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The Alpine chough , or yellow-billed chough, (''Pyrrhocorax graculus'') is a bird in the crow family, one of only two species in the genus ''Pyrrhocorax''. Its two subspecies breed in high mountains from Spain east through southern Europe and North Africa to Central Asia, India and China, and it may nest at a higher altitude than any other bird. The eggs have adaptations to the thin atmosphere that improve oxygen take-up and reduce water loss. This bird has glossy black plumage, a yellow bill, red legs, and distinctive calls. It has a buoyant acrobatic flight with widely spread flight feathers. The Alpine chough pairs for life and displays fidelity to its breeding site, which is usually a cave or crevice in a cliff face. It builds a lined stick nest and lays three to five brown-blotched whitish eggs. It feeds, usually in flocks, on short grazed grassland, taking mainly invertebrate prey in summer and fruit in winter; it will readily approach tourist sites to find supplementary food. Although it is subject to predation and parasitism, and changes in agricultural practices have caused local population declines, this widespread and abundant species is not threatened globally. Climate change may present a long-term threat, by shifting the necessary alpine habitat to higher altitudes. ==Taxonomy== The Alpine chough was first described as ''Corvus graculus'' by Linnaeus in the ''Systema Naturae'' in 1766. It was moved to its current genus, ''Pyrrhocorax'', by English ornithologist Marmaduke Tunstall in his 1771 ''Ornithologia Britannica'', along with the only other member of the genus, the red-billed chough, '' P. pyrrhocorax''. The closest relatives of the choughs were formerly thought to be the typical crows, ''Corvus'', especially the jackdaws in the subgenus ''Coloeus'', but DNA and cytochrome b analysis shows that the genus ''Pyrrhocorax'', along with the ratchet-tailed treepie (genus ''Temnurus''), diverged early from the rest of the Corvidae. The genus name is derived from Greek ''πύρρος (purrhos)'', "flame-coloured", and ''κόραξ (korax)'', "raven". The species epithet ''graculus'' is Latin for a jackdaw. The current binomial name of the Alpine chough was formerly sometimes applied to the red-billed chough. The English word "chough" was originally an alternative onomatopoeic name for the jackdaw, ''Corvus monedula'', based on its call. The red-billed chough, formerly particularly common in Cornwall and known initially as the "Cornish chough", eventually became just "chough", the name transferring from one genus to another. The Alpine chough has two extant subspecies. * ''P. g. graculus'', the nominate subspecies in Europe, north Africa, Turkey, the Caucasus and northern Iran.〔 * ''P. g. digitatus'', described by the German naturalists Wilhelm Hemprich and Christian Gottfried Ehrenberg as ''P. alpinus'' var. ''digitatus'' in 1833, is larger and has stronger feet than the nominate race.〔 It breeds in the rest of the depicted Asian range, mainly in the Himalayas.〔 Moravian palaeontologist Ferdinand Stoliczka separated the Himalayan population as a third subspecies, ''P. g. forsythi'', but this has not been widely accepted and is usually treated as synonymous with ''digitatus''. A Pleistocene form from Europe was similar to the extant subspecies, and is sometimes categorised as ''P. g. vetus''.〔(Hungarian with English abstract) Válóczi, Tibor (1999) "(Vaskapu-barlang (Bükk-hegység) felső pleisztocén faunájának vizsgálata (Investigation of the Upper-Pleistocene fauna of Vaskapu-Cave (Bükk-mountain)) ). ''Folia historico naturalia musei Matraensis'' 23: 79–96 (PDF)〕〔Mlíkovský, Jirí (2002) (''Cenozoic birds of the world'' ) (Part 1: Europe). Ninox Press, Prague. p. 238〕 The Australian white-winged chough, ''Corcorax melanorhamphos'', despite its similar bill shape and black plumage, is only distantly related to the true choughs.〔(【引用サイトリンク】url= http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=557570 )〕 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「Alpine chough」の詳細全文を読む スポンサード リンク
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