There are an estimated 400 to 600 species of gecko lizards, and their natural habitats range from wet climates such as tropical rainforests and marshes to dry ones of deserts and grasslands. They are members of the Gekkonidae family of lizards, and, as cold-blooded creatures, are restricted to climates where the temperature is not extremely hot or cold, as they cannot regulate their body temperature. One of the advantages to being cold-blooded, however, is that less energy is required to sustain life, and this makes it possible for gecko habitats to include environments where food sources may be somewhat scarce.
Geckos are popular as small pets, since many species such as the Tokay gecko don't grow larger than 14 inches (36 centimeters) in length. They are also the only known lizard to have an ability to make vocalizations. The sounds they utter can often appear to be similar to the word gecko. Their popularity as pet lizards has spread them to all regions of the world populated by people, and accidental releases of breeding pairs into the wild has allowed them to establish gecko habitats in regions to which they otherwise weren't native.
Two unique traits of exotic pets such as geckos have allowed them to establish wild gecko habitats in urban areas. They are nocturnal creatures with no eyelids, which gives them the trait of seeking out shadowy and hidden areas to live, which keeps them out of the way of people. Smaller species of geckos also have toe pads on their feet that allow them to cling to nearly any vertical or horizontal surface. In warm climates, species such as the tiny House Gecko, a genus of 90 similar types of small lizards about 1 inch in length (2.54 centimeters), are welcomed into homes as harmless wild creatures. Their ability to control the mosquito, cockroach, and other insect populations has established enduring gecko habitats for them in many tropical cities and urban landscapes.
Geckos are thought to have originated in Southeast Asia and the western Pacific. Their spread around the world now includes gecko habitats even on many isolated islands. Unlike many small animals that have short lifespans, a gecko can live for up to 15 years in the wild. They tend to be very mobile creatures, and this, along with their ability to easily coexist with people, has led to gecko habitats being established in virtually every warm climate that's available.