Chameleons do not have external ears or a tympanic membrane, but they do have internal ears as well as degenerated middle ears. They do not hear well but they can detect low frequency sounds.
The horns on a chameleon are made up of ringlike segments of inner bone covered by a hard keratin-like skin.
The word Bradypodion comes from the latin “bradus podos” or slow foot.
The largest chameleon species by weight is Calumma parsonii (Parson’s Chameleon).
The oldest known chameleon fossil is from the extinct species Chamaeleo caroliquarti. It was found in Europe and is 26 million years old.
Chameleons change color by rearranging a lattice of nanocrystals in one of their top layers of skin cells called iridophores. Chameleons can then stretch this layer, broadening the nanocrystalline lattice, thereby causing it to reflect a different wavelength of light.
Chamaeleo namaquensis is found in the desert of Namibia. To cool off it will sometimes bury itself in the sand.
Chameleon fossils have been found in central Europe and China, indicating they were once much more widespread than they are now.
Many chameleon species have a bright red, orange or yellow mouth. This conspicuous interior when displayed is used as a defense against predators.
Furcifer labordi (Labord’s Chameleon) has the shortest lifespan of only 4-5 months. It also has the shortest lifespan of any tetrapod!