There are only two species of alligator in the world, the American and Chinese alligator. There regions to clash such as the American alligator and crocodile. The Caiman are also in the Alligator family, and the Black Caiman can get to be 18 feet long 1500-200OIbs. Alligator -have short broad snout -when the mouth is closed because lower jaw is narrower no bottom teeth are visible. -Alligators are a blackish color. -They live in fresh and brackish water, but prefer fresh. Crocodile -Have a longer narrower snout -top and bottom jaw are nearly the same width so teeth on the top and bottom are visible along the whole jaw line. -Crocodiles are a lighter olive brown color -They live in fresh water and brackish water, though the saltwater Crocodile can live in salt water.