The adaptation of populations to changing conditions may be affected by interactions between individuals. For example, when cooperative interactions increase fecundity, they may allow populations to maintain high densities and thus keep track of moving environmental optima. Simultaneously, changes in population density alter the marginal benefits of cooperative investments, creating a feedback loop between population dynamics and the evolution of cooperation. Here we model how the evolution of cooperation interacts with adaptation to changing environments. We hypothesize that environmental change lowers population size and thus promotes the evolution of cooperation, and that this, in turn, helps the population keep up with the moving optimum. However, we find that the evolution of cooperation can have qualitatively different effects, depending on which fitness component is reduced by the costs of cooperation. If the costs decrease fecundity, cooperation indeed speeds adaptation by increasing population density; if, in contrast, the costs decrease viability, cooperation may instead slow adaptation by lowering the effective population size, leading to evolutionary suicide. Thus, cooperation can either promote or—counterintuitively—hinder adaptation to a changing environment. Finally, we show that our model can also be generalized to other social interactions by discussing the evolution of competition during environmental change.

中文翻译：

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合作可以在环境变化期间促进救援或导致进化自杀

种群对不断变化的条件的适应可能会受到个体之间相互作用的影响。例如，当合作互动增加繁殖力时，它们可能使种群保持高密度，从而跟踪移动的环境优化。同时，人口密度的变化改变了合作投资的边际收益，在人口动态和合作演变之间形成了一个反馈回路。在这里，我们模拟了合作的演变如何与对不断变化的环境的适应相互作用。我们假设环境变化降低了人口规模，从而促进了合作的演变，而这反过来又有助于人口跟上移动的最优。然而，我们发现合作的演变可以产生质的不同影响，取决于合作成本减少了哪个健身成分。如果成本会降低繁殖力，那么合作确实会通过增加人口密度来加速适应；相反，如果成本降低了生存能力，合作可能会通过降低有效种群规模来减缓适应，导致进化自杀。因此，合作可以促进或违反直觉地阻碍对不断变化的环境的适应。最后，我们通过讨论环境变化期间竞争的演变，表明我们的模型也可以推广到其他社会互动。相反，合作可能会通过降低有效种群规模来减缓适应，导致进化自杀。因此，合作可以促进或违反直觉地阻碍对不断变化的环境的适应。最后，我们通过讨论环境变化期间竞争的演变，表明我们的模型也可以推广到其他社会互动。相反，合作可能会通过降低有效种群规模来减缓适应，导致进化自杀。因此，合作可以促进或违反直觉地阻碍对不断变化的环境的适应。最后，我们通过讨论环境变化期间竞争的演变，表明我们的模型也可以推广到其他社会互动。