Abstract # 222:

Scheduled for Monday, September 21, 2009 02:00 PM-02:10 PM: Session 24 (Shell Room) Oral Presentation


F. White and M. Waller
University of Oregon, Department of Anthopology, Eugene, Oregon 97403-1218, USA

Bonobo female sociality may have evolved as cooperative defense of food or as defense against male aggression. Lack of lethal raiding in bonobos may also be a consequence of bonobo female alliances compared to chimpanzees. We evaluated if female affiliative alliances mitigate male aggression in Lomako bonobos from 466 hours of focal animal follows of 205 parties. Bonobo female alliances did not prevent male aggression. Male aggression rate against females increased with number of females present [r=0.90, p<0.01]. The rate of aggression among males was highest when more females were present but was not significant [r=0.41, n.s.]. Female alliances were important in the relative power of males and females. At Lomako, male bonobos were socially dominant to females in dyadic interactions but female coalitions facilitate greater female power in feeding priority and control of prized resources including meat. Male-male aggression among Lomako bonobos often occurred away from females and involved significantly more disputes over the control of access into feeding trees than other circumstances [G=18.69, p<0.001]. Male-male aggression resulted in a dominant male controlling access to a feeding tree. This was when significantly more matings occur [G=124.71, p<0.001]. Male-male aggression in chimpanzee lethal raids mostly occurs away from females as does within community male-male bonobo aggression. We expect bonobo female alliances to have little impact on the potential for intercommunity male-male aggression.