Behavioral Ecology and Sociobiology

, Volume 64, Issue 6, pp 1001–1009 | Cite as

Digit ratio (2D:4D) and dominance rank in female rhesus macaques (Macaca mulatta)

  • Emma Nelson
  • Christy L. Hoffman
  • Melissa S. Gerald
  • Susanne Shultz
Original Paper


Female rhesus macaques exhibit matrilineal dominance structures, and high dominance rank confers fitness benefits across a lifetime and across generations. Rank effects are “inherited” through social processes that are well understood; however, biological mechanisms that might impact these processes are not well known. Recently, it has been shown that prenatal androgens appear to be implicated in supporting dominance rank hierarchies in some mammals. In humans, interindividual differences in the second (index) to fourth (ring) digit ratio (2D:4D) have been linked indirectly to variation in prenatal androgens, with low 2D:4D in both sexes associated with higher inferred prenatal androgen effects. 2D:4D has also been related to dominant social behavior and has been shown to co-vary with social systems across nonhuman primate species. Here, we investigate how 2D:4D co-varies with socially inherited dominance rank in female rhesus macaques. Low 2D:4D was associated with higher-ranking females, while higher 2D:4D was associated with lower-ranking females. Similar relationships were also shown between ranked families within matrilines. This is the first study to show such a relationship between 2D:4D and dominance rank in a nonhuman primate and suggests that prenatal androgen effects could be involved in the maintenance of dominance rank in female cercopithecine primates.


Primates Prenatal androgens Prenatal programming Competition Aggression Dominance rank 



We would like to thank all the staff at the Caribbean Primate Research Center, Cayo Santiago for their support and help. We also thank Dario Maestripieri and Anja Widdig for kindly allowing access to their subjects to collect data and Doreen Hess, Constance Dubuc, and Julie Cascio for help with data collection. We would also like to thank Martin Voracek, Kobe Millet, and three anonymous reviewers who helped improve the manuscript. The protocol for this study was approved by the Institutional Animal Care and Use Committee, Medical Sciences Department, University of Puerto Rico. This publication was made possible by Grant Number P40RR003640 from the National Center for Research Resources (NCRR), a component of the National Institutes of Health (NIH). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of NCRR or NIH. Funding support was provided by the University of Liverpool, the British Academy Centenary Project, and the British Association of Biological Anthropology and Osteoarchaeology.


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Emma Nelson
    • 1
  • Christy L. Hoffman
    • 2
  • Melissa S. Gerald
    • 3
    • 4
  • Susanne Shultz
    • 5
  1. 1.School of Archaeology, Classics and EgyptologyUniversity of LiverpoolLiverpoolUK
  2. 2.Department of Comparative Human DevelopmentUniversity of ChicagoChicagoUSA
  3. 3.Department of Medicine, Medical Sciences CampusUniversity of Puerto RicoSan JuanUSA
  4. 4.Laboratory for Primate Morphology and GeneticsUniversity of Puerto Rico Medical SchoolSan JuanUSA
  5. 5.Institute of Cognitive and Evolutionary AnthropologyUniversity of OxfordOxfordUK

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