Department of Integrative Biology, University of Guelph, 50 Stone Rd E, Guelph, ON, N1G 2W1, CA; Centre for Research in Animal Behaviour, School of Psychology, University of Exeter, Stocker Rd, Exeter, EX4 4PY, UK.
Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, AB, T6G 2E9, CA.
Curr Biol. 2021 Jan 25;31(2):438-445.e3. doi: 10.1016/j.cub.2020.10.072. Epub 2020 Dec 18.
One of the outstanding questions in evolutionary biology is the extent to which mutually beneficial interactions and kin selection can facilitate the evolution of cooperation by mitigating conflict between interacting organisms. The indirect fitness benefits gained from associating with kin are an important pathway to conflict resolution, but conflict can also be resolved if individuals gain direct benefits from cooperating with one another (e.g., mutualism or reciprocity). Because of the kin-structured nature of many animal societies, it has been difficult for previous research to assess the relative importance of these mechanisms. However, one area that might allow for the relative roles of kin selection and mutualistic benefits to be disentangled is in the resolution of conflict over territorial space. Although much research has focused on group-living species, the question of how cooperation can first be favored in solitary, territorial species remains a key question. Using 22 years of data from a population of North American red squirrels, we assessed how kinship and familiarity with neighbors affected fitness in a territorial mammal. Although living near kin did not enhance fitness, familiarity with neighbors increased survival and annual reproductive success. These fitness benefits were strong enough to compensate for the effects of aging later in life and have potential consequences for the evolution of senescence. We suggest that such substantial fitness benefits provide the opportunity for the evolution of cooperation between adversarial neighbors, offering insight into the role that mutually beneficial behaviors might play in facilitating and stabilizing social systems.
进化生物学中的一个突出问题是，互利相互作用和亲属选择在多大程度上可以通过减轻相互作用的生物体之间的冲突来促进合作的进化。与亲属相关联所获得的间接适合度利益是解决冲突的重要途径，但如果个体从相互合作中直接获得利益（例如，互惠或相互作用），也可以解决冲突。由于许多动物社会具有亲属结构的性质，因此以前的研究很难评估这些机制的相对重要性。然而，一个可能允许区分亲属选择和互利利益的相对作用的领域是在解决领土空间冲突方面。尽管许多研究都集中在群体生活的物种上，但合作如何首先在独居、有领土的物种中得到青睐仍然是一个关键问题。我们使用了 22 年来自北美的红松鼠种群的数据，评估了亲缘关系和与邻居的熟悉程度如何影响领地哺乳动物的适应度。尽管与亲属居住在一起并没有提高适应度，但与邻居的熟悉程度增加了生存和年生殖成功率。这些适应度利益足以弥补晚年衰老的影响，并对衰老的进化产生潜在影响。我们认为，这种实质性的适应度利益为敌对邻居之间合作的进化提供了机会，为互利行为在促进和稳定社会系统中可能发挥的作用提供了新的认识。
