| Understanding the evolution of sociality and social systems has been a major endeavor among evolutionary anthropologists and animal behaviorists. During the last two decades in particular, behavioral ecologists have found it a major challenge to explain broad inter- and intraspecific variation in primate social systems and in particular, variation in aspects of social structure related to dominance relationships, conflict management, and cooperative exchanges. One reason has been the lack of general consensus regarding the reliability of one or more operational behavioral measures related to dominance asymmetry and social power, despite these traits being central or core aspects of social structure. Although operational measures of both dominance asymmetry (Directional Consistency Indices, or DCI, and levels of counter-aggression) and social power (hierarchical steepness) are currently available, it is unclear whether one or more measures are (1) consistent with each other, and/or (2) are more suitable for groups with certain sets of characteristics. Another reason has been the proposal of apparently conflicting models to explain this variation in social structure. For instance, models based on phylogenetic constraints posit that several aspects of social structure are highly integrated, inherent species-specific characteristics that co-vary with each other and with species' evolutionary relationships. In contrast, models based on current socioecological factors (the Ecological Model of Female Social Relationships, or the EMFSR) posit that social structure varies widely between species with current ecological conditions, and possibly across and within groups of the same species of varying sizes.;My dissertation research addresses both the methodological issue and the two models described above, focusing on the primate genus Macaca. All macaques show broadly similar patterns of social organization (e.g. female philopatry, male dispersal, and linear dominance hierarchies) and yet, broad inter- and intraspecific variation in several aspects of social structure, particularly in the extent to which dominance relationships are re-enforced. They are therefore uniquely appropriate for pursuing the overall aim of my thesis, i.e. to examine variation in dominance asymmetry and social power in macaques as a means to gain a greater insight into the roles of internal (phylogenetic) constraints and/or external (socioecological) factors in shaping variation in primate social structure. (Abstract shortened by UMI.) . |
