My research interests encompass areas of ecology, evolutionary ecology, and host-parasite interactions. I am also broadly interested in the ecology and evolution of infectious diseases, including parasite transmission dynamics.
Experimental Evolution: Disease models often classify species as either parasitic or non-parasitic, even though levels of parasitism vary continuously in nature. I am interested in the life-history evolution of parasites that express variation in host exploitation strategies, and the selective pressures that lead to increasing infectivity. Facultative parasites present a unique opportunity for addressing these questions because they operate on the margin between free-living and parasitic life styles. The free-living stages of the ectoparasitic mite (Macrocheles subbadius) feed and reproduce on highly ephemeral habitats; however, mites can switch to a parasitic life-style under certain conditions, attaching to and feeding on cactophilic drosophilid hosts. We use this highly tractable model system to study evolutionary processes in the laboratory. The aim is to understand how the transition to parasitism occurs on a ecological time scale (i.e., phenotypic plasticity) and identify the conditions that drive or constrain the evolution of infection along this continuum.
Physiological Ecology: This is an interdisciplinary field of science that incorporates the mechanistic thinking and techniques of animal physiology to address ecological questions. A central question is how the energetic demands of an organism are influenced by environmental stressors, including parasitism. Parasites can have potentially strong effects on host physiology, metabolism, and energy budgets. We use flow-through respirometry to investigate the metabolic costs of parasitism during the pre-infection period (i.e., due to parasite-avoidance) and as a consequence of infection itself.