Abstract # 199:

Scheduled for Monday, September 15, 2014 02:00 PM-02:15 PM: Session 27 (Mary Gay) Oral Presentation


W. Eckardt1,2, K. Fawcett1 and A. W. Fletcher2
1Dian Fossey Gorilla Fund International, 800 Cherokee Ave, Atlanta, Georgia 30315, USA, 2Department of Biological Science, University of Chester, UK
     Resolution models of parent-offspring conflicts incorporate assumptions about phenotypic interactions between parents and offspring. One key question addressed by resolution models relates to who wins the conflict, parent, offspring, or both. We aimed to identify mother-offspring behavioral conflicts (BC) in Virunga mountain gorillas and investigated how and to what extent mother and offspring shape maternal investment patterns. We collected maternal rejection behavior and offspring whimper signals, which are common indicators of BCs, during focal sampling on 37 mother-offspring dyads monitored by the Karisoke Research Center resulting in >1,150 observation hours. Findings suggest that mountain gorilla mother-offspring dyads engage in various BCs over the timing and the quantity of maternal investment, e.g. suckling. The impact of mother and offspring on the mediation of BCs depended on the conflict context and offspring age, with short-term effects of maternal rejection on offspring behavior often being different from long-term effects. Long-term effects of BC suggest that mothers succeeded in achieving their aims, although offspring managed to impede and slow down the reduction in maternal investment. Thus, our findings provide some support that pro-rata models, with conflict resolutions at a compromise level between the optima of both parties, apply to BC mediation in mountain gorillas rather than supporting the alternative hypothesis that BC outcomes are always on mother’s optimum through force majeure.