Geckos are small to average sized lizards that live in warm climates. They are most numerous in Southeast Asia, Africa and Australia. There are an estimated 800 or more species of gecko, belonging to the family Gekkonidae and ranging in size from 3.5 to 36 centimeters long. The largest gecko is the Tokay, growing 25 to 36 centimeters in length. The Tokay gecko is found in Malaysia.
75% of geckos are nocturnal, and have narrow, vertical pupils that block out light. All geckos, like snakes, have fused eyelids that make them unable to blink. To clean their eyeballs geckos lick them with protrusible notched tongues. Geckos vary across species in shade, shape and size. Some species can change color, allowing them to camouflage in different environments. Others can drop and subsequently regrow their tails if attacked. Common gecko species include the Leopard Gecko, the House Gecko, and the Tokay Gecko.
How do they walk on walls?
Contrary to popular myth, geckos do not have sticky webbed feet. Their ability to crawl nimbly across walls is due to thousands of tiny bristles (also called setae) on the underside of their toes. These long toes can be curled away from surfaces to loosen the hairs and allow the lizard to move freely. The scientific term for the sticky attraction between a gecko’s setae and a smooth surface (such as a wall) is Van der Waals force (named after Dutch scientist Johannes Diderik van der Waals).
The Geckos Name
Geckos have an ability that is unique among lizards – they can produce sounds. Some species emit high pitched chirps, while others produce sounds that resemble the quack of a duck or a dog’s bark. The name ‘gecko’ – originally from the Indonesian word ‘Tokek’ – mimics the call of some species. Other languages, also naming the gecko after the noise it makes, have different interpretations. In Malaysia and Singapore the gecko is called ‘cheek chak’; in the Philippines it is the ‘tuko’; in Thailand‘jing-jok’; and in Cambodia geckos are known as ‘chhin chhos’.
The Common House Gecko
Originally from Southeast Asia, the Common House Gecko or Asian Gecko was spread by ships and now resides in many parts of the world. These small lizards, about 7 centimeters in length, are found countries such as Thailand, Cambodia, Hong Kong, Japan and Australia. They range in color from pale pink or light yellow to grayish-white, sometimes appearing almost transparent. These geckos are not bad housemates, as they eat mosquitoes and spiders.
Some estimates put the number of gecko species on the planet in the thousands, with many of them yet to be discovered. In 2010 a new species of gecko was found in Cambodia’s Cardamom Mountain range, one of the least explored jungles in Asia. The new gecko, named Cnemaspis neangthyi, is olive in color with light blotches, making it extremely adept at camouflage.
With impressive coloration, distinctive sounds and extraordinary climbing capabilities, geckos are truly remarkable creatures.
Quick Facts About Geckos for Kids
- Geckos are lizards belonging to the infraorder Gekkota, found in warm climates throughout the world.
- Nocturnal species have an excellent night vision; their color vision is 350 times more sensitive than human color vision.
- Many species are well known for their specialized toe pads that enable them to climb smooth and vertical surfaces, and even cross indoor ceilings with ease.
- It was probably wiped out along with much of the native fauna of these islands in the late 19th century, when new invasive species such as rats and stoats were introduced to the country during European colonization.
- The smallest gecko, the Jaragua sphaero, is a mere 1.6 cm long and was discovered in 2001 on a small island off the coast of the Dominican Republic.
- The gecko’s mating call sounds like a shortened bird chirping which attracts males, when they are nearby.
- When shedding begins, the gecko will speed the process by detaching the loose skin from its body and eating it.
- About 60% of gecko species have adhesive toe pads; such pads have been gained and lost repeatedly over the course of gecko evolution.
- The spatula-shaped setae arranged in lamellae on gecko footpads enable attractive van der Waals’ forces between the β-keratin lamellae/setae/spatulae structures and the surface.
- These van der Waals interactions involve no fluids; in theory, a boot made of synthetic setae would adhere as easily to the surface of the International Space Station as it would to a living-room wall, although adhesion varies with humidity.
- The role of water in that system is under discussion, yet recent experiments agree that the presence of molecular water layers on the setae as well as on the surface increase the surface energy of both, therefore the energy gain in getting these surfaces in contact is enlarged, which results in an increased gecko adhesion force.
- Eublepharis macularius, the leopard gecko, is the most common gecko kept as a pet; it does not have adhesive toe pads and cannot climb the glass of a vivarium.
- Hemidactylus frenatus, the Common house gecko, thrives around man and human habitation structures in the tropics and subtropics worldwide.
- Hemidactylus garnotii, the Indo-Pacific gecko, is found in houses throughout the tropics, and has become an invasive species of concern in Floridaand Georgia in the US.
- Hemidactylus mabouia, the Tropical house gecko, Afro-American house gecko or Cosmopolitan house gecko, is a species of house gecko native to sub-Saharan Africa and also currently found in North, Central and South America and the Caribbean.
- Rhacodactylus ciliatus, the crested gecko, was believed extinct until rediscovered in 1994, and is gaining popularity as a pet.