Family network size and survival across the lifespan of female macaques
Proceedings of the Royal Society B: Biological Sciences
© 2017 The Author(s) http://royalsocietypublishing.org/licence Published by the Royal Society. All rights reserved.
Reason for embargo
Two decades of research suggest social relationships have a common evolutionary basis in humans and other gregarious mammals. Critical to the support of this idea is growing evidence that mortality is influenced by social integration, but when these effects emerge and how long they last is mostly unknown. Here, we report in adult female macaques that the impact of number of close adult female relatives, a proxy for social integration, on survival is not experienced uniformly across the life course; prime-aged females with a greater number of relatives had better survival outcomes compared with prime-aged females with fewer relatives, whereas no such effect was found in older females. Group size and dominance rank did not influence this result. Older females were less frequent targets of aggression, suggesting enhanced experience navigating the social landscape may obviate the need for social relationships in old age. Only one study of humans has found age-based dependency in the association between social integration and survival. Using the largest dataset for any non-human animal to date, our study extends support for the idea that sociality promotes survival and suggests strategies employed across the life course change along with experience of the social world.
This work was supported by NIMH grants no. R01-MH096875 and R01-MH089484 to M.L.P. and L.J.N.B., and by a Leverhulme Early Career Fellowship to L.J.N.B. The CPRC is supported by grant no. 2P40OD012217 from the National Center for Research Resources (NCRR) and the Office of Research Infrastructure Programs (ORIP) of the National Institutes of Health.
This is the author accepted manuscript. The final version is available from the Royal Society via the DOI in this record.
, Vol. 284, pp. 20170515 - 20170515