What do you know about chameleons?

Class: Reptilia (Reptiles)

Order: Squamata

Family: Chamaeleonidae

Genera: 6

Species: 158

Length: longest— Madagascan chameleon, or Oustalet's chameleon Furcifer oustaleti, up to 23 inches (60 centimeters) long; shortest— pygmy leaf chameleon Brookesia minima, 0.9 inches (2.54 centimeters)

Life span: Unknown in wild; over 10 years in zoos

Gestation/Incubation: For live young, 4 to 6 months; for egg incubation, 4 to 24 months, depending on species.

Number of young at birth/number of eggs laid: Most chameleons are egg layers, with small species laying 2 to 4 eggs and large species laying 80 to 100 eggs. Some species give live birth to 8 to 30 young.

Age of maturity: 1 to 2 years, depending on species

Chameleons vary greatly in size and body structure, with maximum total length varying from 3.4 cm (1.3 in.) in Brookesia minima (one of the world's smallest reptiles, possibly only surpassed by geckos from the genus Sphaerodactylus) to 68.5 cm (27 in.) in the male Furcifer oustaleti.[2] Many have head or facial ornamentation, such as nasal protrusions, or horn-like projections in the case of Chamaeleo jacksonii, or large crests on top of their head, like Chamaeleo calyptratus. Many species are sexually dimorphic, and males are typically much more ornamented than the female chameleons.

Chameleon species have in common their foot structure, eyes, lack of ears, and tongues.

Oustalet's Chameleon, Ambalavao, MadagascarChameleons are didactyl: on each foot the five toes are fused into a group of two and a group of three, giving the foot a tongs-like appearance. These specialized feet allow chameleons to grip tightly to narrow branches. Each toe is equipped with a sharp claw to gain traction on surfaces such as bark when climbing. The claws make it easy to see how many toes are fused into each part of the foot — two toes on the outside of each front foot and three on the inside.

Their eyes are the most distinctive among the reptiles. The upper and lower eyelids are joined, with only a pinhole large enough for the pupil to see through. They can rotate and focus separately to observe two different objects simultaneously. It in effect gives them a full 360-degree arc of vision around their body. When prey is located, both eyes can be focused in the same direction, giving sharp stereoscopic vision and depth perception. They have very good eyesight for reptiles, letting them see small insects from a long (5-10 cm) distance.