Why do reptiles have scaly skin?

Most people know that snakes and lizards are reptiles. Turtles and Crocodiles are also reptiles but frogs (which are amphibians) are not. Reptiles are vertebrates that breath air and depend on outside sources for body heat.

The most obvious feature of reptiles is their non-porous, scaly skin. This helps to greatly reduce water loss from the body; as a result they do not need constant access to water.

Some reptiles get all their liquid requirements from the prey they eat. This ability of reptiles to conserve body fluids means that they are able to successful y inhabit very dry and arid parts of Australia.