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''Sturnus'' is a genus of starlings. As discussed below, the taxonomy of this group is complex, and other authorities differ considerably in which species they place in this genus, and in the species boundaries within ''Sturnus''. This genus has representatives across most of Eurasia and one species, the European starling, has been introduced to South Africa, North America, Australia and New Zealand. The ''Sturnus'' starlings are terrestrial species; they walk rather than hop, and have modifications to the skull and its muscles for open-bill probing. The latter adaptation has facilitated the spread of this genus from humid tropical southern Asia to cooler regions of Europe and Asia. The more northerly breeding species are completely or partially migratory, wintering in warmer regions. ''Sturnus'' starlings nest in holes in trees or buildings. They are omnivorous and mostly feed on the ground; they specialise in taking invertebrates from just below the surface. This is facilitated by the head adaptations mentioned above, which enable the birds to probe with the bill open, closing it to secure prey items. The plumages within this group are variable, but all the species have the starling's familiar triangular wing shape. ==Systematics== The European (the type species) and spotless starlings are particularly closely related, and interbreed to some extent where their ranges overlap in southwestern France and northeastern Spain. The non-migratory spotless starling may be descended from a population of ancestral ''S. vulgaris'' that survived in an Iberian refugium during an ice age retreat. The other species have been placed in this, closely related, or their own genera in the past. As delimited here, the genus ''Sturnus'' is an evolutionary grade and not a monophyletic group (Zuccon ''et al.'' 2006). It appears as if ''Acridotheres'', ''Leucopsar'', ''Sturnia'', and possibly others would have to be included here to make the present genus a truly evolutionary group (Jønsson & Fjeldså 2006). However, this would create an even more diverse and less informative assemblage, so it is probably more advisable to split the genus into several, reinstating taxa such as ''Pastor'' and ''Temenuchus'' and redelimiting some of the disputed genera above while merging others. This has to wait for a more thorough study of all species' relationships; in the meantime, the old taxonomic sequence is preserved and suspected affiliations of the currently included species are remarked upon: *Red-billed starling, ''Sturnus sericeus'' - close to white-cheeked starling and thus probably belongs into ''Acridotheres'' or distinct genus〔See Jønsson & Fjeldså (2006).〕 *White-cheeked starling, ''Sturnus cineraceus'' - appears to be related to ''Acridotheres'', but maybe a distinct genus located between ''Acridotheres'' and ''Sturnia''〔〔See Zuccon ''et al.'' (2006).〕 *Common starling, ''Sturnus vulgaris'' - retained in this genus〔〔 *Spotless starling, ''Sturnus unicolor'' - retained in this genus〔〔 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「Sturnus」の詳細全文を読む スポンサード リンク
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