Effects of predation risk on foraging behaviour and group size: adaptations in a social cooperative species
Effects of predation risk on foraging behaviour and group size: adaptations in a social cooperative species
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捕食风险对觅食行为和群体规模的影响：社会合作物种的适应
DOI：
10.1016/j.anbehav.2012.07.003
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发表时间：
2012
期刊：
影响因子：
2.5
通讯作者：
A. Russell
中科院分区：
文献类型：
--
作者：
E. Sorato;Philippa R. Gullett;S. Griffith;A. Russell
有一个分歧的模型之间的进化研究组生活在物种中的群体主要是基于家庭和那些基于流体聚集的非亲属。在前者中，责任一直在选择后代philopatry的生态和人口因素;在后者中，更典型地强调觅食成功和捕食风险等因素的重要性。我们研究了捕食风险和群体大小和觅食行为之间的关联，在栗冠穗鹛，Pomatostomus ruficeps，一个家庭生活的合作繁殖的鸟，似乎没有面临经典的生态或人口的限制扩散和繁殖。群体更容易遇到，并被攻击，鸟类捕食者依赖年轻时存在。大型群体也更有可能遇到捕食者，但不太可能受到它的攻击，这与早期捕食者检测或混淆效应的群体生活的好处相一致。此外，由于稀释效应，与小群体相比，大群体中特定个体被捕食的平均风险降低。捕食可能会部分选择在这个物种的群体生活的研究结果表明，减少地面觅食和增加哨兵行为时，捕食风险较高。我们的结论是，捕食可能是一个重要的力量选择的社会性，在栗冠穗鹛，并强调需要在未来的研究中考虑更明确的内在利益，以群体生活在进化的脊椎动物合作繁殖系统。
There is a divergence between models examining the evolution of group living in species in which groups are largely based on families and those based on fluid aggregations of nonrelatives. In the former, the onus has been on ecological and demographic factors that select for offspring philopatry; in the latter, the importance of factors such as foraging success and predation risk are more typically emphasized. We examined the association between predation risk and both group size and foraging behaviour in the chestnut-crowned babbler, Pomatostomus ruficeps, a family-living cooperatively breeding bird that does not appear to face classic ecological or demographic constraints on dispersal and breeding. Groups were more likely to encounter, and be attacked by, avian predators when dependent young were present. Large groups were also more likely to encounter a predator, but less likely to be attacked by it, consistent with a benefit of group living through early predator detection or confusion effects. In addition, the average risk of predation for a given individual was reduced in large groups compared to small ones, owing to the dilution effect. That predation might partly select for group living in this species is boosted by findings showing reductions in ground foraging and increases in sentinel behaviour when predation risk was higher. We conclude that predation might represent an important force selecting for sociality in chestnut-crowned babblers, and highlight the need for future studies to consider more explicitly inherent benefits to group living in the evolution of vertebrate cooperative breeding systems.