Borgeaud Christèle, Sosa Sebastian, Bshary Redouan, Sueur Cédric, van de Waal Erica
Laboratory of Eco-Ethology, Institute of Biology, University of NeuchâtelNeuchâtel, Switzerland; Inkawu Vervet Project, Mawana Game ReserveKwaZulu Natal, South Africa.
Adaptive Behavior and Interaction Research Group, University of Barcelona Barcelona, Spain.
Front Psychol. 2016 Jun 21;7:915. doi: 10.3389/fpsyg.2016.00915. eCollection 2016.
Social network analysis is a powerful tool that enables us to describe and quantify relationships between individuals. So far most of the studies rely on the analyses of various network snapshots, but do not capture changes over time. Here we use a stochastic actor-oriented model (SAOM) to test both the structure and the dynamics of relationships of three groups of wild vervet monkeys. We found that triadic closure (i.e., the friend of a friend is a friend) was significant in all three groups while degree popularity (i.e., the willingness to associate with individuals with high degree of connections) was significant in only two groups (AK, BD). The structure and dynamics of relationships according to the attributes of sex, matrilineand age differed significantly among groups. With respect to the structure, when analyzing the likelihood of bonds according to the different attributes, we found that individuals associate themselves preferably to individuals of the same sex only in two groups (AK, NH), while significant results for attachment to individuals of the same matriline were found also in two groups (BD, NH). With respect to the dynamics, i.e., how quickly relationships are modified, we found in two groups (AK, BD) that females' relationships were more prone to variation than males.' In the BD group, relationships within high-ranking matrilines were less stable than low-ranking ones while in the NH group, juveniles' relationships were also less stable than adults' ones. The intergroup variation indicates that establishing species-specific or even population specific characteristics of social networks for later between-species comparisons will be challenging. Although, such variation could also indicate some methodological issue, we are quite confident that data was collected similarly within the different groups. Our study therefore provides a potential new method to quantify social complexity according to natural demographic variation.
社会网络分析是一种强大的工具，它使我们能够描述和量化个体之间的关系。到目前为止，大多数研究依赖于对各种网络快照的分析，但没有捕捉到随时间的变化。在这里，我们使用一个面向随机行动者的模型（SAOM）来测试三组野生绿猴关系的结构和动态。我们发现，三元闭合（即朋友的朋友也是朋友）在所有三组中都很显著，而度受欢迎程度（即与高连接度个体交往的意愿）仅在两组（AK、BD）中显著。根据性别、母系和年龄属性的关系结构和动态在不同组之间存在显著差异。关于结构，在根据不同属性分析联系的可能性时，我们发现只有两组（AK、NH）中的个体更倾向于与同性个体建立联系，而在两组（BD、NH）中也发现了与同母系个体建立联系的显著结果。关于动态，即关系变化的速度，我们在两组（AK、BD）中发现，雌性的关系比雄性更容易发生变化。在BD组中，高等级母系内的关系比低等级母系内的关系更不稳定，而在NH组中，幼年个体的关系也比成年个体的关系更不稳定。组间差异表明，为后续物种间比较建立特定物种甚至特定种群的社会网络特征将具有挑战性。虽然这种差异也可能表明一些方法学问题，但我们非常确信不同组内的数据收集方式是相似的。因此，我们的研究提供了一种潜在的新方法，可根据自然人口统计学差异来量化社会复杂性。
