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The turkey vulture (''Cathartes aura''), also known in some North American regions as the turkey buzzard (or just buzzard), and in some areas of the Caribbean as the John crow or carrion crow,〔(Turkey Vulture (''Cathartes aura'') ). peregrinefund.org〕 is a vulture that is the most widespread of the New World vultures.〔(【引用サイトリンク】 work =Britannica Concise Encyclopedia )〕 One of three species in the genus ''Cathartes'' of the family Cathartidae, the turkey vulture ranges from southern Canada to the southernmost tip of South America. It inhabits a variety of open and semi-open areas, including subtropical forests, shrublands, pastures, and deserts.〔 Like all New World vultures, it is not closely related to the Old World vultures of Europe, Africa, and Asia. The two groups strongly resemble each other because of convergent evolution; natural selection often leads to similar body plans in animals that adapt independently to the same conditions. The turkey vulture is a scavenger and feeds almost exclusively on carrion.〔 It finds its food using its keen eyes and sense of smell, flying low enough to detect the gases produced by the beginnings of the process of decay in dead animals.〔 In flight, it uses thermals to move through the air, flapping its wings infrequently. It roosts in large community groups. Lacking a syrinx—the vocal organ of birds—its only vocalizations are grunts or low hisses. It nests in caves, hollow trees, or thickets. Each year it generally raises two chicks, which it feeds by regurgitation.〔 It has very few natural predators.〔 In the United States, the vulture receives legal protection under the Migratory Bird Treaty Act of 1918.〔 == Taxonomy == The turkey vulture received its common name from the resemblance of the adult's bald red head and its dark plumage to that of the male wild turkey, while the name "vulture" is derived from the Latin word ''vulturus'', meaning "tearer," and is a reference to its feeding habits. The word ''buzzard'' is used by North Americans to refer to this bird, yet in the Old World that term refers to members of the genus ''Buteo''. The generic term ''Cathartes'' means "purifier" and is the Latinized form from the Greek ''kathartēs''/καθαρτης. The turkey vulture was first formally described by Linnaeus as ''Vultur aura'' in his ''Systema Naturae'' in 1758, and characterised as ''V. fuscogriseus, remigibus nigris, rostro albo'' ("brown-gray vulture, with black wings and a white beak"). It is a member of the family Cathartidae, along with the other six species of New World vultures, and included in the genus ''Cathartes'', along with the greater yellow-headed vulture and the lesser yellow-headed vulture. Like other New World vultures, the turkey vulture has a diploid chromosome number of 80. The taxonomic placement of the turkey vulture and the remaining six species of New World vultures has been in flux.〔Remsen, J. V., Jr.; C. D. Cadena; A. Jaramillo; M. Nores; J. F. Pacheco; M. B. Robbins; T. S. Schulenberg; F. G. Stiles; D. F. Stotz & K. J. Zimmer. (2007). ( ''A classification of the bird species of South America.'' ) South American Classification Committee. Retrieved 2007–10–15〕 Though both are similar in appearance and have similar ecological roles, the New World and Old World vultures evolved from different ancestors in different parts of the world. Some earlier authorities suggested that the New World vultures were more closely related to storks.〔Sibley, Charles G. and Burt L. Monroe. (1990). ''(Distribution and Taxonomy of the Birds of the World )''. Yale University Press. ISBN 0-300-04969-2. Retrieved 2007-04-11.〕 More recent authorities maintained their overall position in the order Falconiformes along with the Old World vultures〔Sibley, Charles G., and Jon E. Ahlquist. (1991). ''(Phylogeny and Classification of Birds: A Study in Molecular Evolution )''. Yale University Press. ISBN 0-300-04085-7. Retrieved 2007-04-11.〕 or place them in their own order, Cathartiformes. However, recent genetic studies have made it clear that neither New World or Old World vultures are close to falcons, nor are New World vultures close to storks. Both are basal members of the clade Afroaves,〔 with Old World vultures comprising several groups within the family Accipitridae, also containing eagles, kites, and hawks,〔 while New World vultures in Cathartiformes are a sister group to Accipitriformes (containing the osprey and secretarybird along with Accipitridae). There are five subspecies of turkey vulture: * ''C. a. aura'' is the nominate subspecies. It is found from Mexico south through South America and the Greater Antilles. This subspecies occasionally overlaps its range with other subspecies. It is the smallest of the subspecies but is nearly indistinguishable from ''C. a. meridionalis'' in color.〔 * ''C. a. jota'', the Chilean turkey vulture, is larger, browner, and slightly paler than ''C. a. ruficollis''. The secondary feathers and wing coverts may have gray margins. * ''C. a. meridionalis'', the western turkey vulture, is a synonym for ''C. a. teter''. ''C. a. teter'' was identified as a subspecies by Friedman in 1933, but in 1964 Alexander Wetmore separated the western birds, which took the name ''meridionalis'', which was applied earlier to a migrant from South America. It breeds from southern Manitoba, southern British Columbia, central Alberta and Saskatchewan south to Baja California, south-central Arizona, southeast New Mexico, and south-central Texas. It is the most migratory subspecies, migrating as far as South America, where it overlaps the range of the smaller ''C. a. aura''. It differs from the eastern turkey vulture in color, as the edges of the lesser wing coverts are darker brown and narrower.〔 * ''C. a. ruficollis'' is found in Panama south through Uruguay and Argentina. It is also found on the island of Trinidad.〔 It is darker and more black than ''C. a. aura'', with brown wing edgings which are narrower or absent altogether. The head and neck are dull red with yellow-white or green-white markings. Adults generally have a pale yellow patch on the crown of the head.〔 * ''C. a. septentrionalis'' is known as the eastern turkey vulture. The eastern and western turkey vultures differ in tail and wing proportions. It ranges from southeastern Canada south through the eastern United States. It is less migratory than ''C. a. meridionalis'' and rarely migrates to areas south of the United States. 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「Turkey vulture」の詳細全文を読む スポンサード リンク
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