One of the remarkable things about this scaly skin is that it can change colour. Many reptiles turn a darker colour when basking in order to absorb the sun's warmth better. Chameleons can change colour to match their background and avoid being spotted by predators. Unlike mammals, reptiles grow all through their lives, but their skin does not. Every now and then, they must shed or slough their skin to reveal a soft new one underneath.
Snakes slough off all the old skin in a single piece.
Although most live in the warm tropics and subtropics, lizards inhabit a wide range of different environments. There are land lizards, tree lizards, water lizards and even flying lizards. The largest lizard of all is the Komodo dragon, which grows up to 3m long. The smallest are geckos just a few centimetres long. Like most reptiles, lizards are hunters and can move very quickly.