The slits on their heads lead to a well-developed inner ear, and the slits close up when they dive to keep water out. Both males and females have an "armoured" body with a muscular flat tail, used in propelling the animal forward while swimming.
American alligators are usually solitary creatures found in freshwater swamps, marshes, rivers, and lakes.
Nostrils at the end of the snout allow for breathing while the alligator is otherwise fully submerged beneath the water's surface.