Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9712 CP, Groningen, The Netherlands.
Department of Animal Science, Wageningen University & Research, 6708 PB, Wageningen, The Netherlands.
Nat Commun. 2019 Mar 21;10(1):1301. doi: 10.1038/s41467-019-09229-3.
Helping by group members is predicted to lead to delayed senescence by affecting the trade-off between current reproduction and future survival for dominant breeders. Here we investigate this prediction in the Seychelles warbler, Acrocephalus sechellensis, in which mainly female subordinate helpers (both co-breeders and non-breeding helpers) often help dominants raise offspring. We find that the late-life decline in survival usually observed in this species is greatly reduced in female dominants when a helper is present. Female dominants with a female helper show reduced telomere attrition, a measure that reflects biological ageing in this and other species. Finally, the probability of having female, but not male, helpers increases with dominant female age. Our results suggest that delayed senescence is a key benefit of cooperative breeding for elderly dominants and support the idea that sociality and delayed senescence are positively self-reinforcing. Such an effect may help explain why social species often have longer lifespans.
群体成员的帮助预计会通过影响当前繁殖和未来生存之间的权衡，从而导致优势繁殖者的衰老延迟。在这里，我们在塞舌尔莺（Acrocephalus sechellensis）中研究了这一预测，在这种鸟类中，主要是雌性从属助手（共同繁殖者和非繁殖助手）经常帮助优势种繁殖后代。我们发现，在这个物种中通常观察到的晚年生存下降在有帮手时大大减少了雌性优势种。当有雌性助手时，具有雌性助手的雌性优势种表现出减少的端粒磨损，这一指标反映了该物种和其他物种的生物衰老。最后，雌性助手（而非雄性助手）出现的概率随着优势种雌性年龄的增加而增加。我们的结果表明，衰老延迟是合作繁殖对老年优势种的关键益处，并支持社会性和衰老延迟相互促进的观点。这种影响可能有助于解释为什么社会性物种通常寿命更长。
