Over the years, we have worked on a number of topics—ranging from migratory connectivity to foraging behavior to systematics—using an assortment of integrative tools and techniques. Currently, we are primarily focused upon two major research themes that integrate animal behavior, molecular genetics, neuroendocrinology, and evolutionary ecology across different levels of analysis and scales of biological organization: 

SOCIAL EVOLUTION: understanding the causes and consequences of sociality, as well as the evolutionary transitions in social evolution 

ENVIRONMENTAL COPING: determining the behavioral, physiological, & molecular adaptations used to cope with environmental change

We use a variety of genomic and physiological tools to ask evolutionary and ecological questions that span levels from molecules to populations. We do extensive field work around the world using both long-term studies of marked social groups, as well as short-term sampling of populations along environmental gradients. To generate and test novel hypotheses, we also use mathematical modeling and phylogenetic comparative methods with large trait and biogeographic databases. Our study systems, which span invertebrates to vertebrates, are chosen for the specific questions that we ask. Although open to other systems, questions, and methods, most lab members employ an integrative approach to ask related questions in our primary study systems. However, in addition to working on topics related to the major research themes of the lab, previous lab members have also worked on projects in disease ecology, life history evolution, and more. Below are the animal models with which we work (and have worked with in the past) and the research areas thats we are currently studying.

SOCIAL EVOLUTION

Environmental Uncertainty and Animal Societies:  Our work in cooperatively breeding starlings and weavers examines how variable and unpredictable climates influence social evolution. Using game theory, comparative analyses, and empirical tests, we are exploring how cooperative breeding behavior may be a bet-hedging strategy to reduce environmentally-induced fecundity variance. Additionally, we explore how annual variation in rainfall influences group size and stability, as well as numerous life history and physiological traits.

Sexual Selection and Social Competition:  We are studying inter and intra-sexual competition and social signaling (song, plumage) in starlings and hummingbirds. Using theoretical models and empirical tests, we are also exploring the interactions between dominance rank, social structure, and stress physiology in starlings and weavers. Finally, we are studying female-female competition in pebble-mound mice and how environmental variation shapes not only social behavior, but infraspecific competition and trait evolution in females.

Evolution of Social Diversity:  We are examining the evolution of social diversity in Synalpheus shrimps—which range in social complexity from pairs, to colonies of pairs, to eusocial societies—by quantifying life history variation and exploring the key evolutionary transition, the differentiation of castes, suggested to uniquely define eusocial species.

Genome Architecture of Social Phenotypes:  We are studying the mechanistic basis of caste differentiation and social phenotypes in eusocial snapping shrimp and cooperative burying beetles by examining role- and population-specific patterns of gene expression and patterns of genetic variation. In addition to exploring the genetic drivers of sociality in shrimp, we are also examining how social living influences the evolution of genome architecture by studying genome size evolution and transposable element accumulation. 

Social Network Structure in Fluctuating Environments:  Grey-capped social weavers have a complex, multi-layer cooperatively breeding society whose dynamics fluctuate annually. We are exploring how the social dynamics (cooperation and conflict) and stability of complex weaver societies are influenced by annual variation in precipitation, and how social network dynamics relate to stress physiology.

ENVIRONMENTAL COPING

Adaptation Along Environmental Gradients:  We are examining stress physiology, immune function, and patterns of genetic and epigenetic variation in different populations of starlings along temperature and precipitation gradients in the tropics. Additionally, we are exploring color evolution along this rainfall gradient, including not just spectral colors, but also gene expression differences in developing feathers.

A Framework for Environmental Coping:  We are developing a theoretical framework that predicts evolutionary responses to environmentally-driven fluctuating selection, and using it to explore the evolution of physiological coping mechanisms, as well as their genetic and epigenetic architectures.

Epigenetics, Plasticity and Environmental Variation:  We are examining how developmental conditions (both social and environmental) influence social phenotypes, stress physiology, and fitness later in life, and we are exploring DNA methylation as one potential mechanism underlying this relationship in starlings. Although we emphasize the stress access, we also look globally at patterns of DNA methylation across the genome.

Cooperation and Ecological Dominance:  We are exploring how cooperative breeding behavior in burying beetles and eusociality in snapping shrimps influences competitive ability against conspecifics, niche breadth and range expansion, ecological generalism vs. specialism, and ecological dominance.