My work focuses on the role of plant pathogens in (A) controlling or facilitating biological invasions by plants, (B) structuring plant communities, and (C) modulating the effects of global change on terrestrial ecosystems. My group works on viruses, bacteria, and fungi that infect wild plants, chiefly grasses and other herbaceous species. Ultimately, I am interested in the implications of these processes for the sustainable provisioning of ecosystem services and for the conservation of biological diversity.
My research focuses on plant community ecology and such related fields as plant geography, conservation biology, ecoinformatics and plant population ecology. I am particularly interested in how plant communities are assembled and vary across landscapes. Toward this end I am helping define the emerging discipline of ecoinformatics through development of international databases and standards for large-scale data integration and exchange. My current research on the vegetation of the Southeastern United States includes on-going studies of the long-term dynamics of Southeastern forests, human impacts on floodplain ecosystems, targets for restoration, and more generally factors influencing the composition and species diversity of terrestrial plant communities across a range of spatial scales.
The primary research projects in my lab span topics from evolutionary genetics to behavioral ecology. Prior, current and future projects of mine focus on theoretical studies of speciation and reinforcement but include work on mate choice, learning and imprinting, aposematic coloration, and brood parasitism. My main goal is to use mathematical models to integrate rigorous evolutionary theory with hypotheses explaining behavioral and ecological patterns and phenomena.
I study the ultimate and proximate factors controlling flexibility in reproductive behavior. Using songbirds as a system, I use field and laboratory studies to investigate the ecological cues regulating reproductive flexibility, the neural integration of these cues, and the neural mechanisms precipitating adaptive behavioral outcomes. Of particular interest is the study of courtship and mate-choice behavior and how the songbird brain integrates ecological and social information. I am also interested in how the timing of reproduction, reproductive effort, and family planning are controlled. I use high performance liquid chromatography for the measurement of central catecholamines and immunocytochemistry and microscopy for quantifying neuropeptides and the expression of immediate early genes as markers of neural activity.
My research interests are wide ranging, including topics in conservation biology and plant ecology. I have had several foci: species richness (including the All Taxa Biodiversity Inventory in Great Smoky Mountains National Park, beta diversity (including the comparison of diversity in different parts of the world that have similar climates and the connections to coinservation planning),and the ecology of natural disturbances (including connections to environmental ethics and conservation of biodiversity). Through my role as Director of the University's North Carolina Botanical Garden, a conservation focused garden, I am also involved in research and poliy in invasive species biology, ecological restoration, ex situ conservation and reintroduction of rare species, and related subjects.
My lab concentrates on studying the molecular genetic basis of the evolutionary processes of adaptation and speciation. The questions we ask are what are the sequence changes that lead to variation between species and diversity within species, and what can these changes tell us about the processes that lead to their evolution. We use a number of different techniques to answer these questions, including molecular biology, sequence analyses (i.e. population genetics and molecular evolution techniques), physiological studies, and examinations of whole-organism fitness. Currently work in the lab has focused on a intertidal copepod species that is an excellent model for the initial stages of speciation (and also provides opportunities to study how populations of this species adapt to their physical environment).
