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The tawny eagle (''Aquila rapax'') is a large bird of prey. Like all eagles, it belongs to the family Accipitridae. It was once considered to be closely related to the migratory steppe eagle, ''Aquila nipalensis'', and the two forms have previously been treated as conspecific. They were split based on pronounced differences in morphology and anatomy;〔Clark, W. S. (1992): The taxonomy of Steppe and Tawny Eagles, with criteria for separation of museum specimens and live eagles. Bull. B.O.C. 112: 150–157〕〔Olson, Storrs L. (1994): Cranial osteology of Tawny and Steppe Eagles ''Aquila rapax'' and ''A. nipalensis''. Bull. B.O.C. 114: 264–267〕〔Sangster, George; Knox, Alan G.; Helbig, Andreas J. & Parkin, David T. (2002): Taxonomic recommendations for European birds. Ibis 144(1): 153–159 (PDF fulltext )〕 two molecular studies, each based on a very small number of genes, indicate that the species are distinct but disagree over how closely related they are.〔http://www.globalraptors.org/grin/SpeciesResults.asp?specID=8167〕 It breeds in most of Africa both north and south of the Sahara Desert and across tropical southwestern Asia to India. It is a resident breeder which lays 1–3 eggs in a stick nest in a tree, crag or on the ground. Throughout its range it favours open dry habitats, such as desert, semi-desert, steppes, or savannah, plains. ==Description== This is a large eagle although it is one of the smaller species in the ''Aquila'' genus. It is in length and has a wingspan of . Weight can range from .〔''Raptors of the World'' by Ferguson-Lees, Christie, Franklin, Mead & Burton. Houghton Mifflin (2001), ISBN 0-618-12762-3.〕〔() (2011).〕 It has tawny upperparts and blackish flight feathers and tail. The lower back is very pale. This species is smaller and paler than the Steppe eagle, although it does not share that species' pale throat. Immature birds are less contrasted than adults, but both show a range of variation in plumage colour. 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「Tawny eagle」の詳細全文を読む スポンサード リンク
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