Biology and Evolution of Crocodylians

Crocodiles, alligators, caimans, and gharials--the Crocodylia, known collectively as crocodylians (or crocodilians)--are the world's largest living reptiles. The largest of them, probably the estuarine or saltwater crocodile, Crocodylus porosus , can grow to almost twenty feet and weigh more than two thousand pounds. Crocodylians are creatures of great contrast.