Cooperation among non-kin is well documented in humans and widespread in non-human animals, but explaining the occurrence of cooperation in the absence of inclusive fitness benefits has proven a significant challenge. Current theoretical explanations converge on a single point: cooperators can prevail when they cluster in social space. However, we know very little about the real-world mechanisms that drive such clustering, particularly in systems where cognitive limitations make it unlikely that mechanisms such as score keeping and reputation are at play. Here, we show that Trinidadian guppies (Poecilia reticulata) use a ‘walk away’ strategy, a simple social heuristic by which assortment by cooperativeness can come about among mobile agents. Guppies cooperate during predator inspection and we found that when experiencing defection in this context, individuals prefer to move to a new social environment, despite having no prior information about this new social group. Our results provide evidence in non-human animals that individuals use a simple social partner updating strategy in response to defection, supporting theoretical work applying heuristics to understanding the proximate mechanisms underpinning the evolution of cooperation among non-kin.

中文翻译：

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特立尼达孔雀鱼使用一种社会启发式方法，可以支持非亲属之间的合作

非亲属之间的合作在人类中得到了很好的记录，在非人类动物中也很普遍，但在缺乏包容性健身益处的情况下解释合作的发生已被证明是一项重大挑战。当前的理论解释集中在一个点上：合作者在社会空间中聚集时可以占上风。然而，我们对驱动这种聚类的现实世界机制知之甚少，特别是在认知限制使得记分和声誉等机制不太可能发挥作用的系统中。在这里，我们展示了特立尼达孔雀鱼（Poecilia reticulata）使用“走开”策略，这是一种简单的社会启发式方法，通过这种方法可以在移动代理之间进行合作分类。孔雀鱼在捕食者检查期间合作，我们发现在这种情况下经历叛逃时，尽管没有关于这个新社会群体的先验信息，个人更愿意搬到一个新的社会环境。我们的结果在非人类动物中提供了证据，表明个体使用简单的社会伙伴更新策略来应对背叛，支持应用启发式方法来理解支持非亲属之间合作演变的直接机制的理论工作。