Human Nature

, Volume 21, Issue 1, pp 1–18 | Cite as

The Social Strategy Game

Resource Competition within Female Social Networks among Small-scale Forager-Horticulturalists
  • Stacey L. RucasEmail author
  • Michael Gurven
  • Hillard Kaplan
  • Jeffrey Winking


This paper examines social determinants of resource competition among Tsimane Amerindian women of Bolivia. We introduce a semi-anonymous experiment (the Social Strategy Game) designed to simulate resource competition among women. Information concerning dyadic social relationships and demographic data were collected to identify variables influencing resource competition intensity, as measured by the number of beads one woman took from another. Relationship variables are used to test how the affiliative or competitive aspects of dyads affect the extent of prosociality in the game. Using a mixed-modeling procedure, we find that women compete with those with whom they are quarreling over accusations of meat theft, mate competition, and rumor spreading. They also compete with members of their social network and with those who were designated as cooperative helpers or as close kin. Women take fewer beads from desired friends, neighbors, and from those viewed as enemies. We interpret favoritism toward enemies as resulting from fear of retribution. Our results suggest that social relations among women are multifaceted and often cannot be simplified by exclusive focus on genetic relatedness, physical proximity, or reciprocity. We argue that a complex understanding of cooperation and competition among women may require important contextual information concerning relationship history in addition to typical features of resource ecology.


Experimental economics Social networks Resource competition Altruism Tsimane 



We would like to thank the Tsimane women of our host communities for their gracious participation and wonderful camaraderie. This research was funded by LAII Field Research Grants, provided by the Tinker Foundation, and by NSF grant BCS-013274. We would also like to thank Dan Fessler, Steve Gangestad, and our anonymous reviewers for their helpful criticisms.


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Copyright information

© Springer Science + Business Media, LLC 2010

Authors and Affiliations

  • Stacey L. Rucas
    • 1
    Email author
  • Michael Gurven
    • 2
  • Hillard Kaplan
    • 3
  • Jeffrey Winking
    • 4
  1. 1.Department of Social SciencesCalifornia Polytechnic State University (Cal Poly)San Luis ObispoUSA
  2. 2.Department of AnthropologyUniversity of California Santa BarbaraSanta BarbaraUSA
  3. 3.Department of AnthropologyUniversity of New MexicoAlbuquerqueUSA
  4. 4.Department of AnthropologyTexas A&M UniversityCollege StationUSA

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