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The southern pied babbler (''Turdoides bicolor'') is a species of bird in the Leiothrichidae family, found in dry savannah of Botswana, Namibia, South Africa, and Zimbabwe. ==Description== The southern pied babbler is a medium-sized cooperatively breeding passerine bird. Groups range in size from 2-16 adults, but pairs are rare. The species is sexually monomorphic, with males and females indistinguishable from physical characteristics. Each group comprises a dominant breeding pair that monopolise access to breeding opportunities.〔Nelson-Flower, Martha J.; Hockey, Phil A.R.; O‘Ryan, Colleen; Raihani, Nichola J.; du Plessisa, Morné A. and Ridley, Amanda R.; (“Monogamous dominant pairs monopolize reproduction in the cooperatively breeding pied babbler” ); in ''Behavioral Ecology'' (2011) doi: 10.1093/beheco/arr018〕 Recent genetic research has confirmed that these dominant pairs are responsible for more than 95% of young hatched.〔 Occasional mixed parentage has been observed, but is predictable in most cases: subordinates primarily gain parentage when a new (unrelated) immigrant disperses into the group, or a new group is founded.〔 All group members cooperate to help raise the young hatched from a single clutch. Clutch size varies between two and five, with a modal clutch size of three. Cooperative behaviours include: provisioning young (both in the nest and post-fledging), sentinel behaviour, territory border defense, teaching behaviour and babysitting behaviour (where semi-independent fledglings follow adults between foraging sites and away from predators). The breeding season extends from late-September to early April, although this varies between years and is strongly rain-dependent. Groups can raise up to three successful clutches per breeding season. Average incubation time is 14 days, and average time between hatching and fledging is 16 days. Fledging time varies according to group size: small groups tend to fledge their young earlier than large groups.〔Raihani, N.J. & Ridley, A.R.; “Variable fledging age according to group size: tradeoffs in a cooperative bird”, in ''Biology Letters'' 3 (2007), pp. 624-627. 〕 Post-fledging, young are poorly mobile, unable to fly, and rely entirely on adult group members for food. Fledgling foraging efficiency develops slowly, and fledglings can continue to be provisioned by adults for up to four months post-fledging. The amount of care that young receive during this stage has long-term effects: fledglings that receive care for the longest periods tend to be heavier and better foragers than their counterparts. In addition, they are more likely to successfully disperse from their natal group and consequently begin reproducing earlier than their “failed-disperser” counterparts.〔Ridley, Amanda R. b and Raihani, Nichola J.; “Variable postfledging care in a cooperative bird: causes and consequences”; in ''Behavioral Ecology'', volume 18, issue 6, pp. 994-1000.〕 thumb thumb 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「Southern pied babbler」の詳細全文を読む スポンサード リンク
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