Crocodilians (crocodiles, alligators, and caimans) first appeared 95 million years ago. Crocodiles are large semiaquatic reptiles. They live near lakes, rivers, and wetlands in the tropic regions of Africa, Asia, the Americas, and Australia. There are 16 species of varying sizes – from the dwarf crocodile (1.5 meters) to the saltwater crocodile (7 meters). Crocodiles are ectothermic (cold-blooded) animals and rely on environmental heat sources. They absorb heat through their skin while basking in the sun and cool down by seeking shade. They also release heat through their mouths and can often be seen sleeping with open mouths, panting like a dog. To “cry crocodile tears” is to fake sadness or grief. Crocodiles do weep but not over their victims. They produce tears to lubricate their eyes, which can also be triggered while eating.