Research Interests

My core personal research focuses on theoretical and conceptual issues at the population and community levels of ecological organization, and on the task of linking ecology with evolutionary biology. In addition to basic research, I am interested in bringing modern ecological theory to bear on significant applied problems, particularly in conservation biology. I have also carried out large-scale experiments on habitat fragmentation. My students include both theoreticians and empirical, experimental ecologists. I have historically collaborated with many faculty at a wide range of institutions, both inside and outside the USA. Some specific examples are as follows:

Multispecies interactions in food webs. My current work in the area focuses on three broad issues: (1) examining "community modules" (3-6 species interacting in defined configurations) that have been historically neglected, (2) exploring implications of spatial dynamics and temporal heterogeneity for food web structure, and (3) developing food web models tailored to specific ecosystems. As an example of (1), in the context of a working group on "Conservation and Infectious Disease" at NCEAS (National Center for Ecological Analysis and Synthesis, Santa Barbara, CA), I have been developing models which combine host-pathogen and predator-prey interactions. These models suggest that generalist predators can indirectly benefit prey populations, via a reduced load in infectious diseases. As an example of (2), I am studying how landscape context and temporal variation affect food web dynamics. My collaborators in this work include several recent international visitors (Drs. Andrew Gonzalez and Michel Loreau, University of Paris, and Dr. Michael Bonsall, Imperial College, London), who will be visiting UF on a regular basis. We have found in both theoretical models and laboratory microcosms that temporal variation tends to enhance the abundance of "sink" populations, which are maintained by immigration despite being excluded from local communities by interactions such as competition. In turn, these species can exert strong effects on local communities; in effect, the combination of spatial and temporal variation can increase the impact of regional processes, relative to local processes. I am also in the initial stages of developing projects with Dr. Michael Gaines and other collaborators at the University of Miami on examining spatial and temporal heterogeneity effects in the Everglades, with a specific focus on the small mammal communities living on hammock "islands." As an example of (3), I am involved with another working group at NCEAS on a project titled “Dynamics of a Complex Ecosystem: Ecology, Socio-economics and Conservation of the Serengeti.” This involves collaboration among researchers at a number of institutions who have worked on the ecology of the Serengeti in east Africa. This is a system in which a great deal is known about the biology of key players (e.g., lions, wildebeest, dominant plants, human poaching), but there has been little or no attempt to synthesize knowledge to understand how the system as a whole can respond to perturbations. I expect there to be a number of workshops and long-term visitors to UF as this research program unfolds.