Chameleons

Chameleons belong to the family Chamaeleonidae which are a family in the order Squamata. They are a type of lizards and, just like all lizards, they are reptiles. The word chameleon is derived from the Latin word chameleo. Chameleo in turn is the Latin version of the ancient Greek word χαμαιλέων (khamaileon). The word χαμαιλέων (khamaileon) consists of two parts: χαμαί (khamai) which means on the earth/ground and λέων (leon) which means lion. Chameleon does in other words mean ground lion or lion on the ground.
Chameleons are easy to identify on their parrot like feet, their stereoscopic eyes (independent from each other), their long tongues, their characteristic walk and the crest or horns found on the head. Their characteristic walk consists of swaying forward and backward when they wish to get somewhere. Some theorize that this is to better mimic the vegetation they live in.
There are about 160 different know species of chameleons. Their native habitat stretches from Africa and southern Europe (Spain and Portugal) to eastern Asia, including Sri Lanka. Most species are found in Africa, including the island of Madagascar. Today they can be found in other places as well such as Hawaii and Florida in the United States after being introduced by man. Chameleons inhabit a wide variety of different environments ranging from tropical rainforests to deserts.
The largest species of chameleon in the world is Furcifer oustaleti. Male Furcifer oustaleti chameleons can grow to be 68.5 centimetres (27 inches) in length. The smallest species of chameleon in the world is the Brookesia minima which grows to a mere 3.4 centimetres (1.3 inches).
Most chameleons prey on insects but some of the largest species will also hunt birds and other lizards. A small number of chameleons eat vegetables as a part of their diet. Chameleons have a high vitamin requirement and it is important to supplement their diet with a lot of vitamins when keeping them in captivity.
Most chameleons lay eggs but some species give birth to live young after a gestation period of 5-6 months. Egg laying species lay their eggs in a hole in the ground after a gestation period of 3-6 weeks. The holes in the ground have different depths in different species. Once the female have deposited all the eggs she closes the hole. The amount of eggs varies dramatically between different species. Some small species only lay 2-4 eggs while other species can lay up to a hundred eggs. The incubation period of different species also varies dramatically and can be anything from 4 and 24 months. Most species incubate for 4-12 months.
Chameleons are famous for being able to change colour but this is an ability that only some of the chameleons posses. They can mimic most colours including pink which a popular myth claims that they can’t change into. The chameleons use their colour changing ability not just to hide themselves but also to lure females and communicate with other chameleons.
Chameleons get their ability to change colour from a special type of cells called chromatophores that are placed between a transparent lower of outer skin and the inner skin. The cells in the outer layer are called xanthophores and erythrophores. These layers contain yellow and red colour. Below these is another layer of cells called iridophores or guanophores, containing the collarless crystalline substance guanine. This layer is used to reflect several colours including blue. Below that layer is a dark layer of mellianophoripeidess containing melanin. Which colours it chooses to reflect in the first two layers decide the overall colouration of the animal. If it reflects blue and yellow the chameleon looks green. The third layer decides how dark the colour is.