Chameleons (Chamaeleonidae) form a group of lizards that includes about 160 species. Chameleons are most noted for their unique feet, stereoscopic eyes and lighting-fast tongues. Chameleons are arboreal creatures and consequently their feet are specially adapted for grasping branches and twigs. They have five toes on each foot which are fused into two bundles (one of two toes, the other of three toes). This foot structure, referred to as zygodactyly, offers chameleons a strong grip.
Chameleons have cryptic coloration and are capable of changing their color and pattern to blend with their surroundings. They accomplish this color change by contracting or expanding cells in their skin that contain pigments. Their body shape is arched and leaf-like in shape.
Chameleons are carnivores. They feed on insects and spiders. Larger species of chameleons also feed on small vertebrates such as mammals and birds. To catch prey, chameleons launch their long tongue from their mouth using specialized muscles. The tip of the tongue is equipped with a suction-cup-like structure which is coated in mucus.
Chameleons are lizards
, a group of reptiles
that (in addition to chameleons) includes iguanas, chisel-teeth lizards, geckos
, night lizards, blind lizards, skinks, anguids, beaded lizards and many others. There are approximately 160 species of chameleons that are divided into about 9 subgroups (genera).
The oldest known chameleon from the fossil record is Chamaeleo caroliquarti a species that lived about 26 million years ago.