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International Journal of Primatology

, Volume 33, Issue 5, pp 1054–1068 | Cite as

Defining Higher Levels in the Multilevel Societies of Geladas (Theropithecus gelada)

  • Noah Snyder-Mackler
  • Jacinta C. Beehner
  • Thore J. Bergman
Article

Abstract

Multilevel societies, identified by two or more nested levels (or modules) of organization, have been touted as some of the most complex social systems. However, few empirical studies have effectively quantified the association patterns that delineate the various levels in such societies. In particular, the multiple levels of gelada society were first described >3 decades ago, yet no operational definitions exist for the higher levels, i.e., levels above the one-male unit. In geladas, multiple units form aggregations that fission and fuse throughout the day, and throughout the year, blurring the distinctions between previously described higher social levels: teams, bands, and communities. Here we use 5 yr of data on the daily composition of a population of geladas living in the Simien Mountains National Park, Ethiopia to test the hypothesis that higher levels of gelada organization are discrete entities. If gelada aggregations are nothing more than a group of units that share a home range, then we expect a continuous distribution of unit association. If, however, gelada aggregations are indeed discrete organizational levels, then we expect discontinuity in the patterns of association. We found significant discontinuity at the 50% association level, indicating a sharp distinction between members of the same band (>50% association) and members of the same community (<50% association). We also found evidence that recently fissioned units form teams that associate significantly more than other band members. Thus, despite their extremely fluid social organization, gelada social levels are nevertheless clearly identifiable and quantifiable. Based on these results, we suggest that gelada society is an extremely flexible, multilevel society with fission–fusion dynamics, and as such gelada society presents an unusual example for understanding the evolution of modular societies.

Keywords

Band Community Modular society One-male unit Social organization Team Theropithecus 

Notes

Acknowledgments

We thank the Ethiopian Wildlife Conservation Authority and the wardens and staff of the Simien Mountains National Park for granting us permission to conduct this research. We thank the guest editors for inviting us to participate in this special issue on multilevel societies. We also thank two anonymous reviewers for their comments on previous versions of this manuscript. We are extremely grateful to H. Gelaye, E. Jajaw, A. Fanta, A. Le Roux, C. Wilton, E. Roberts, D. Pappano, and J. Jarvey for their help with data collection in the field. Funding was provided by the Wildlife Conservation Society (SSF grant 67250), the National Geographic Society (grant 8100–06), the Leakey Foundation, the National Science Foundation (grants BCS-0715179, BCS-0962118, Graduate Research Fellowship Program), the University of Pennsylvania, and the University of Michigan. This research was approved by the University Committee on Use and Care of Animals (UCUCA) at the University of Michigan and adhered to the laws and guidelines of Ethiopia.

