Human Nature

, Volume 21, Issue 3, pp 330–354 | Cite as

Interpersonal Aggression among Aka Hunter-Gatherers of the Central African Republic

Assessing the Effects of Sex, Strength, and Anger
  • Nicole Hess
  • Courtney Helfrecht
  • Edward Hagen
  • Aaron Sell
  • Barry Hewlett


Sex differences in physical and indirect aggression have been found in many societies but, to our knowledge, have not been studied in a population of hunter-gatherers. Among Aka foragers of the Central African Republic we tested whether males physically aggressed more than females, and whether females indirectly aggressed more than males, as has been seen in other societies. We also tested predictions of an evolutionary theory of physical strength, anger, and physical aggression. We found a large male bias in physical aggression. Controlling for anger, we found an adult female bias in indirect aggression. Physical strength predicted anger, which predicted hitting, although results were sensitive to the inclusion or exclusion of traditional healers, who were physically and emotionally distinct from other Aka. With some important caveats, our results generally support the predicted sex differences in physical aggression and indirect aggression, and the predicted relationships among anger, strength, and aggression.


Physical aggression Indirect aggression Social norms Sex differences Foragers 



Funding provided by the College of Liberal Arts, Washington State University. We thank our Ngandu research assistants and the Aka participants.


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Copyright information

© Springer Science + Business Media, LLC 2010

Authors and Affiliations

  • Nicole Hess
    • 1
  • Courtney Helfrecht
    • 2
  • Edward Hagen
    • 1
  • Aaron Sell
    • 3
  • Barry Hewlett
    • 1
  1. 1.Department of AnthropologyWashington State UniversityVancouverUSA
  2. 2.Department of AnthropologyWashington State UniversityPullmanUSA
  3. 3.Department of PsychologyUniversity of CaliforniaSanta BarbaraUSA

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