A meta-analysis of the association between male dimorphism and fitness outcomes in humans
Abstract
Humans are sexually dimorphic: men and women differ in body build and composition, craniofacial structure, and voice pitch, likely mediated in part by developmental testosterone. Sexual selection hypotheses posit that, ancestrally, more 'masculine' men may have acquired more mates and/or sired more viable offspring. Thus far, however, evidence for either association is unclear. Here, we meta-analyze the relationships between six masculine traits and mating/reproductive outcomes (96 studies, 474 effects, N = 177,044). Voice pitch, height, and testosterone all predicted mating; however, strength/muscularity was the strongest and only consistent predictor of both mating and reproduction. Facial masculinity and digit ratios did not significantly predict either. There was no clear evidence for any effects of masculinity on offspring viability. Our findings support arguments that strength/muscularity may be sexually selected in humans, but cast doubt regarding selection for other forms of masculinity and highlight the need to increase tests of evolutionary hypotheses outside of industrialized populations.
Data availability
All data generated and analysed in this article, including complete R code, are available on the Open Science Framework.LH Lidborg, CP Cross & LG Boothroyd (2020)Is male dimorphism under sexual selection in humans? A meta-analysishttps://doi.org/10.17605/OSF.IO/PHC4X
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The authors declare that there was no funding for this work.
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© 2022, Lidborg et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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