Group phenotypic composition shapes emergent network structures and selection regimes in Bolitotherus cornutus

A social network is the set of interactions or associations between all individuals in a population. The position an individual holds within its network modulates exposure to grooming, social information, parasites, and disease. Group social structures themselves are also thought to be adaptive. But we understand little about the causes of variation between groups, both in overall network structures and in the evolutionary pressures acting on network position. My dissertation work explored how the composition of groups impacts both network structure and selection on network position, using two experimental manipulations of mesocosm populations of the forked fungus beetle (Bolitotherus cornutus). My first set of results suggest that sociability is a personality trait, and show that the composition of social personalities within a population dramatically alters overall network structure. The results of my second experiment show that age creates variation in social behavior within individuals over time, among individuals, and among groups. Additionally, the age structure of populations contributes to variation in the selection regimes acting on network traits. Taken together, these findings contribute to our understanding of the basis of individual and group differences in social traits, as well as the relationship between them.