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| image = Phelsuma_l._laticauda.jpg | image_caption = Gold dust day gecko | regnum = Animalia | phylum = Chordata | classis = Reptilia | ordo = Squamata | subordo = Scleroglossa | infraordo = Gekkota | infraordo_authority = Cuvier, 1817 | subdivision_ranks = Families | subdivision = Pygopodidae Carphodactylidae Diplodactylidae Eublepharidae Sphaerodactylidae Gekkonidae Phyllodactylidae }} Geckos are lizards belonging to the infraorder Gekkota, found in warm climates throughout the world. They range from 1.6 to 60 cm. Most geckos cannot blink, but they often lick their eyes to keep them clean and moist. They have a fixed lens within each iris that enlarges in darkness to let in more light. Geckos are unique among lizards in their vocalizations. They use chirping sounds in social interactions with other geckos. They are the most species-rich group of lizards, with about 1,500 different species worldwide.〔http://reptile-database.reptarium.cz/advanced_search?taxon=gecko&submit=Search Geckos in the Reptile Database〕 The New Latin ''gekko'' and English "gecko" stem from the Indonesian-Malay ''gēkoq'', which is imitative of the sound the animals make.〔(gecko, n. ) Oxford English Dictionary Second edition, 1989; online version September 2011. Accessed 29 October 2011. Earlier version first published in New English Dictionary, 1898.〕 All geckos, excluding the Eublepharidae family, lack eyelids and instead have a transparent membrane, which they lick to clean. Nocturnal species have an excellent night vision; their color vision is 350 times more sensitive than human color vision. The nocturnal geckos evolved from diurnal species which had lost the eye rods. The gecko eye therefore modified its cones that increased in size into different types both single and double. Three different photopigments have been retained and are sensitive to UV, blue, and green. They also use a multifocal optical system that allows them to generate a sharp image for at least two different depths.〔(The pupils and optical systems of gecko eyes )〕〔(Gecko-inspired multifocal contact lenses, cameras on the anvil )〕 Most gecko species can lose their tails in defense, a process called autotomy. 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. Geckos are well-known to people who live in warm regions of the world, where several species of geckos make their home inside human habitations. These (for example the house gecko) become part of the indoor menagerie and are often welcomed, as they feed on insects, including moths and mosquitoes. Unlike most lizards, geckos are usually nocturnal. The largest species, the kawekaweau, is only known from a single, stuffed specimen found in the basement of a museum in Marseille, France. This gecko was 60 cm (24 in) long and it was likely endemic to New Zealand, where it lived in native forests. 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. ==Common traits== Geckos occur in various patterns and colors, and are among the most colorful lizards in the world. Some species can change colour and may be lighter in colour at night. Some species are parthenogenic, which means the female is capable of reproducing without copulating with a male. This improves the gecko's ability to spread to new islands. However, in a situation where a single female gecko populates an entire island, the island will suffer from a lack of genetic variation within the geckos that inhabit it. The gecko's mating call sounds like a shortened bird chirping which attracts males, when they are nearby. Like other reptiles, geckos are ectothermic,〔Girons, Hubert. "Thermoregulation in Reptiles with Special Reference to the Tuatara and Its Ecophysiology" Tuatara: Volume 24, Issue 2, August 1980. Victoria University of Wellington Library, August 1980. Web. May 31, 2014. http://nzetc.victoria.ac.nz/tm/scholarly/tei-Bio24Tuat02-t1-body-d2.html.〕 producing very little metabolic heat. Essentially a gecko's body temperature is dependent on its environment. Also, in order to accomplish their main functions—such as locomotion, feeding, reproduction, etc.—geckos must have a relatively elevated temperature.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「gecko」の詳細全文を読む スポンサード リンク
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