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MacQueen's bustard (''Chlamydotis macqueenii'') is a large bird in the bustard family. It was earlier included as a subspecies of the houbara bustard (''Chlamydotis undulata'') and sometimes known as the Asian houbara. The subspecies are geographically separated from the houbara found west of the Sinai Peninsula in North Africa with a population in the Canary Islands. MacQueen's bustard is found in the desert and steppe regions of Asia, east from the Sinai Peninsula extending across Kazhakstan east to Mongolia. These two species are the only members of the genus ''Chlamydotis''. MacQueen's is a partial latitudinal migrant while the houbara bustard is more sedentary. In the 19th century, vagrants were found as far west of their range as Great Britain. Populations have decreased by 20 to 50% from 1984 to 2004 due mainly to hunting and land-use changes. ==Description== This medium-sized bustard is about long with a wingspan. It is brown above and white below, with black stripes down the sides of the neck. In flight, the long wings show large areas of black and brown on the flight feathers and a white patch at the base of the primaries. From below the wing is mostly white with a black trailing edge. Sexes are similar, but the female is smaller and paler above.〔 MacQueen's bustard is very silent except for the sounds that males make in their display. Like other bustards, they have a flamboyant display, raising the white feathers of the head and throat and withdrawing the head while walking around a chosen lek site. Males and females are nearly identical in plumage but males are slightly larger than females. A study of the morphometrics of MacQueen's bustards from Pakistan based on about 79 individuals of known sex showed that the males were 9 to 15% larger than females on most measurements. The use of discriminant analysis allowed correct identification of the sexes based on morphometrics in about 99% of the cases.〔 MacQueen's bustard was once included as one of three subspecies of the houbara. The lack of intermediate forms on the edges where their distributions meet (presumed to be in the Nile valley), differences in morphology and display behaviour led to their being elevated to full species. The houbara bustard now refers only to the North African population (included as the nominate subspecies ''C. undulata undulata'') and a small population on the Canary Islands (''C. u. fuertaventurae''). MacQueen's is larger than the houbara and much paler. The feathers on the top of the head include some long and curved feathers which are white or black with white bases. In the houbara, these crest feathers are all white and the difference is evident during the display of the male.〔 Estimates based on the divergence of mitochondrial DNA sequence suggest that the species separated from the common ancestors of ''C. u. undulata'' and ''C. u. fuertaventurae'' nearly 430,000 years ago.〔 This divergence may have begun 900,000 years ago, at a time of extreme aridity.〔 The wide dispersal abilities of MacQueen's bustard ensure that their genes are more well mixed unlike the geographically structured genetic patterns shown by the African houbara.〔 The species name is after the collector Thomas MacQueen, from whose collection〔 it was named by John Edward Gray in his illustrated catalogue of Indian Zoology based on the collections (some being illustrations made by Indian artists) of Major-General Thomas Hardwicke. It has been suggested that this was a Major Thomas MacQueen.〔 It was originally placed in the genus ''Otis''.〔 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「MacQueen's bustard」の詳細全文を読む スポンサード リンク
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