lizard

This page is about 'Lizards', the order of reptile. For alternate uses, see Lizard (disambiguation)

Many, see text. Lizards are reptiles of the order Squamata, which they share with the snakes (Ophidians). They are usually four-legged, with external ear openings and movable eyelids. Species range in adult length from a few centimeters (some Caribbean geckos) to nearly three meters (Komodo dragons). Some lizard species called "glass snakes" or "glass lizards" have no functional legs, though there are some vestigial skeletal leg structures. They are distinguished from true snakes by the presence of eyelids and ears. Many lizards can change color in response to their environments or in times of stress. The most familiar example is the chameleon, but more subtle color changes occur in other lizard species as well (most notably the anole, also known as the "house chameleon" or "chamele"). Lizards typically feed on insects or rodents. A few species are omniverous or herbiverous, such as the iguana. Iguanas are unable to properly digest animal protein. Only two lizard species are venomous: the Mexican beaded lizard and the Gila monster, both of which live in northern Mexico and the southwest United States. They are typically not hazardous to humans as their poison is introduced slowly by chewing, rather than injected as with most poisonous snakes. Other small lizards are harmless to humans (most species native to North America, for example, are incapable of drawing blood with their bites). Most lizards lay eggs, though a few species are capable of live birth. Many are also capable of regeneration of lost limbs, such as tails. Lizards in the Scincomorpha family, which include skinks (such as the blue-tailed skink), often have shiny, iridescent scales that appear moist. But like all other lizards, they are dry-skinned, generally preferring to avoid water (though all lizards are able to swim if needed).