Luis A. Ebensperger, P. Universidad Católica de Chile, Chile Luis Ebensperger has developed a research career to examine causes (ecological, evolutionary) and consequences of rodent social living. He has successfullycombined field observational, demographical, and lab approaches to address why animals congregate, how they cooperate, and what are the fitness effectsof group-living and cooperation. His recent work has addressed the neuroendocrine and immune responses of social mammals and the links between these mechanisms and direct fitness. He has been able to acquire evidence not only from several caviomorph rodent models, but also from other animal models, including ungulates. In addition to publishing research papers in high impact journals, he has produced papers aimed to summarize andprovide an integrative view to current social behavior theory. Loren D. Hayes, Department of Biological and Environmental Sciences, University of Tennessee at Chattanooga, USA Loren Hayes' research program examines the ecological and neural drivers of social systems, costs and benefits of communal care, and fitness consequences of group-living. Hayes has successfully combined field and laboratory work to determine the mechanisms of maternal investment and neuroendocrine sources of direct fitness variation in social voles and degus, respectively. His NSF-funded program includes collaborations in Chile, the U.S., and Taiwan and has generated 30 peer-reviewed papers, including two synthetic reviews on an integrated theory for sociality. Additionally, he co-organized a workshop on vertebrate sociality in Chile, participated in a National Evolutionary Synthesis Center working group on integrative animal sociality, and co-coordinated a Journal of Mammalogy Special Feature on caviomorph social systems.