The name alligator comes from "el lagarto" meaning, "the lizard." Alligators are part of the crocodilians, which appeared 80 million years ago during the Cretaceous period, near the end of the Mesozoic era. Crocodilians are from a group called, Crocodyloformes, who appeared 245 million years ago during the Triassic period. Temperatures inside the alligator nest can determine the sex of the young. Eggs incubated over 96 degrees produce males, from 86 degrees and below, females are produced and temperatures in between produce both sexes.