Crocodiles are large aquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia.
Crocodiles tend to congregate in freshwater habitats like rivers, lakes, wetlands and sometimes in brackish water. They mostly feed on vertebrates like fish, reptiles, and mammals.

Crocodiles are among the more biologically complex reptiles despite their prehistoric look. Unlike other reptiles they have a four-chambered heart, diaphragm and cerebral cortex. They live an aquatic and predatory lifestyle. A crocodile’s physical traits allow it to be a successful predator. They have a streamlined body that enables them to be fast swimmers. They also tuck their feet to their sides while swimming, which makes the animal even faster, by decreasing water resistance. Their hind feet are webbed, this allows them to make fast turns and sudden moves in the water. Webbed feet are an advantage in shallower water where the animals sometimes move around by walking. Crocodiles are very fast over short distances, even out of water. They have one of the strongest bite of any animal, possessing extremely powerful jaws capable of biting down with immense force. Crocodiles have more than 5,000 punds of bite force. They have sharp teeth for tearing and holding onto flesh, but cannot open their mouth if it is held closed since the jaws are opened by a very weak set of muscles. Since crocodiles feed by grabbing and holding onto their prey, they have powerful muscles that close the jaws and hold them shut. The larger species of crocodiles can be very dangerous to humans.