Social life histories: jackdaw dominance increases with age, terminally declines and shortens lifespan

Verhulst, S., Geerdink, M., Salomons, H. M. and Boonekamp, J. J. (2014) Social life histories: jackdaw dominance increases with age, terminally declines and shortens lifespan. Proceedings of the Royal Society of London Series B: Biological Sciences, 281(1791), 20141045. (doi: 10.1098/rspb.2014.1045) (PMID:25100696) (PMCID:PMC4132676)

Abstract

Behaviour may contribute to changes in fitness prospects with age, for example through effects of age-dependent social dominance on resource access. Older individuals often have higher dominance rank, which may reflect a longer lifespan of dominants and/or an increase in social dominance with age. In the latter case, increasing dominance could mitigate physiological senescence. We studied the social careers of free-living jackdaws over a 12 year period, and found that: (i) larger males attained higher ranks, (ii) social rank increased with age within individuals, and (iii) high-ranked individuals had shorter lifespan suggesting that maintaining or achieving high rank and associated benefits comes at a cost. Lastly, (iv) social rank declined substantially in the last year an individual was observed in the colony, and through its effect on resource access this may accelerate senescence. We suggest that behaviour affecting the ability to secure resources is integral to the senescence process via resource effects on somatic state, where behaviour may include not only social dominance, but also learning, memory, perception and (sexual) signalling. Studying behavioural effects on senescence via somatic state may be most effective in the wild, where there is competition for resources, which is usually avoided in laboratory conditions.

• Item Type: Articles
• Additional Information: H.M.S was supported by an NWO Vici grant to S.V..
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Boonekamp, Dr Jelle
• Authors: Verhulst, S., Geerdink, M., Salomons, H. M., and Boonekamp, J. J.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Proceedings of the Royal Society of London Series B: Biological Sciences
• Publisher: The Royal Society
• ISSN: 0962-8452
• ISSN (Online): 1471-2954