Article

Frequency-dependent female genital cutting behaviour confers evolutionary fitness benefits

  • Nature Ecology & Evolution 1, Article number: 0049 (2017)
  • doi:10.1038/s41559-016-0049
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Abstract

Female genital cutting (FGC) has immediate and long-term negative health consequences that are well-documented, and its elimination is a priority for policymakers. The persistence of this widespread practice also presents a puzzle for evolutionary anthropologists due to its potentially detrimental impact on survival and reproductive fitness. Using multilevel modelling on demographic health survey datasets from five West African countries, here we show that FGC behaviour is frequency-dependent; the probability that girls are cut varies in proportion to the FGC frequency found in their ethnic group. We also show that this frequency-dependent behaviour is adaptive in evolutionary fitness terms; in ethnic groups with high FGC frequency, women with FGC have significantly more surviving offspring than their uncut peers, and the reverse is found in ethnic groups with low FGC frequency. Our results demonstrate how evolutionary and cultural forces can drive the persistence of harmful behaviours.

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Acknowledgements

We would like to thank F. Jordan, D. Lawson, A. Samarasinghe and C. Uggla for their helpful comments on previous drafts, and R. Parker for MLwiN guidance.

Author information

Affiliations

  1. Department of Archaeology and Anthropology, University of Bristol, 43 Woodland Road, Bristol BS8 1UU, UK

    • Janet A. Howard
    •  & Mhairi A. Gibson

Authors

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Contributions

J.A.H. and M.A.G. conceived and designed the study, J.A.H. performed data analysis, and J.A.H. and M.A.G. wrote the paper.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Janet A. Howard.

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    Supplementary Information

    Supplementary Tables 1–6; Supplementary Figure 1