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The okapi (''Okapia johnstoni''), is a giraffid artiodactyl mammal native to the northeast of the Democratic Republic of the Congo in Central Africa. Although the okapi bears striped markings reminiscent of zebras, it is most closely related to the giraffe. The okapi and the giraffe are the only living members of the family Giraffidae. The okapi stands about tall at the shoulder and has an average body length of about . Its weight ranges from . It has a long neck, and large, flexible ears. Its coat is a chocolate to reddish brown, much in contrast with the white horizontal stripes and rings on the legs and white ankles. Male okapis have short, hair-covered horns called ossicones, less than in length. Females possess hair whorls, and ossicones are absent. Okapis are primarily diurnal but may be active for a few hours in darkness. They are essentially solitary, coming together only to breed. Okapis are herbivores, feeding on tree leaves and buds, grasses, ferns, fruits, and fungi. Rut in males and estrus in females does not depend on the season. In captivity, estrous cycles recur every 15 days. The gestational period is around 440 to 450 days long, following which usually a single calf is born. The juveniles are kept in hiding, and nursing takes place infrequently. Juveniles start taking solid food from three months, and weaning takes place at six months. Okapis inhabit canopy forests at altitudes of . They are endemic to the tropical forests of the Democratic Republic of the Congo, where they occur across the central, northern and eastern regions. The International Union for the Conservation of Nature and Natural Resources (IUCN) classifies the okapi as Endangered. Major threats include habitat loss due to logging and human settlement. Extensive hunting for bushmeat and skin and illegal mining have also led to a decline in populations. The Okapi Conservation Project was established in 1987 to protect okapi populations. ==Etymology and taxonomy== The scientific name of the okapi is ''Okapia johnstoni''. It was first described by British zoologist Ray Lankester in 1901. The generic name ''Okapia'' derives from the Lese Karo name ''o'api'', while the specific name (''johnstoni'') is in recognition of the British Governor of Uganda, Sir Harry Johnston, who first acquired an okapi specimen for science from the Ituri Forest while repatriating a group of Pygmies to the Belgian Congo.〔Nowak, Ronald M (1999) ''Walker's Mammals of the World.'' 6th ed. p. 1085.〕 The animal was brought to prominent European attention by speculation on its existence found in press reports covering Henry Morton Stanley's journeys in 1887. Remains of a carcass were later sent to London by the English adventurer and colonial administrator Harry Johnston and became a media event in 1901. In 1901, zoologist Philip Sclater presented a painting of the okapi before the Zoological Society of London that depicted its physical features with some clarity. There was much confusion regarding the taxonomical status of this newly discovered animal. Sir Harry Johnston himself called it a ''Helladotherium'', or a relative of other extinct giraffids. Based on the description of the okapi by Pygmies, who referred to it as a "horse", Sclater named the species ''Equus johnstoni''. Subsequently, Lankester declared that the okapi represented an unknown genus of Giraffidae, which he placed in its own genus ''Okapia'', and assigned the name ''Okapia johnstoni'' to the species. In 1902, Swiss zoologist Charles Immanuel Forsyth Major suggested the inclusion of ''O. johnstoni'' in the extinct giraffid subfamily Palaeotraginae. However, the species was placed in its own subfamily Okapiinae, by Swedish palaeontologist Birger Bohlin in 1926, mainly due to the lack of a cingulum, a major feature of the palaeotragids. In 1986, ''Okapia'' was finally established as a sister genus of ''Giraffa'' on the basis of cladistic analysis. The two genera together with ''Palaeotragus'' constitute the tribe Giraffini. 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「Okapi」の詳細全文を読む スポンサード リンク
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