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The gaur (, ''Bos gaurus''), also called Indian bison, is the largest extant bovine, native to South Asia and Southeast Asia. The species is listed as vulnerable on the IUCN Red List since 1986, as the population decline in parts of the species' range is likely to be well over 70% during the last three generations. Population trends are stable in well-protected areas, and are rebuilding in a few areas which had been neglected. The gaur is the tallest species of wild cattle.〔Lydekker, R. (1888–1890). (''The new natural history'' Volume 2 ). Printed by order of the Trustees of the British Museum (Natural History), London.〕 The Malayan gaur is called ''seladang'', and the Burmese gaur is called ''pyoung'' .〔Hubback, T. R. (1937). ''The Malayan gaur or seladang''. Journal of Mammalogy 18 (3): 267–279.〕 The domesticated form of the gaur ''Bos frontalis'' is called ''gayal'' or ''mithun''.〔Nowak, R. M. (1999). (''Gaur'' ) Pages 1158–1159 in ''Walker's Mammals of the World. Volume 1.'' The Johns Hopkins University Press, Baltimore, USA and London, UK.〕 ==Characteristics== The gaur is a strong and massively built species with a high convex ridge on the forehead between the horns, which bends forward, causing a deep hollow in the profile of the upper part of the head. There is a prominent ridge on the back. The ears are very large; the tail only just reaches the hocks, and in old bulls the hair becomes very thin on the back. In colour, the adult male gaur is dark brown, approaching black in very old individuals; the upper part of the head, from above the eyes to the nape of the neck, is, however, ashy grey, or occasionally dirty white; the muzzle is pale coloured, and the lower part of the legs are pure white or tan. The cows and young bulls are paler, and in some instances have a rufous tinge, which is most marked in groups inhabiting dry and open districts. The tail is shorter than in the typical oxen, reaching only to the hocks. They have a distinct ridge running from the shoulders to the middle of the back; the shoulders may be as much as higher than the rump. This ridge is caused by the great length of the spinous processes of the vertebrae of the fore-part of the trunk as compared with those of the loins. The hair is short, fine and glossy, and the hooves are narrow and pointed.〔 The gaur has a head-and-body length of with a long tail, and is high at the shoulder. The average weight of adult gaur is , with an occasional large bull weighing up to .〔Smith, A. T., Xie, Y. (eds.) (2008). (''A Guide to the Mammals of China'' ). Princeton University Press, Princeton Oxforshire. Page 472.〕 Males are about one-fourth larger and heavier than females.〔 In general measurements are derived from gaurs surveyed in India and China. The Seladang, or Malayasian subspecies, may average larger but no scientifically published measurements are known.〔Hubback, T. R. (1937). ''The Malayan gaur or seladang''. Journal of Mammalogy: 267-279.〕〔Ogilvie, C. S. (1953). ''The behaviour of seladang (Bibos gaurus)''. Oryx 2 (03): 167-169.〕 Gaur do not have a distinct dewlap on the throat and chest. Both sexes carry horns, which grow from the sides of the head, curving upwards. Between the horns is a high convex ridge on the forehead. At their bases they present an elliptical cross-section, a characteristic that is more strongly marked in bulls than in cows. The horns are decidedly flattened at the base and regularly curved throughout their length, and are bent inward and slightly backward at their tips. The colour of the horns is some shade of pale green or yellow throughout the greater part of their length, but the tips are black.〔 The horns, of medium size by large bovid standards, grow to a length of .〔 The cow is considerably lighter in make and in colour than the bull. The horns are more slender and upright, with more inward curvature, and the frontal ridge is scarcely perceptible. In young animals the horns are smooth and polished. In old bulls they are rugged and dented at the base. Gaur are among the largest living land animals. Only elephants, rhinos, the hippopotamus (''Hippopotamus amphibius'') and the giraffe (''Giraffa camelopardalis'') consistently grow heavier. Two species that naturally co-exist with the gaur are heavier: the Asian elephant (''Elephas maximus'') and Indian rhinoceros (''Rhinoceros unicornis'').〔Schaller, G. B., Simon, N. M. (1969). ''The endangered large mammals of Asia''. In: Holloway, C. W. (ed.) IUCN Eleventh Technical Meeting. Papers and Proceedings, 25–28 November 1969, New Delhi, India. Volume II. IUCN Publications new series No. 18, Morges, Switzerland. Pp. 11-23.〕〔Hislop, J. A. (1966). ''Rhinoceros and seladang—Malaya's vanishing species''. Oryx 8 (06): 353-359.〕 By most standards of measurements, gaur is the largest wild bovid alive today. However, the shorter-legged, bulkier Wild water buffalo (''Bubalus arnee'') is similar in average body mass, if not maximum weight.〔〔Owen-Smith, R. N. (1992). ''Megaherbivores: the influence of very large body size on ecology''. Cambridge University Press.〕 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「Gaur」の詳細全文を読む スポンサード リンク
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