Chamaeleonid

Chamaeleonids have carried the trend further; nearly all species have lost or greatly reduced vomeronasal and olfactory systems [Parsons, 1970; Gabe and Saint Girons, 1976] and rely, instead, on vision.

Iguanids apparently were isolated in Africa by epicontinental seas and gave rise to chamaeleonids in the west and agamids in the east; the scincomorphs radiated in Laurussia, giving rise to the teiids in North America and lacertids in Europe.

Chamaeleonids’ ears have simplified over time, and they are not visible externally, being covered with skin and scales. Unlike other lizards, chamaeleonids possess neither an exterior aperture nor a tympanic membrane, but they share some skeletal and fluid structure similarities with snakes.