what's the difference between alligators and crocodiles?
Crocodiles have long, pointed snouts, shaped like a 'V,' whereas alligators have more rounded snouts, like the letter 'U' [source: San Diego Zoo ]. The broader alligator jaw is stronger -- designed to withstand the pressure of cracking down on hard-shelled prey like turtles that are abundant in its particular habitat.
Alligators and crocodiles are in the same reptile subgroup. They mostly live in tropical or semitropical regions. Alligators are mostly found in the southern United States and the crocodiles in Africa, India, South America, and southern United States. They are among the largest reptiles. Their bodies are covered with scales and they have webbed toes. They live in swamps and along the banks of rivers.
When an alligator flashes a closed-mouth smile, all you can see are its downward-pointing top teeth. Crocodiles have toothier smiles: Since both jaws are roughly the same sizes, their upper and lower teeth interlock when they shut their mouths, giving you an eyeful of both upper and lower teeth.