Core Facility Konrad Lorenz Forschungsstelle for Behaviour and Cognition, University of Vienna, Fischerau 11, 4645, Gruenau im Almtal, Austria.
Department of Behavioural Biology, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria.
Sci Rep. 2019 Sep 6;9(1):12839. doi: 10.1038/s41598-019-49293-9.
Living in groups has various advantages and disadvantages for group members. We investigated the fitness consequences of early social connectivity (normalized Freeman degrees based on nearest neighbour data), physiology (levels of excreted corticosterone metabolites assayed from droppings), and agonistic interactions in a group of free-ranging greylag geese (Anser anser). Forty-four greylag geese below 3 years of age were observed in three different seasonal phases: during the re-aggregation of the flock in autumn, at the end of the winter and during the forthcoming breeding season. We show that corticosterone metabolite levels and initiated and received aggression increased with increasing social connectivity. Individuals had higher connectivity scores in the winter flock than during the mating and breeding seasons. One-year old juveniles were more connected than 2- and 3-year old individuals. In addition, we examined the link between social connectivity during early development and reproductive success several years later. We found that birds with greater connectivity early in life attempted to breed at a younger age. Furthermore, successful breeders with higher early connectivity scores had higher numbers of fledged goslings. Our results show that social context in early life stages may have long-term effects on individual fitness.
群居生活对群体成员既有好处也有坏处。我们研究了自由放养的灰雁群体中早期社会联系（基于最近邻数据的归一化弗里曼度数）、生理学（从粪便中检测到的排泄皮质酮代谢物水平）和争斗行为对适应度的影响。在三个不同的季节阶段观察了 44 只年龄在 3 岁以下的灰雁：在秋季群体重新聚集时、冬季结束时和即将到来的繁殖季节。我们表明，皮质酮代谢物水平以及发起和接受攻击的次数随着社会联系的增加而增加。个体在冬季群体中的连接得分高于交配和繁殖季节。1 岁的幼鸟比 2 岁和 3 岁的个体连接得分更高。此外，我们还研究了早年发展过程中的社交联系与数年后繁殖成功之间的关系。我们发现，早年生活中连接得分更高的鸟类尝试更早繁殖。此外，早期连接得分较高的成功繁殖者有更多的幼鹅。我们的研究结果表明，早期生活阶段的社会环境可能对个体的适应度产生长期影响。
