever to live on Earth, bigger than any dinosaur. It is a baleen whale: instead of teeth it has bristly plates that strain huge mouthfuls of seawater to catch krill. Blue whales live in every ocean except the Arctic, and their deep calls are among the loudest sounds made by any animal.
Animal Common wasp The common wasp is a black and yellow striped insect that lives in a big family called a colony. Thousands of wasps share a round nest made of paper that they make by chewing wood. They catch insects such as caterpillars and flies to feed their young, which makes them useful garden helpers.
Animal Spotted hyena The spotted hyena is the largest of the hyenas and a skilled hunter of the African savanna. Many people think hyenas only eat leftovers, but in East and Southern Africa they catch most of their own food. They live in big clans led by females, and they whoop, groan and 'giggle' to talk.
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 Humpback anglerfish The humpback anglerfish is a small, round, black fish of the deep, dark ocean. A long spine on the female's head ends in a glowing lure, lit by tiny bacteria, which draws prey close enough to catch in her big, toothy mouth. The males are tiny, only about 3 centimeters long, and their job is to find a female.
Animal European peacock butterfly The European peacock butterfly has rusty-red wings with four big, colorful eyespots, like the spots on a peacock's tail. When a bird comes close, it flashes its eyespots and makes a hissing sound. Its black, spiny caterpillars live together on stinging nettles, and the adults sleep through the winter in hollow trees and sheds.
Country Sierra Leone Sierra Leone is a country on the Atlantic coast of West Africa. Its name comes from Portuguese words meaning Lion Mountains, after the hills around Freetown's huge natural harbor. Rainforests, rivers and mangrove swamps are home to chimpanzees and pygmy hippos, and the 2021 census counted about 7.5 million people.
Landmark The Great Sphinx The Great Sphinx at Giza, Egypt, is a lion with a human head, carved out of the solid rock about 4,500 years ago. It is about 73 meters long and 20 meters high, one of the largest sculptures in the world. Most experts think it shows the face of King Khafre.
Landmark Mycenae Mycenae, in southern Greece, was the richest and most important palace city of Bronze Age Greece, more than 3,000 years ago. Its people built huge stone walls, a palace, a gate topped with two carved lions and great round tombs. Archaeologists have found gold masks, cups and jewelry there, and clay tablets with an early form of Greek writing.
Country Honduras Honduras is a mountainous country in Central America, with the Caribbean Sea to the north and a short Pacific coast to the south. Its forests are home to jaguars and macaws, the Maya city of Copán stands in the west, and about 10.2 million people live there (official 2026 estimate).
Country Mozambique Mozambique stretches along the Indian Ocean coast of southeastern Africa. The great Zambezi River cuts through its middle, its beaches face the island of Madagascar, and parks like Gorongosa are home to elephants and lions. About 35.6 million people lived there in 2025, and Portuguese is the official language.
Animal Great white shark The great white shark is the largest of the mackerel sharks: a strong, torpedo-shaped fish with a gray back and a white belly. It hunts fish, seals and sea lions, and it is partly warm-blooded, which helps it stay active in cool water.
Natural wonder Serengeti National Park Serengeti National Park in northern Tanzania protects 14,763 square kilometers of grassy plains and woodlands. Each year more than a million wildebeest, with zebras and gazelles, travel a great loop across the Serengeti and into Kenya in search of grass and water, followed by lions and other predators.
Animal Mimic octopus The mimic octopus is a long-armed, brown-and-white octopus that lives on sandy sea floors in Southeast Asia. Scientists first filmed it in 1998 and were amazed: it changes its shape, colors and movements to look like other animals, including a flatfish, a lionfish and a sea snake.