Abstract
Bonobos have a reputation as a female-dominated and egalitarian species. We examined the 2 aspects of dominance in 6 captive bonobo groups. Females do not consistently evoke submission from all males in all contexts. Though females occupy the highest-ranking positions in the dominance hierarchy, there are in each group males that obtain rather high ranks and are able to dominate ≥1 female. Thus female dominance is not complete and hierarchies can be better described as nonexclusive female dominance. We studied egalitarianism by measuring linearity and steepness of dominance hierarchies. The hierarchies of all groups are highly linear. Hierarchies among males are steeper than among females. On average, male bonobos are more despotic than females, but females too can have despotic relations, both with other females and with males. Hence one can call bonobos in captivity semidespotic rather than egalitarian.
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Acknowledgments
We thank the directory, curators, and keepers of the institutions where we observed bonobos for their kind cooperation. We are thank all colleagues from the Centre for Research and Conservation who commented on the manuscript. J. M. G. Stevens received a grant from the Institution for the Promotion of Innovation by Science and Technology (IWT: grant 3340). A postdoctoral research grant of the National Fund for Scientific Research (FWO supported H. Vervaecke. We thank the Flemish government for structural support of the CRC of the RZSA. We thank 2 anonymous reviewers for their very constructive comments on an earlier version of the manuscript.
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Stevens, J.M.G., Vervaecke, H., de Vries, H. et al. Sex Differences in the Steepness of Dominance Hierarchies in Captive Bonobo Groups. Int J Primatol 28, 1417–1430 (2007). https://doi.org/10.1007/s10764-007-9186-9
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DOI: https://doi.org/10.1007/s10764-007-9186-9