A meta-analysis of the association between male dimorphism and fitness outcomes in humans

  1. Linda H Lidborg  Is a corresponding author
  2. Catharine Penelope Cross
  3. Lynda G Boothroyd
  1. Durham University, United Kingdom
  2. University of St Andrews, United Kingdom

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

Article and author information

Author details

  1. Linda H Lidborg

    Department of Psychology, Durham University, Durham, United Kingdom
    For correspondence
    lhlidborg@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9667-9326
  2. Catharine Penelope Cross

    School of Psychology and Neuroscience, University of St Andrews, St Andrews, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8110-8408
  3. Lynda G Boothroyd

    Department of Psychology, Durham University, Durham, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

Funding

The authors declare that there was no funding for this work.

Copyright

© 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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  1. Linda H Lidborg
  2. Catharine Penelope Cross
  3. Lynda G Boothroyd
(2022)
A meta-analysis of the association between male dimorphism and fitness outcomes in humans
eLife 11:e65031.
https://doi.org/10.7554/eLife.65031

Share this article

https://doi.org/10.7554/eLife.65031

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