chameleon (kəmē´lēən, –mēl´yən), small- to medium-sized lizard of the family Chamaeleonidae. More than 150 species are found in sub-Saharan Africa, with a few in S Europe and S Asia. The so-called common chameleon, Chamaeleo chamaeleon, is found around the Mediterranean.
Chameleons have laterally flattened bodies and bulging, independently rotating eyes. They are variously ornamented with crests, horns, and spines. The toes are united into one bunch on either side of the foot, forming a pair of grasping tongs. Chameleons feed on small animals, chiefly insects, and they are unique among lizards in possessing very long, sticky tongues with which they capture their prey. Typical chameleons (members of the genus Chamaeleo) are arboreal and have long, prehensile tails. They move very slowly, with a rocking movement, grasping a branch with feet and tail.
The changes in skin color, seen in certain other lizards as well, are under hormonal and nervous control. They are not affected by the color of the background but by stimuli such as light, temperature, and emotion, and are used most dramatically in contests between rivals and to attract a mate. However, the shades of brown, gray, and green assumed by chameleons do generally blend with the forest surroundings.
The American chameleon, or anole (Anolis carolinensis), is not a true chameleon, but a small lizard of the iguana family, found in the SE United States and noted for its color changes. True chameleons are classified in the phylum Chordata, subphylum Vertebrata, class Reptilia, order Squamata, family Chamaeleonidae.