For most of our species’ history, humans have lived in relatively small subsistence communities, often called small-scale societies. While these groups lack centralized institutions, they can and often do maintain large-scale cooperation. Here, we explore several mechanisms promoting cooperation in small-scale societies, including (a) the development of social norms that encourage prosocial behavior, (b) reciprocal exchange relationships, (c) reputation that facilitates high-cost cooperation, (d) relational wealth, and (e) risk buffering institutions. We illustrate these with ethnographic and psychological evidence from contemporary small-scale societies. We argue that these mechanisms for cooperation helped past and present small-scale communities adapt to diverse ecological and social niches.

在我们物种的大部分历史中，人类一直生活在相对较小的生存社区，通常被称为小规模社会。虽然这些团体缺乏中央机构，但他们可以而且经常确实保持大规模合作。在这里，我们探讨了在小规模社会中促进合作的几种机制，包括（a）鼓励亲社会行为的社会规范的发展，（b）互惠交换关系，（c）促进高成本合作的声誉，（d）关系财富，以及 (e) 风险缓冲机构。我们用当代小规模社会的民族志和心理学证据来说明这些。我们认为，这些合作机制帮助过去和现在的小规模社区适应不同的生态和社会环境。