Ashton Benjamin J, Thornton Alex, Ridley Amanda R
Centre for Evolutionary Biology, University of Western Australia, Perth, Australia.
School of Biological Sciences, University of Bristol, Bristol, UK.
Anim Behav. 2019 Dec;158:1-7. doi: 10.1016/j.anbehav.2019.10.004.
The benefits of group living have traditionally been attributed to risk dilution or the efficient exploitation of resources; individuals in social groups may therefore benefit from access to valuable information. If sociality facilitates access to information, then individuals in larger groups may be predicted to solve novel problems faster than individuals in smaller groups. Additionally, larger group sizes may facilitate the subsequent spread of innovations within animal groups, as has been proposed for human societies. We presented a novel foraging task (where a food reward could be accessed by pushing a self-shutting sliding door) to 16 groups of wild, cooperatively breeding Australian magpies, , ranging in size from two to 11 individuals. We found a nonlinear decline in the time taken for the innovative behaviour to emerge with increasing group size, and social information use facilitated the transmission of novel behaviour, with it spreading more quickly in larger than smaller groups. This study provides important evidence for a nonlinear relationship between group size and the emergence of innovation (and its subsequent transmission) in a wild population of animals. Further work investigating the scope and strength of group size-innovation relationships, and the mechanisms underpinning them, will help us understand the potential advantages of living in larger social groups.
群居的好处传统上被归因于风险稀释或资源的有效利用；因此，社会群体中的个体可能会从获取有价值的信息中受益。如果社交性有助于获取信息，那么可以预测，大群体中的个体比小群体中的个体能更快地解决新问题。此外，更大的群体规模可能会促进创新在动物群体中的后续传播，正如人类社会所提出的那样。我们向16组野生的、合作繁殖的澳大利亚喜鹊展示了一项新颖的觅食任务（通过推开一扇自动关闭的滑动门可以获得食物奖励），每组喜鹊数量从2只到11只不等。我们发现，随着群体规模的增加，创新行为出现所需的时间呈非线性下降，并且社会信息的使用促进了新行为的传播，在大群体中比小群体中传播得更快。这项研究为动物野生种群中群体规模与创新出现（及其后续传播）之间的非线性关系提供了重要证据。进一步研究群体规模与创新关系的范围和强度及其背后的机制，将有助于我们理解生活在更大社会群体中的潜在优势。