References

  1. Abegglen, J. J. (1984). On socialization in hamadryas baboons: A field study. Lewisburg: Bucknell University Press.Google Scholar
  2. Aureli, F., Shaffner, C., Boesch, C., Bearder, S., Call, J., Chapman, C., et al. (2008). Fission-fusion dynamics: New research frameworks. Current Anthropology, 49, 627–654.CrossRefGoogle Scholar
  3. Beehner, J. C., & Bergman, T. J. (2008). Infant mortality following male takeovers in wild geladas. American Journal of Primatology, 70, 1152–1159.PubMedCrossRefGoogle Scholar
  4. Beehner, J. C., Gebre, B., Bergman, T. J., & McCann, C. (2007). Population estimate for geladas (Theropithecus gelada) living in and around the Simien Mountains National Park, Ethiopia. SINET Ethiopian Journal of Science, 30, 149–154.Google Scholar
  5. Bergman, T. J. (2010). Experimental evidence for limited vocal recognition in a wild primate: Implications for the social complexity hypothesis. Proceedings of the Royal Society B: Biological Sciences, 277, 3045–3053.PubMedCrossRefGoogle Scholar
  6. Borgatti, S. P., Everett, M. G., & Freeman, L. C. (2002). UCINET for Windows: Software for social network analysis. Harvard: Analytic Technologies.Google Scholar
  7. Bridge, P. D. (1993). Classification. In J. C. Fry (Ed.), Biological data analysis (pp. 219–242). Oxford: Oxford University Press.Google Scholar
  8. Crook, J. H. (1966). Gelada baboon herd structure and movement: A comparative report. In Symposium Zoological Society of London, pp. 237–258.Google Scholar
  9. Dunbar, R. I. M. (1979). Structure of gelada baboon reproductive units: I. Stability of social relationships. Behaviour, 72–87.Google Scholar
  10. Dunbar, R. I. M. (1983). Structure of gelada baboon reproductive units: II. Social relationships between reproductive females. Animal Behaviour, 31, 556–564.CrossRefGoogle Scholar
  11. Dunbar, R. I. M. (1984). Reproductive decisions: An economic analysis of gelada baboon social strategies. Princeton: Princeton University Press.Google Scholar
  12. Dunbar, R. I. M. (1993). Social organization of the gelada. In N. G. Jablonski (Ed.), Theropithecus: The rise and fall of a genus. Cambridge: Cambridge University Press.Google Scholar
  13. Dunbar R. I. M., Dunbar, E. P. (1975). Social dynamics of gelada baboons. (Contrib Primatol, vol 6) Karger, Basel. pp.1–157.Google Scholar
  14. Fuentes, A. (2011). Social systems and socioecology: Understanding the evolution of primate behavior. In C. Campbell, A. Fuentes, K. Mackinnon, S. Bearder, & R. Sumpf (Eds.), Primates in perspective (2nd ed., pp. 500–511). Oxford: Oxford University Press.Google Scholar
  15. Grueter, C., & Zinner, D. (2004). Nested societies: Convergent adaptations in snub-nosed monkeys and baboons. Primate Report, 70, 1–98.Google Scholar
  16. Kappeler, P. M., & van Schaik, C. P. (2002). Evolution of primate social systems. International Journal of Primatology, 23, 707–740.CrossRefGoogle Scholar
  17. Kawai, M. (1979). Ecological and sociological studies of gelada baboons. Contributions to Primatology, 16.Google Scholar
  18. Kawai, M., Ohsawa, H., Mori, U., & Dunbar, R. I. M. (1983). Social organization of gelada baboons: Social units and definitions. Primates, 24, 13–24.CrossRefGoogle Scholar
  19. Kummer, H. (1968a). Social organization of hamadryas baboons: Field study. Chicago: University of Chicago Press.Google Scholar
  20. Kummer, H. (1968b). Two variations in the social organization of baboons. In P. C. Jay (Ed.), Primates: Studies in adaptation and variability (pp. 293–312). New York: Holt, Rinehart & Winston.Google Scholar
  21. Kummer, H. (1984). From laboratory to desert and back: A social system of hamadryas baboons. Animal Behaviour, 32, 965–971.CrossRefGoogle Scholar
  22. le Roux, A., Beehner, J. C., & Bergman, T. J. (2011). Female philopatry and dominance patterns in wild geladas. American Journal of Primatology, 73, 422–430.PubMedCrossRefGoogle Scholar
  23. Mori, U. (1979). Individual relationships within a unit. In Ecological and sociological studies of gelada baboons (ed. M. Kawai), Karger, Basel. pp. 93–124.Google Scholar
  24. Ohsawa, H. (1979). Herd dynamics. In M. Kawai (Ed.), Ecological and sociological studies of gelada baboons (pp. 47–80). Tokyo: Kondasha & Basel: Karger.Google Scholar
  25. Patzelt, A., Zinner, D., Fickenscher, G., Diedhou, S., Camara, B., Stahl, D., et al. (2011). Group composition of Guinea baboons (Papio papio) at a water place suggests a fluid social organization. International Journal of Primatology, 32, 652–668.PubMedCrossRefGoogle Scholar
  26. Rogers, M. E., Aberneth, K. A., Fontaine, B., Wickings, J., White, L. J. T., & Tutin, C. E. G. (1996). Ten days in the life of a mandrill horde in the Lope Reserve, Gabon. American Journal of Primatology, 40, 217–313.CrossRefGoogle Scholar
  27. Sarkar, D., & Bates, D. (2009). lme4: Linear mixed-effects models using S4 classes. R package version 0.999375–25. Available at: http://CRAN.R-project.org/package=lme4
  28. Schreier, A. L., & Swedell, L. (2009). The fourth level of social structure in a multi-level society: Ecological and social functions of clans in hamadryas baboons. American Journal of Primatology, 71, 948–955.PubMedCrossRefGoogle Scholar
  29. Snyder-Mackler, N., Alberts, S. C., & Bergman, T. J. (2010). Genetics and multi-level societies —Gelada socio-genetic structure. Presented at Animal Behavior Society Conference 2010, Williamsburg, VA.Google Scholar
  30. Sokal, R. R., & Rohlf, F. J. (1962). The comparison of dendrograms by objective methods. Taxon, 11, 33–40.CrossRefGoogle Scholar
  31. Swedell, L. (2002). Affiliation among females in wild hamadryas baboons (Papio hamadryas hamadryas). International Journal of Primatology, 23, 1205–1226.CrossRefGoogle Scholar
  32. Swedell, L. (2006). Strategies of sex and survival hamadryas baboons: Through a female lens. Upper Saddle River: Prentice Hall.Google Scholar
  33. Swedell, L., & Schreier, A. (2009). Male aggression toward females in hamadryas baboons: Conditioning, coercion, and control. In M. Muller & R. W. Wrangham (Eds.), Sexual coercion in primates and humans: An evolutionary perspective on male aggression against females (pp. 244–268). Boston: Harvard University Press.Google Scholar
  34. Swedell, L., Saunders, J., Schreier, A., Davis, B., Tesfaye, T., & Pines, M. (2011). Female “dispersal” in hamadryas baboons: Transfer among social units in a multilevel society. American Journal of Physical Anthropology, 145(3), 360–370.PubMedCrossRefGoogle Scholar
  35. Whitehead, H. (2009). SOCPROG programs: Analysing animal social structures. Behavioral Ecology and Sociobiology, 63, 765–778.CrossRefGoogle Scholar
  36. Wittemyer, G., Douglas-Hamilton, I., & Getz, W. M. (2005). The socioecology of elephants: Analysis of the processes creating multitiered social structures. Animal Behaviour, 69, 1357–1371.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Noah Snyder-Mackler
    • 1
  • Jacinta C. Beehner
    • 2
  • Thore J. Bergman
    • 3
  1. 1.Department of PsychologyUniversity of PennsylvaniaPhiladelphiaUSA
  2. 2.Departments of Anthropology and PsychologyUniversity of MichiganAnn ArborUSA
  3. 3.Departments of Psychology and Ecology & Evolutionary BiologyUniversity of MichiganAnn ArborUSA

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