Some snakes and lizards retain their eggs and give birth to live young.
Reptiles are cold-blooded, and their skin is usually covered with scales.
Reptiles date back over 300 million years. Many extinct forms are known, including the orders Pterosauria, Plesiosauria, Ichthyosauria, and Dinosauria. The order Rhynchocephalia has one surviving species, the lizardlike tuatara of New Zealand. A four-year study of rainforest in eastern Madagascar revealed 26 new reptile species 1995.