Alligator

The alligator is a large reptile that lives in rivers, swamps, and lakes. It has a long body, four short legs, a thick tail, and a wide, rounded snout filled with sharp teeth. There are only two kinds of alligators in the world. The American alligator lives in the southeastern United States. The Chinese alligator lives in a small area along the Yangtze River in China.

American alligators are much bigger. A full-grown male can reach 14 feet long and weigh up to 1,000 pounds, about the weight of a grand piano. Chinese alligators rarely grow past 7 feet. Both kinds have dark, bumpy skin covered in bony plates called scutes, which work like built-in armor.

People often mix up alligators and crocodiles. The easiest way to tell them apart is by the snout. An alligator's snout is wide and shaped like a U. A crocodile's snout is narrow and shaped like a V. When an alligator closes its mouth, its teeth tuck inside. When a crocodile closes its mouth, some of its bottom teeth still stick out.

Alligators are excellent hunters. They are cold-blooded, so they spend much of the day resting in the sun to warm up. At night, they hunt fish, turtles, birds, and small mammals. An alligator can stay underwater for up to an hour by slowing its heartbeat to just a few beats per minute. When prey comes close, it lunges with a bite force of about 2,900 pounds per square inch. That is one of the strongest bites of any animal alive.

Mother alligators build large nests out of mud and plants. A female lays 20 to 50 eggs and guards them for about two months. She even carries her newly hatched babies to the water in her mouth. For a fierce predator, she is a surprisingly careful parent.

The American alligator was once close to extinction. Hunters killed millions of them for their skins, and by the 1960s very few were left. In 1967, the United States made it illegal to hunt them. The species recovered so well that today more than 1 million alligators live in the wild. The Chinese alligator, however, is still critically endangered. Fewer than 150 remain in the wild, though zoos and breeding programs are working to save them.

Alligators have been on Earth for a very long time. Their ancestors swam in the same swamps as the dinosaurs, more than 80 million years ago.