Mammals living in more complex social groups typically have large brains for their body size and many researchers have proposed that the primary driver of the increase in brain size through primate and hominin evolution was the selection pressures associated with sociality. Many mammals, and especially primates, use flexible signals that show a high degree of voluntary control and these signals may play an important role in forming and maintaining social relationships between group members. However, the specific role that cognitive skills play in this complex communication, and how in turn this relates to sociality, is still unclear. The hypothesis for the communicative roots of complex sociality and cognition posits that cognitive demands behind the communication needed to form and maintain bonded social relationships in complex social settings drives the link between brain size and sociality. We review the evidence in support of this hypothesis and why key features of cognitively complex communication such as intentionality and referentiality should be more effective in forming and maintaining bonded relationships as compared with less cognitively complex communication. Exploring the link between cognition, communication and sociality provides insights into how increasing flexibility in communication can facilitate the emergence of social systems characterised by bonded social relationships, such as those found in non‐human primates and humans. To move the field forward and carry out both within‐ and among‐species comparisons, we advocate the use of social network analysis, which provides a novel way to describe and compare social structure. Using this approach can lead to a new, systematic way of examining social and communicative complexity across species, something that is lacking in current comparative studies of social structure.

中文翻译：

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复杂社会性和认知的交际根源

生活在更复杂的社会群体中的哺乳动物通常拥有相对于体型而言较大的大脑，许多研究人员提出，通过灵长类动物和人类进化，大脑体积增加的主要驱动力是与社会性相关的选择压力。许多哺乳动物，尤其是灵长类动物，使用灵活的信号来显示高度的自愿控制，这些信号可能在形成和维持群体成员之间的社会关系方面发挥重要作用。然而，认知技能在这种复杂的交流中所起的具体作用，以及这又如何与社会性相关，仍不清楚。复杂社会性和认知的交流根源假说认为，在复杂社会环境中形成和维持紧密社会关系所需的交流背后的认知需求推动了大脑大小和社会性之间的联系。我们回顾了支持这一假设的证据，以及为什么与认知复杂性较低的交流相比，意向性和指称性等认知复杂交流的关键特征在形成和维持联系关系方面应该更有效。探索认知、交流和社会性之间的联系，可以深入了解提高交流灵活性如何促进以紧密社会关系为特征的社会系统的出现，例如在非人类灵长类动物和人类中发现的社会系统。为了推动该领域的发展并进行种内和种间比较，我们提倡使用社会网络分析，它提供了一种描述和比较社会结构的新方法。使用这种方法可以产生一种新的、系统的方法来检查跨物种的社会和交流复杂性，这是当前社会结构比较研究所缺乏的。