ReptilesReptiles are cold blooded animals, covered with scales, and mostly lay eggs. Some
reptiles eat plants, some eat animals and some eat both. Reptiles are
tetrapod vertebrates, meaning they have four limbs or, like snakes, they
descended from four limbed ancestors. They usually have limited means
of maintaining a constant body temperature and rely on external sources
of heat. Being cold blooded requires far less fuel to function.A crocodile needs a fraction of the food a lion of the same weight
needs, and can live half a year without eating. Due to their slow
metabolism, reptiles can do well in areas where food sources are too low
for most mammals and birds to live.
Four major groups of reptiles include crocodilians, snakes, turtles, lizards and ttuatara – a lizard-like reptile that is the only surviving member of an order which flourished around 200 million years ago. The study of reptiles, historically combined with that of amphibians, is called herpetology.