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An extinct in the wild (EW) species is one which has been categorized by the International Union for Conservation of Nature as only known by living members kept in captivity or as a naturalized population outside its historic range due to massive habitat loss.〔IUCN, (2001 IUCN Red List Categories and Criteria: Version 3.1 ) p.14 Last visited: 30 May 2010.〕 ==Examples== Examples of species and subspecies that are extinct in the wild include: *Alagoas curassow (extinct in the wild since 1988) *Black soft-shell turtle (extinct in the wild since 2002) *Escarpment cycad (extinct in the wild since 2006) *Guam rail (extinct in the wild since the 1980s) *Hawaiian crow (extinct in the wild since 2002) *Père David's deer (extinct in the wild since 1865 and possibly long before that) *Scimitar oryx (extinct in the wild since 1998) *Socorro dove (extinct in the wild since 1972) *Wyoming toad (extinct in the wild since 1991) *Possibly the axolotl (studies in 2014 failed to find wild individuals in their known range)〔(【引用サイトリンク】title=The Axolotl, Mexico's 'Water Monster,' May Have Disappeared From Its Only Natural Habitat )〕 The Pinta Island tortoise (''Geochelone nigra abingdoni'') had only one living individual, named Lonesome George, until his death in June 2012. The tortoise was believed to be entirely extinct in the mid-20th century, until Hungarian malacologist József Vágvölgyi spotted Lonesome George on the Galapagos island of Pinta on 1 December 1971. Since then, Lonesome George has been a powerful symbol for conservation efforts in general and for the Galapagos Islands in particular. With his death on 24 June 2012, the subspecies is again believed to be extinct. With the discovery of 17 hybrid Pinta tortoises located at nearby Wolf Volcano a plan has been made to attempt to breed the subspecies back into a pure state. If successful, this would be the first time a species has been recovered from having been declared extinct. Not all species that are extinct in the wild are rare. For example, ''Ameca splendens'', though extinct in the wild, was a popular fish among aquarists for some time, but hobbyist stocks have declined quite a lot more recently, placing its survival in jeopardy.〔 (2006): Captive breeding promotes aggression in an endangered Mexican fish. ''Biological Conservation'' 133(2): 169–177. (HTML abstract)〕 However, the ultimate purpose of preserving biodiversity is to maintain ecological function. When a species exists only in captivity, it is ecologically extinct. 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「Extinct in the wild」の詳細全文を読む スポンサード リンク
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