Geckos are harmless, large-eyed, soft-bodied reptiles belonging to the family GEKKONIDAE. In Australia this family comprises 16 sub-groups containing more than 63 species which can be broadly divided into two types: ground dwellers and tree or rock dwellers.
Like snakes, geckos have no movable eyelids. Instead, a fixed transparent scale over the eye performs the same protective function as movable eyelids. Geckos are commonly seen running their long tongues over this scale; presumably to keep it clean. The gecko's eyes also have vertical pupils, typical of nocturnal reptiles.
Nearly all geckos are nocturnal, sheltering during the day under bark, rock slabs and in holes in the ground. To survive, they have developed an extraordinary variety of behavioural and physiological adaptions enabling them to live under a wide range of environmental conditions.