Final answer:
Chameleons are a type of lizard with the unique ability to change color, utilized for camouflage and social signaling. They have chromatophores in their skin to facilitate this change, and share features with snakes.
Step-by-step explanation:
Chameleons are a fascinating group of lizards known for their ability to change color. This ability is not just for camouflage purposes; it also plays a critical role in social signaling among these reptiles. Chameleons possess specialized skin cells known as chromatophores, which contain different pigments that can be redistributed to alter their skin coloration.
In addition to their color-changing prowess, chameleons share several features with snakes, another group of reptiles. Both have scales covering their skin and are cold-blooded, but chameleons are set apart by their unique features such as movable eyes, horns, and a distinctive head shape. Unlike snakes, chameleons have the ability to focus their vision by altering the shape of their lens, providing them with excellent color vision.
Across the approximately 6,000 species of lizards, chameleons are classified based on their distinct characteristics which include their parrot-like feet, stereoscopic eyes, and extrudable tongues, as well as the shape of their heads with crests or horns. With about 160 species of chameleons identified, their classification takes into account their physical and behavioral traits, distinguishing them from other lizard species.