School of Biological Sciences, University of Aberdeen, King's College, Aberdeen, AB24 3FX, U.K.
Department of Animal Sciences, Purdue University, West Lafayette, IN, 47907, U.S.A.
Biol Rev Camb Philos Soc. 2021 Dec;96(6):2661-2693. doi: 10.1111/brv.12772. Epub 2021 Jul 2.
Social interactions are ubiquitous across the animal kingdom. A variety of ecological and evolutionary processes are dependent on social interactions, such as movement, disease spread, information transmission, and density-dependent reproduction and survival. Social interactions, like any behaviour, are context dependent, varying with environmental conditions. Currently, environments are changing rapidly across multiple dimensions, becoming warmer and more variable, while habitats are increasingly fragmented and contaminated with pollutants. Social interactions are expected to change in response to these stressors and to continue to change into the future. However, a comprehensive understanding of the form and magnitude of the effects of these environmental changes on social interactions is currently lacking. Focusing on four major forms of rapid environmental change currently occurring, we review how these changing environmental gradients are expected to have immediate effects on social interactions such as communication, agonistic behaviours, and group formation, which will thereby induce changes in social organisation including mating systems, dominance hierarchies, and collective behaviour. Our review covers intraspecific variation in social interactions across environments, including studies in both the wild and in laboratory settings, and across a range of taxa. The expected responses of social behaviour to environmental change are diverse, but we identify several general themes. First, very dry, variable, fragmented, or polluted environments are likely to destabilise existing social systems. This occurs as these conditions limit the energy available for complex social interactions and affect dissimilar phenotypes differently. Second, a given environmental change can lead to opposite responses in social behaviour, and the direction of the response often hinges on the natural history of the organism in question. Third, our review highlights the fact that changes in environmental factors are not occurring in isolation: multiple factors are changing simultaneously, which may have antagonistic or synergistic effects, and more work should be done to understand these combined effects. We close by identifying methodological and analytical techniques that might help to study the response of social interactions to changing environments, highlight consistent patterns among taxa, and predict subsequent evolutionary change. We expect that the changes in social interactions that we document here will have consequences for individuals, groups, and for the ecology and evolution of populations, and therefore warrant a central place in the study of animal populations, particularly in an era of rapid environmental change.
社会互动在动物界无处不在。各种生态和进化过程都依赖于社会互动，如运动、疾病传播、信息传递以及密度依赖的繁殖和生存。与任何行为一样，社会互动也是依赖于环境条件的，会随环境条件的变化而变化。目前，环境在多个维度上迅速变化，变得更加温暖和多变，而栖息地则越来越碎片化，并受到污染物的污染。预计社会互动将对这些压力源做出反应，并在未来继续变化。然而，对于这些环境变化对社会互动的形式和程度的影响，目前还缺乏全面的了解。本文聚焦于目前正在发生的四种主要形式的快速环境变化，综述了这些不断变化的环境梯度如何对社会互动（如通讯、攻击行为和群体形成）产生直接影响，从而导致社会组织的变化，包括交配系统、支配等级和集体行为。我们的综述涵盖了跨环境的种内社会互动的变化，包括野外和实验室研究以及跨多个分类群的研究。社会行为对环境变化的预期反应是多种多样的，但我们确定了几个一般主题。首先，非常干燥、多变、碎片化或污染的环境可能会破坏现有的社会系统。这是因为这些条件限制了进行复杂社会互动的可用能量，并对不同的表型产生不同的影响。其次，给定的环境变化可能导致社会行为产生相反的反应，而反应的方向往往取决于所研究的生物体的自然历史。第三，我们的综述强调了一个事实，即环境因素的变化不是孤立发生的：多个因素同时发生变化，这些变化可能具有拮抗或协同作用，应该做更多的工作来理解这些综合效应。最后，我们确定了一些可能有助于研究社会互动对不断变化的环境的反应的方法和分析技术，突出了分类群之间的一致模式，并预测了随后的进化变化。我们预计，我们在这里记录的社会互动的变化将对个体、群体以及种群的生态和进化产生影响，因此应该在动物种群的研究中占据中心位置，特别是在快速环境变化的时代。
