Encyclopedia of Evolutionary Psychological Science

Living Edition
| Editors: Todd K. Shackelford, Viviana A. Weekes-Shackelford

Sex Ratio

  • David P. SchmittEmail author
Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-16999-6_36-1



Sex ratio is the relative number of men to women in a given population


The ratio of men to women within a mating population varies significantly across time and culture. Evolutionary psychologists expect, and find, that variations in human sex ratios are predictably associated with differences in human mating strategies, such as changes in sociosexual attitudes, intensity of mate competition (e.g., intrasexual violence), and patterns of courtship and mate choice.

Mating Strategies

Every primate species seems to have a “natural” mating strategy. Some primates are monogamous (e.g., gibbons), some polygynous (e.g., gorillas), and some engage in multimale-multifemale mating as their primary means of reproduction (e.g., chimpanzees; Dixson 1998). The human primate, however, appears to have a diverse and varied menu of reproductive strategies, with different people deploying different strategies as individuals, and within their own...

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© Springer Nature Switzerland AG 2018

Authors and Affiliations

  1. 1.Brunel University LondonUxbridgeUK

Section editors and affiliations

  • Gayle Brewer
    • 1
  1. 1.University of LiverpoolLiverpoolUK