Morrison Robin E, Eckardt Winnie, Colchero Fernando, Vecellio Veronica, Stoinski Tara S
Dian Fossey Gorilla Fund, Musanze, Rwanda.
Centre for Research in Animal Behaviour, University of Exeter, Exeter, United Kingdom.
Elife. 2021 Mar 23;10:e62939. doi: 10.7554/eLife.62939.
Mothers are crucial for mammals' survival before nutritional independence, but many social mammals reside with their mothers long after. In these species the social adversity caused by maternal loss later in life can dramatically reduce fitness. However, in some human populations these negative consequences can be overcome by care from other group members. We investigated the consequences of maternal loss in mountain gorillas and found no discernible fitness costs to maternal loss through survival, age at first birth, or survival of first offspring through infancy. Social network analysis revealed that relationships with other group members, particularly dominant males and those close in age, strengthened following maternal loss. In contrast to most social mammals, where maternal loss causes considerable social adversity, in mountain gorillas, as in certain human populations, this may be buffered by relationships within cohesive social groups, breaking the link between maternal loss, increased social adversity, and decreased fitness.
在营养独立之前，母亲对于哺乳动物的生存至关重要，但许多群居哺乳动物在营养独立之后仍会与母亲长期生活在一起。在这些物种中，母亲在后期生活中丧失所带来的社会逆境会显著降低适应性。然而，在一些人类群体中，这些负面后果可以通过其他群体成员的照顾来克服。我们研究了山地大猩猩母亲丧失的后果，发现通过生存、首次生育年龄或首个后代在婴儿期的生存情况来看，母亲丧失并没有明显的适应性代价。社会网络分析表明，母亲丧失后，与其他群体成员的关系，特别是与占主导地位的雄性以及年龄相近的个体的关系得到了加强。与大多数群居哺乳动物不同，在大多数群居哺乳动物中，母亲丧失会导致相当大的社会逆境，而在山地大猩猩中，如同在某些人类群体中一样，这可能会被紧密社会群体中的关系所缓冲，从而打破母亲丧失、社会逆境增加和适应性降低之间的联系。
