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Spelling out the mechanism: functional support and modified stressor appraisal buffer a cost of increased group size

Published online by Cambridge University Press:  27 November 2025

Julia Ostner Open the ORCID record for Julia Ostner [Opens in a new window]  and
Oliver Schülke Open the ORCID record for Oliver Schülke [Opens in a new window]
Julia Ostner*
Affiliation:
Department for Behavioral Ecology, Georg-August University of Göttingen, Göttingen, Germany jostner@gwdg.de Primate Social Evolution Group, German Primate Center, Leibniz-Institute for Primate Research, Göttingen, Germany oschuel@gwdg.de https://www.dpz.eu/en/social-evolution-in-primates
Oliver Schülke
Affiliation:
Department for Behavioral Ecology, Georg-August University of Göttingen, Göttingen, Germany jostner@gwdg.de Primate Social Evolution Group, German Primate Center, Leibniz-Institute for Primate Research, Göttingen, Germany oschuel@gwdg.de https://www.dpz.eu/en/social-evolution-in-primates
*
*Corresponding author.
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Abstract

Dunbar suggests structural, behavioral, and cognitive mechanisms to mitigate the costs of living in large groups. While we generally concur with the notion of group size effects on female productivity, we call for a more explicit treatment of how functional support alleviates social costs and disagree with the outright dismissal of ecological drivers and phylogenetic inertia.

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Type
Open Peer Commentary
Information
Behavioral and Brain Sciences , Volume 48 , 2025 , e177
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Copyright
© The Author(s), 2025. Published by Cambridge University Press

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