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Distribution And Habitat, Physiology And Reproduction, Defensive Behavior

Geckos are small night-lizards found in the tropics and subtropics, and number more than 650 species in the A parachute gecko (Ptychozoon kuhli). Photograph by Tom McHugh. The National Audubon Society Collection/Photo Researchers, Inc. Reproduced by permission. family Gekkonidae, divided into four subfamilies (the Diplodactylinae, the Gekkoninae, the Sphaerodactylinae, and the Eublepharinae). Only the Eublepharinae have eyelids, while members of the other three subfamilies have transparent scales protecting their eyes.

Geckos are small lizards, ranging in length from less than 2 in (5 cm), to seldom more than 1 ft (30 cm). Geckos are primarily insectivorous and nocturnal, and are unique in that they are the only lizards with a true voice. Depending on the species, geckos utter anything from a soft, high-pitched squeak to a loud bark. The name gecko arose as an attempt by humans to mimic the sound made by a common North African species ( Gekko gekko). Geckos have a soft, scaly, often transparent skin which readily tears away, allowing the little creature to escape the jaws or beak of a predator. Special toe pads enable geckos to walk upside down across rocks, on ceilings, and up the walls of city skyscrapers. Geckos are thought to have originated in Southeast Asia and the western Pacific, but are now found in large numbers in the warmer parts of every continent, and even on isolated islands around the world. Geckos make popular house pets, since they are harmless, relatively unafraid of humans, and provide effective and natural control of insect pests such as the cockroach. Geckos may live as long as 15 years in their natural environment, but seldom that long in captivity.

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