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The woodcreepers (Dendrocolaptinae) comprise a subfamily of sub-oscine passerine birds endemic to the Neotropics. They have traditionally been considered a distinct family Dendrocolaptidae, but most authorities now place them as a subfamily of the ovenbirds (Furnariidae). They superficially resemble the Old World treecreepers, but they are unrelated and the similarities are due to convergent evolution. The subfamily contains around 57 species in 15 to 20 genera. Woodcreepers range from 14 to 35 centimetres in length. Generally brownish birds, the true woodcreepers maintain an upright vertical posture, supported by their stiff tail vanes. They feed mainly on insects taken from tree trunks. However, woodcreepers often form part of the core group at the centre of flocks attending army ant swarms. Woodcreepers are arboreal cavity-nesting birds; two or three white eggs are laid and incubated for about 15 to 21 days.〔 These birds can be difficult to identify in that they tend to have similar brown upperparts, and the more distinctive underparts are hard to see on a bird pressed against a trunk in deep forest shade. The bill shape, extend/shape of spots/streaks, and call are useful aids to determining species. ==Description== The woodcreepers are generally fairly uniform in appearance. They range in size from 13 cm (the wedge-billed woodcreeper) to 35 cm in length (the strong-billed woodcreeper). Males tend to be slightly larger than females on average, but there is considerable overlap in size in most species. Pronounced sexual dimorphism in size and plumage is rare. Bill size and shape accounts for much of the variation between the species. Bills can be straight or highly decurved, and can account for as much as a quarter of the length of the bird (as happens in the long-billed woodcreeper). The plumage is usually subdued and often brown, or sometimes rufous or other dark colours. Many species have patterns such as checking, spotting or barring on their plumage. The feathers of the tail are rigid and are used for supporting the body when climbing tree trunks; the tail can support most of the body weight and birds that lose their tail find climbing difficult. Woodcreepers climb by flexing their legs and hopping up the trunk. The feet of the woodcreepers are also modified for climbing. The front three toes are strongly clawed and the back tow is strong and long. The legs are also strong.〔Remsen, J. Van (2003): Family Dendrocolaptidae (Woodcreepers). ''In:'' del Hoyo, Josep; Elliott, Andrew & Sargatal, Jordi (editors): ''Handbook of Birds of the World, Volume 6: Broadbills to Tapaculos'': 358–447. Lynx Edicions, Barcelona. ISBN 84-87334-50-4〕 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「woodcreeper」の詳細全文を読む スポンサード リンク
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