Sex-independent senescence in a cooperatively breeding mammal

1. Researchers studying mammals have frequently interpreted earlier or faster rates of ageing in males as resulting from polygyny and the associated higher costs of reproductive competition. 2. Yet few studies conducted on wild populations have compared sex-specific senescence trajectories outside of polygynous species, making it difficult to make generalised inferences on the role of reproductive competition in driving senescence, particularly when other differences between males and females might also contribute to sex-specific changes in performance across lifespan. 3. Here, we examine age-related variation in body mass, reproductive output and survival in dominant male and female meerkats, Suricata suricatta. Meerkats are socially monogamous cooperative breeders where a single dominant pair virtually monopolize reproduction in each group and subordinate group members help to rear offspring produced by breeders. 4. In contrast to many polygynous societies, we find that neith...1. 从事哺乳动物研究的科研人员常将雄性衰老速率更早、更快的现象，归因于一夫多妻制（polygyny）以及由此引发的繁殖竞争所带来的更高成本。 2. 然而，针对野生种群的现有研究中，极少有在一夫多妻类物种之外开展性别特异性衰老轨迹比较的工作，这使得我们难以就繁殖竞争在驱动衰老过程中的作用得出普适性推论——尤其是当雌雄两性间还存在其他差异，也可能对其整个寿命周期内的机能表现带来性别特异性变化时。 3. 本研究针对狐獴（Suricata suricatta）优势雌雄个体的体重、繁殖产出与存活情况的年龄相关变异展开分析。狐獴属于社会单配制合作繁殖物种，每个集群内仅存在一对优势繁殖对，几乎独占所有繁殖机会，集群中的从属个体则会协助抚育繁殖对产下的后代。 4. 与诸多一夫多妻制社会截然不同的是，我们发现二者均未……