Research

Our research focuses on how the phenotype – particularly behavior – of non-human animals and humans influences their social and physical environment, and the consequences of these influences on the development and evolution of behavior.  We ask how individuals impact their social and physical environment through 1) the direct and indirect effects of their phenotypes on the behavior and dynamics of group-mates, competitors, mates and antagonists like predators and pathogens, and 2) their decisions to move to new groups or locations.  We are interested in how these effects interact with patterns of social organization, habitat use, within-group cooperation and conflict, information use, and disease dynamics, and, ultimately, how these feed back to influence development and selection.

Ongoing projects include

Network Dynamics and Conflict Management in a Cichlid Fish

Human and non-human animals live in “social networks” of interactions and relationships. How do these social networks change after conflict over things such as opportunities to reproduce or opportunities to gain social status? Do networks change in ways that make conflict worse in the future, or do they change in ways that prevent conflict from re-emerging? We are exploring how social networks form and change after conflict in the cichlid fish Neolamprologus pulcher. These fish are “cooperative breeders” that live in relatively stable, long-lasting groups. Some individuals – usually social subordinates – experience little direct reproduction and care for the offspring of other group members. Our work on social networks in this species includes:

a) Exploring the influences of third parties on social interactions.
b) Exploring the influences of neighboring groups on within-group interactions.
c) Exploring the responses of social networks to perturbations, such as exposure to neighbors or removal of group members.

Social Status, Personality, and Information Use in Cichlid Fishes

Animals may benefit from using information gained from others. However, the salience of information from others may vary depending on individual state. Further, if attention is limited, individuals may not pay attention to all individuals in a social group equally. Differences other than social status may also influence information use. Individuals differing in ‘personality’ may acquire or use social information differently. We are exploring how social status and personality of demonstrators and observers influences attention and transmission of information in groups of two highly social African cichlid fish, N. pulcher and Julidochromis ornatus.

Management of Open Access

  • In collaboration with Mark Moritz (Anthropology), we are examining how mobile pastoralists in the Logone floodplain in the Far North of Cameroon coordinate their movements to avoid conflict and overgrazing in a land tenure system that is commonly described as open access, a situation generally regarded as leading to a tragedy of the commons. The hypothesis is that this management system is best understood as a case of complex adaptive system, in which individual decision-making, coordination of movements among pastoralists, and participation in an information sharing network result in the emergence of a system in which access to and use of grazing resources is managed. We have evaluated this hypothesis in an interdisciplinary study of pastoral mobility that integrates spatial and ethnographic analyses as well as multi-agent simulations.

    • Modeling Regime Shifts in the Logone Floodplain

  • African floodplains are an excellent example of coupled human-natural systems because they exhibit strong interactions among multiple social, ecological, and hydrological systems. The intra-annual and inter-annual variations in the area, depth, and duration of seasonal flooding have direct and indirect impacts on ecosystems and human lives and livelihoods. We are develop a set of integrated models that simulates the social, ecological and hydrological systems, and the dynamic couplings among these, of the Logone floodplain in Cameroon. The model will allow us to simulate the impacts of climate change scenarios and human modifications of the landscape on the social, ecological, and hydrological systems. Fishermen in the Logone floodplain have been modifying the floodplain’s hydrology by constructing thousands of individually owned fish canals. The cumulative effect of these canals may equal the impact of large-scale dams.