Life history and social factors influencing social network structure in Octodon degus

Presenter(s)

Logan Platt

Abstract or Description

Animal social systems consist of four interrelated components: social organization, social structure, mating system, and parental care. Social structure influences the fitness of individuals, and this is evident in many species. Social structure may change due to different motivations, like mating behaviors or behaviors that contribute to parental care of offspring. I hypothesize that sexual preference influences social structure based on the life history stage of the species. During mating season, the interactions of an individual will likely be motivated by mating behaviors. During rearing season, motivation may shift to parental care behaviors. I also hypothesize that group membership and composition (social organization) influence social structure. Social interactions are expected between individuals that are familiar and/or that are closely related. In groups with non-kin, familiarity of individuals and selection for direct benefits of cooperation may facilitate affiliative interactions. In some mammals, group formation is associated with morphotypes, like the degree to which individuals were masculinized during development. The link between morphotype and social structure has not yet been described. The objective of my study is to investigate the influences of homophily according to morphotype, social organization, and life history stages on social network structure in degus (Octodon degus). The degu is a communally-breeding rodent endemic to central Chile. I will accomplish this by utilizing social network analysis. Network analyses involve creating networks using interaction data between individuals to infer weighted associations. Network metrics can be calculated and utilized in analyses to find connections between social network structure (SNS) and individual. The results of these analyses will be forthcoming soon. This project is significant because it will be one of the first to analyze connections between individual morphotype and social network structure. Funded by NSF OISE 1854177.

Mentor

Loren Hayes