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The Dominican Anole or Eyed Anole (''Anolis oculatus'') is a species of anole lizard. It is endemic to the Caribbean island of Dominica, where it is found in most environments. It is distributed in four main population groups on the island, which were initially described as subspecies and now are recognized as ecotypes. It has a very diverse morphology between these populations, with a ground color that ranges from pale tan or yellow to deep green or brown. It also has patterned markings that range from light-colored speckling to complex marbled patterns, and some populations also have large black-ringed "eye" spots on their flanks. This diversity is the product of adaptation to different ecological conditions found within Dominica, which has made it the subject of numerous studies. The Dominican Anole spends much of the time in trees but mainly hunts on the ground. Insects make up the bulk of its prey, with soft-bodied invertebrates and small vertebrates hunted less frequently. Long-living and late maturing for anoles, the Dominican Anole can usually breed from around two to three months of age. Females lay eggs, and breeding can occur at any time of year. Clutches number one or sometimes two eggs and are laid under rocks or leaves on the ground. Although presently widespread and common on Dominica, it faces competition from the Puerto Rican Crested Anole, an invasive species which has begun to supplant it in part of its range. ==History and taxonomy== The Dominican Anole is locally known as the zandoli, or tree lizard.〔; . Also spelled "zanndoli".〕 The indigenous Caribs considered its presence in their home to be a sign of "good spirits".〔According to Honychurch.〕 American paleontologist and herpetologist Edward Drinker Cope first gave a cursory description of the species, which he named ''Anolis alliaceus'', on the basis of 16 specimens owned by the British Museum that lacked locality data.〔. This history is also recounted in .〕 He later separately described ''Xiphosurus oculatus'' in 1879, from 13 specimens in the U.S. National Museum (now the Smithsonian); the name ''oculatus'' (Latin, "eyed") refers to its distinctive lateral spots.〔.〕 The two taxa were finally described as one species, ''Anolis oculatus'', in 1888, by the German-British zoologist Albert Günther.〔.〕 Because of its morphological variation, however, confusion remained as to whether the Dominican Anole comprised multiple species or only one.〔Garth Underwood wrote in 1959, regarding the widely varying specimens he examined, that "()fter two visits to the island and examination of more than sixty preserved specimens I remain uncertain about the situation in Dominica...Clearly Dominica will require further careful examination." .〕 This was resolved by the work of American herpetologist James D. Lazell, Jr. In 1959, he collected over 500 specimens from thirty localities on Dominica, which he reached primarily on foot or on horseback due to the inadequate road system.〔; he recounts the difficulties of his 1959 journeys in .〕 From this, he concluded that it was a single species, and in 1962 provided the first coherent account of its variation, organized by different regional populations that he classified as four subspecies: ''A. o. oculatus'', found along the southwestern coastal area, with a holotype from the capital of Roseau (most closely corresponding to the original type described by Cope); ''A. o. cabritensis'', along the northwest coast, with a holotype from the Cabrits peninsula; ''A. o. montanus'', in central, high elevation rain forest, with a holotype from Fresh Water Lake; and ''A. o. winstoni'', along the northeast coast, with a holotype from the village of Woodford Hill.〔See ("Lazell (1962, 1972) was the first to provide a coherent account of the geographic variation in morphology"). Detailed descriptions of the coloration and markings of each described subspecies, along with type specimen data, is provided in , with a Table of Diagnostic Characters at p. 475 cataloging variations in throat fan (dewlap) color, white dorsal spotting, black pigment areas, ground color, venter color, tail crest, and maximum SVL. The SVL figures should be considered inaccurate or incomplete, however, as Lazell later noted that he had incorrectly omitted larger specimens. See .〕 These first descriptions applied only to males, however, and omitted certain morphological features such as scale variation.〔See , describing the errors and inadequacies in his 1962 paper.〕 Lazell returned to Dominica in 1966 to collect new specimens, and in 1972 supplemented his original descriptions, including color illustrations of sexual dimorphism among the types.〔.〕 Lazell noted that the subspecies he described corresponded with the "strikingly different" ecological zones on Dominica, which result from the extreme elevations on the small island interacting with prevailing winds to produce varying rainfall and vegetation.〔; .〕 Later morphological and molecular studies determined, however, that there was no interruption to gene flow between the different populations, but instead clinal variation adaptive to local ecological factors.〔; ; .〕 Researchers have, therefore, determined that there is no basis for the use of subspecies nomenclature.〔 "Consequently, meaningful definition of boundaries between subspecies is difficult".〕 The former subspecies are now described as ecotypes based on their geographic range: the South Caribbean ecotype corresponds to the former ''A. o. oculatus''; North Caribbean ecotype to ''A. o. cabritensis''; Montane ecotype to ''A. o. montanus''; and Atlantic ecotype to ''A. o. winstoni.''〔See for photographic comparisons of these ecotypes for both males and females.〕 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「Dominican Anole」の詳細全文を読む スポンサード リンク
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