Understanding the origins of animal social life and its impact on health outcomes presents a major challenge for researchers. This is because social diversity is influenced by multiple evolutionary and ecological factors and has complex impacts on health. My research addresses this challenge by examining the influence of both intrinsic characteristics (e.g. phylogenetic history) and extrinsic socioecological factors (e.g. resource competition, human impact) on animal social life and health. Its broader impact lies in the conservation and management of both problematic and endangered wildlife populations. To-date, my work has focused on captive and free-living groups of nonhuman primates, particularly macaques (Macaca sp.). In addition to displaying diverse social structures, macaques also share close physiology, evolutionary histories, and ecological space with humans, making them an ideal model genus. First I present aspects of my past research, which focused on understanding the evolutionary origins of macaque social structure. Specifically, I found that some aspects of macaque social structure related to their dominance hierarchies show strong phylogenetic signals, while others related to the structure of affiliative grooming social networks, show only
moderate-to-weak signals. Further, my findings on free-ranging rhesus macaques (M. mulatta) and wild Tibetan macaques (M. thibetana) found that socioecological factors may influence variation in grooming exchange behaviors. My current research deals with how macaque social structure influences health outcomes, specifically infectious disease risk. I examine how broader social contexts and/or microbe-specific characteristics may determine whether/when macaques’ social networks may socially buffer animals against pathogenic infection, facilitate contact-mediated pathogen transmission, or present ‘social-bottlenecks’ that prevent the group-wide spread of infectious agents. I’m also currently conducting long-term assessments of human-macaque interfaces as dynamic, Coupled-Systems. This work is examining how anthropogenic factors may influence the social structure of free-living macaque populations in Asia by inducing environmental stressors or by constraining the time available for animals to engage in social interactions.
As part of my three-track future research plan, I will first build on my research on captive macaques to unravel the co-evolutionary, paradoxical links between primate socioecology and disease risk. I also aim to capitalize on the on-going coupled systems research to test conflicting hypotheses (evolutionary versus acquired) related to the sharing of gut microbiota at human-macaque interfaces. Finally, I look forward to establishing the Coupled-Systems approach as a unifying framework to assess the drivers and feedback effects of interactions and conflict between humans and other wildlife groups and populations. I end by encouraging the conceptualization of social structure as a set of social reaction-norms, i.e. where groups/species may respond similarly to variation in ecological factors, but have inherently different ranges of responses to the same conditions.