Research‎ > ‎

Social Networks

Network approach to understanding social hierarchies
Social network theory provides a framework for quantitative analyses of social interactions. I am currently working with David McDonald at the University of Wyoming to apply network theory to a variety of problems in evolution, including the analysis of social dominance structures. We are using tools developed in other fields (systems biology, community ecology, sociology) to understand emergent patterns of animal groups. 

Social network structure of wintering migrant birds and the evolution of social signals

I am also working on a collaborative project with Bruce Lyon and Alexis Chaine, integrating signalling strategies and overall wintering strategies of a migrant, the golden-crowned sparrow (Zonotrichia atricapilla). We consider plumage signalling, winter singing, flocking and space use as components of an overall social strategy through which individuals seek to maximize their survival and condition during the non-breeding season (i.e., more than half of their lifetime). This research, conducted on the UCSC campus, has also been a major source of undergraduate mentorship. 

Thus far, we have found that sparrow flocks are formed from relatively cohesive clusters of birds that share overlapping home ranges and flock together often. Surprisingly, the spatial patterns of these "social communities" are very consistent across years, and this is in part driven by the fact that birds returning to the study site across years flock together with birds they flocked with last year--a level of across-year social stability that we had not suspected (Shizuka et al. 2014). This could affect the evolution of social signals--while conventional signals like badges of status might mediate contests between strangers (Chaine et al. 2011; Chaine et al. 2013), stable social partners may interact differently. We are currently working on connecting the dots between how ecological factors (resource distribution, demography) affect social structure, and how social structure affects the evolution of social competition.