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A fishy perspective on the social brain hypothesis

Published online by Cambridge University Press:  27 November 2025

Redouan Bshary Open the ORCID record for Redouan Bshary [Opens in a new window]  and
Zegni Triki Open the ORCID record for Zegni Triki [Opens in a new window]
Redouan Bshary*
Affiliation:
Institute of Biology, University of Neuchatel, Neuchatel, Switzerland redouan.bshary@unine.ch zegni.triki@unine.ch https://www.unine.ch/ethol/
Zegni Triki
Affiliation:
Institute of Biology, University of Neuchatel, Neuchatel, Switzerland redouan.bshary@unine.ch zegni.triki@unine.ch https://www.unine.ch/ethol/
*
*Corresponding author.
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Abstract

Ectotherms, particularly fish, challenge traditional brain evolution theories by exhibiting advanced cognitive abilities despite their smaller brains. While the social brain hypothesis may apply within clades, sensory-motor systems likely explain the brain size differences between average-brained ectotherms and endotherms. Evolved complex sensory-motor systems suggest that brain evolution models should expand to include sensory and motor systems, beyond cognitive processes alone.

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Open Peer Commentary
Information
Behavioral and Brain Sciences , Volume 48 , 2025 , e166
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Copyright
© The Author(s), 2025. Published by Cambridge University Press

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Footnotes

Redouan Bshary and Zegni Triki contributed equally to this work.

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