Altruistic bet-hedging and the evolution of cooperation in a Kalahari bird

Capilla Lasheras, P. , Harrison, X., Wood, E. M., Wilson, A. J. and Young, A. J. (2021) Altruistic bet-hedging and the evolution of cooperation in a Kalahari bird. Science Advances, 7(39), eabe8980. (doi: 10.1126/sciadv.abe8980) (PMID:34550732) (PMCID:PMC8457656)

Abstract

Altruism is globally associated with unpredictable environments, but we do not understand why. New theory has highlighted that unpredictable environments could favor the evolution of altruism if altruistic acts reduce environmentally induced variance in the reproductive success of relatives (“altruistic bet-hedging”). Here, we show that altruism does indeed reduce environmentally induced reproductive variance in a wild cooperative bird. Our decade-long field study reveals that altruistic helping actually has no overall effect on the mean reproductive success of relatives but instead reduces their reproductive variance. This remarkable pattern arises because helpers improve reproductive performance in dry conditions but reduce it in wet conditions. Helpers thereby specifically reduce rainfall-induced reproductive variance, the very mechanism required for altruistic bet-hedging to explain the enigmatic global association between avian altruism and unpredictable rainfall.

• Item Type: Articles
• Additional Information: The long-term field study was funded by BBSRC David Phillips and NERC Blue Skies Research Fellowships to A.J.Y. (BB/H022716/1 and NE/E013481/1). P.C.-L. and E.M.W. were supported by BBSRC-funded PhD studentships (BB/M009122/1 and BB/J014400/1).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Capilla Lasheras, Dr Pablo
• Authors: Capilla Lasheras, P., Harrison, X., Wood, E. M., Wilson, A. J., and Young, A. J.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Science Advances
• Publisher: American Association for the Advancement of Science
• ISSN: 2375-2548
• ISSN (Online): 2375-2548
• Copyright Holders: Copyright © 2021 The Authors
• First Published: First published in Science Advances 7(39):eabe8980
• Publisher Policy: Reproduced under a Creative Commons License