Cold-blooded, thick-skinned, and egg-laying, the ancient order of crocodilians, which includes crocodiles and alligators, garners wary respect from most people. Appearing about 230 million years ago, the hearty crocodilians have survived nearly every earthly scenario, outliving dinosaurs, ice ages, and more, yet they have changed very little over time. Unfortunately, human activities are proving to be their most formidable challenge yet. Of the 23 species of crocodilians, 7 are critically endangered, including the African dwarf crocodile, and nearly all are at risk in some part of their range. These crocodiles are native to the dense, swampy rain forests of western Africa, where their small size makes it easier to maneuver and find food.