There are differences in physical characteristics between the two species. When an alligator's jaw is closed, the fourth tooth on the lower jaw is not visible. The tooth is visible when a crocodile's jaw is closed. The American alligator has a short, broad snout. The American crocodile has a longer, more slender snout.
Special adaptations allow alligators to be skilled hunters in their watery domain.
Their eyes and nose are set high on the head so they can see and breathe while the rest of their body is hidden beneath the water's surface. The alligator's ears and nose close automatically when it submerges. A special throat valve allows alligators to feed while underwater without the risk of drowning. In addition, alligators have a large, muscular tail that helps propel them through the water. Alligators are carnivores.