The contribution of sexual selection to brain evolution has been little investigated. Through comparative analyses of bats, we show that multiple mating by males, in the absence of multiple mating by females, has no evolutionary impact on relative brain dimension. In contrast, bat species with promiscuous females have relatively smaller brains than do species with females exhibiting mate fidelity. This pattern may be a consequence of the demonstrated negative evolutionary relationship between investment in testes and investment in brains, both metabolically expensive tissues. These results have implications for understanding the correlated evolution of brains, behaviour and extravagant sexually selected traits.

Footnotes

†Present address: Institute of Zoology, Zoological Society of London, Regents Park, London NW1 4RY, UK.

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Proceedings of the Royal Society B: Biological Sciences cover image

22 March 2006

Volume 273Issue 1587

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DOI:https://doi.org/10.1098/rspb.2005.3367
PubMed:16608692
Published by:Royal Society
Print ISSN:0962-8452
Online ISSN:1471-2954

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Manuscript received14/09/2005
Manuscript accepted10/10/2005
Published online06/12/2005
Published in print22/03/2006

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