, Volume 33, Issue 1, pp 69–83 | Cite as

A model of the gelada socio-ecological system

  • R. I. M. Dunbar


Data from three populations of gelada baboons are used to generate a model of the species' socio-ecology that relates time budget requirements to group size, day journey length, and relevant environmental parameters. The model is used to examine the range of environmental conditions under which gelada could survive. This analysis indicates that a grazing primate like the gelada would run out of available time for foraging at just above and just below the altitudes at which they are now found. This suggests that, contrary to previous supposition, gelada were not driven into a retreat habitat by more competitivePapio baboons, but rather withdrew from lower altitude habitats because they could not survive under these conditions as the climate deteriorated during the Holocene.

Key Words

Gelada Time budgets Group size Socioecology Model 


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Copyright information

© Japan Monkey Centre 1992

Authors and Affiliations

  • R. I. M. Dunbar
    • 1
  1. 1.Department of AnthropologyUniversity College LondonLondonEngland

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