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Le Conte's thrasher (''Toxostoma lecontei'') is a pale bird found in the southwestern United States and northwestern Mexico. It prefers to live in deserts with very little vegetation, where it blends in with the sandy soils. Le Conte's thrashers are nonmigratory birds that reside in the same territory annually. Although the species has been decreasing in certain areas of its range, in particular California, it still is abundant enough to not be considered for vulnerable status. These birds are terrestrial and only fly occasionally. Both sexes are heavily involved in the nest building, incubating, and brooding process, though each alternates with primary responsibility of the tasks. Le Conte's thrashers frequently compete with species such as the northern mockingbird, loggerhead shrike and greater roadrunner, as well as being potential prey for the latter. ==Taxonomy== Le Conte's thrasher is named after Dr. John Lawrence LeConte, an entomologist who eventually became president of the American Association for the Advancement of Science. There are two subspecies: ''T.l. lecontei'' (Lawrence, 1851) – range is from southwestern United States (south central and eastern California, southwest Utah, and south central Arizona) to northwestern Mexico (north east Baja California and northwest Sonora).〔 ''T.l. arenicola'' (Anthony, 1897) Rosalia thrasher; west coast of Baja California.〔〔 ''T.l. arenicola'' has been proposed by the American Ornithologists Union as separate species,〔 and treated as a separate species by other authors.〔 and a name of Vizcaino thrasher if it becomes official.〔 T.l. arenicola still is treated as a subspecies of ''lecontei'' by some authors, however.〔 A proposed race ''T.c. macmillanorum'' only exhibits minor differences in plumage from ''T.l. lecontei'' (such as a darker crown and lighter flanks), but is not justified by biochemical or morphological grounds.〔 One study suggested that the phylogeographic structure of the Le Conte's is consistent with both its geographic distribution and genetics, with the Vizcaíno Desert in Baja California acting as a barrier initiating allopatric speciation. The two closest living relatives of Le Conte's thrasher, the California thrasher and the crissal thrasher, form as the ''lecontei'' group. The similarities with these three species contrasted with other ''Toxostoma'' thrashers, in particular the sickle-shaped bill, longer legs and smaller wings indicated its adaption to a preference to running and digging for food. 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「Le Conte's thrasher」の詳細全文を読む スポンサード リンク
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