Physical differences between alligators and crocodiles include their skin color, the shapes of their jaws and their teeth placement. Other differences include their environments and aggressiveness.
Alligators usually have darker skin than crocodiles. Alligators have wide, round jaws with U-shaped snouts. Crocodiles have narrow, pointed jaws with V-shaped snouts. Alligator jaws are more powerful than crocodile jaws and allow them to eat prey with hard shells, while crocodile jaws are designed for a broader range of prey. The alligator's bottom teeth can't be seen when its mouth is closed because its upper jaw is wider than its lower jaw. The crocodile's upper and lower jaws are equal in size, and its prominent fourth tooth on the lower jaw fits outside the upper jaw when its mouth is closed. Alligators live in freshwater habitats, while crocodiles live in saltwater habitats because a gland in their tongues gets rid of salt. Wild alligators only live in the United States and China. Wild crocodiles live around the world. Crocodiles tend to be more aggressive. There are different species of alligators and crocodiles. Each species is unique, so there are some exceptions to these common differences. One example is the Indian mugger crocodile, which has a wide jaw similar to an alligator but also has the prominent fourth tooth of a crocodile.