Chameleons are lizards distinguished by their zygodactylous feet, their separately mobile and stereoscopic eyes, their very long, highly modified, and rapidly extrudable tongues, their swaying gait, the possession by many of a prehensile tail, crests or horns on their distinctively shaped heads, and the ability of some to change color.
One new chameleon was found on Nosy Hara, an islet off the coast of Madagascar. Named Brookesia micra, it is the smallest of the four species. Juveniles are small enough to stand on the head of a match.
[In the year 2011,] four new species of chameleons, each just tens of millimeters in length, have been discovered on the island of Madagascar. They are among the smallest reptiles in the world.
During courtship, a male chameleon adopts his flashiest colors and bobs his head repeatedly to signal to a prospective mate or to warn off a rival suitor. A startled chameleon may suddenly turn black with anger or exhibit a pattern of spots and stripes- sometimes in less than a minute.
When a chameleon changes colors, pigment-bearing cells (called chromatophores) beneath the lizard's transparent skin either expand or shrink. These cells, which contain red and yellow pigment, are modified when other cells, which reflect blue and white or contain dark-brown melanin, mix or mask the brightly colored cells and thus darken their hues.
Chameleons are diurnal and primarily insectivorous, although birds have been recorded in the diets of some larger species. They can extend their tongues almost the entire length of their body, making their hunting behavior an impressive display. Chameleons exhibit a distinct locomotion in which they slowly rock back and forth between each step taken.
Chameleons are well known to most people, easily recognizable by their body shape, independently moving eyes, paw-like hands and feet, and ability to change color rapidly. Most researchers identify two subfamilies of chameleons, containing 4-6 genera, and more than 150 species.
Three genera (Brookesia, Calumma and Furcifer) are found almost exclusively in Madagascar, with a few species of Furcifer also on neighboring Indian Ocean islands. The genus Bradypodion is endemic to South Africa, and Rhampholeon and Rieppeleon are found in East, Central, and southern Africa.
Chameleons are not found worldwide, but have a distribution that is restricted mainly to Madagascar, Africa, and some neighboring islands (e.g. Comoros, Mauritius, Seychelles and Zanzibar), as well as the extreme southern fringes of Europe, the Arabian Peninsula and India. There are approximately 150 to 160 species, which can be arranged into nine groupings (genera) based both on morphological and genetic characteristics.
Only a few species of chameleons are bred with any degree of regularity in captivity. Among those are the veiled, Jackson's, and panther chameleons. Most of the other available species are collected from the wild.
All chameleons are initially of Old World distribution, but one or two species have escaped from captivity and can now be found in Hawaii, California, and Florida. Despite the frequency with which chameleons appear in the marketplace, as a captive these solitary lizards require a dedicated regimen of daily care tailored to a particular species.