Social norms promote cooperation in human groups. How are these norms and cooperation affected when groups change due to new members arriving and old members leaving? In this review we highlight the scant literature that researches the effects of group changes on social norms and cooperation. Thus far evidence suggests that newcomers cooperate less than incumbents but adjust their cooperation levels over time. However, this adjustment is not necessarily accompanied by adjustments in terms of group identification and norms. We also point to the data limitations that ensue when researching phenomena at the group level and outline future research directions.

中文翻译：

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不断变化的群体中的社会规范动态和合作


社会规范促进人类群体的合作。当团体由于新成员的加入和老成员的离开而发生变化时，这些规范和合作会受到怎样的影响？在这篇综述中，我们强调了研究群体变化对社会规范和合作影响的文献很少。迄今为止的证据表明，新来者的合作程​​度低于现有企业，但会随着时间的推移调整合作水平。但这种调整并不一定伴随着群体认同和规范方面的调整。我们还指出了在群体层面研究现象时随之而来的数据限制，并概述了未来的研究方向。