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The rufous-crowned sparrow (''Aimophila ruficeps'') is a smallish American sparrow. This passerine is primarily found across the Southwestern United States and much of the interior of Mexico, south to the transverse mountain range, and to the Pacific coast to the southwest of the transverse range. Its distribution is patchy, with populations often being isolated from each other. Twelve subspecies are generally recognized, though up to eighteen have been suggested. This bird has a brown back with darker streaks and gray underparts. The crown is rufous, and the face and supercilium are gray with a brown or rufous streak extending from each eye and a thick black malar streak. These sparrows feed primarily on seeds in the winter and insects in the spring and summer. The birds are often territorial, with males guarding their territory through song and displays. Flight is awkward for this species, which prefers to hop along the ground for locomotion. They are monogamous and breed during spring. Two to five eggs are laid in the bird's nest, which is cup-shaped and well hidden. Adult sparrows are preyed upon by house cats and small raptors, while young may be taken by a range of mammals and reptiles. They have been known to live for up to three years, two months. Although the species has been classified as least concern, or unthreatened with extinction, some subspecies are threatened by habitat destruction and one may be extinct. ==Taxonomy== This bird belongs to the family Emberizidae, which consists of the American sparrows and Eurasian buntings. The American sparrows are seed-eating New World birds with conical bills, brown or gray plumage, and distinctive head patterns. Birds in the genus ''Aimophila'' tend to be medium-sized at in length, live in arid scrubland, have long bills and tails in proportion to their body size as well as short, rounded wings, and build cup-shaped nests.〔〔 The rufous-crowned sparrow was described in 1852 by American ornithologist John Cassin as ''Ammodramus ruficeps''.〔 It has also been described as belonging to the genus ''Peucaea'', which contains several sparrows in the genus ''Aimophila'' that share characteristics, such as a larger bill and a patch of yellow under the bend of the wing, that other members of the genus do not.〔〔 However, splitting the ''Peucaea'' sparrows into a separate genus is not generally recognized.〔〔 A 2008 phylogenetic analysis of the genus ''Aimophila'' divided it into four genera, with the rufous-crowned sparrow and its two closest relatives, the Oaxaca sparrow and rusty sparrow, being maintained as the genus ''Aimophila''.〔 In addition, this study suggested that the rufous-crowned sparrow may be more closely related to the brown towhees of the genus ''Pipilo'' than the other members of the historical genus ''Aimophila''.〔 The derivation of the current genus name, ''Aimophila'', is from the Greek ''aimos''/ἀιμος, meaning "thicket", and ''-philos''/-φιλος, meaning "loving".〔 The specific epithet is a literal derivation of the common name, derived from the Latin ''rufus'', meaning "reddish" or "tawny", and ''-ceps'', from ''caput'', meaning "head".〔 The bird is also occasionally referred to colloquially as the rock sparrow because of its preference for rocky slopes.〔 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「Rufous-crowned sparrow」の詳細全文を読む スポンサード リンク
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