Department of Biology, Lund University, Lund, Sweden.
Elife. 2021 Jul 26;10:e66649. doi: 10.7554/eLife.66649.
Living with relatives can be highly beneficial, enhancing reproduction and survival. High relatedness can, however, increase susceptibility to pathogens. Here, we examine whether the benefits of living with relatives offset the harm caused by pathogens, and if this depends on whether species typically live with kin. Using comparative meta-analysis of plants, animals, and a bacterium ( = 56), we show that high within-group relatedness increases mortality when pathogens are present. In contrast, mortality decreased with relatedness when pathogens were rare, particularly in species that live with kin. Furthermore, across groups variation in mortality was lower when relatedness was high, but abundances of pathogens were more variable. The effects of within-group relatedness were only evident when pathogens were experimentally manipulated, suggesting that the harm caused by pathogens is masked by the benefits of living with relatives in nature. These results highlight the importance of kin selection for understanding disease spread in natural populations.
与亲属生活在一起可能有很多好处，可以提高繁殖和生存能力。然而，高亲缘关系会增加对病原体的易感性。在这里，我们研究了与亲属生活在一起的好处是否可以抵消病原体造成的伤害，以及这是否取决于物种是否通常与亲属生活在一起。通过对植物、动物和一种细菌（=56）的比较荟萃分析，我们发现当存在病原体时，高群体内亲缘关系会增加死亡率。相比之下，当病原体稀少时，亲缘关系的增加会降低死亡率，特别是在与亲属生活在一起的物种中。此外，当亲缘关系较高时，各组之间的死亡率变化较小，而病原体的丰度变化较大。只有当病原体被实验操纵时，群体内亲缘关系的影响才明显，这表明在自然界中，与亲属生活在一起的好处掩盖了病原体造成的危害。这些结果强调了亲属选择对于理解自然种群中疾病传播的重要性。
