Research Interests

Metapopulation Ecology - Ecologists have been slow to realize how dynamic populations can be over time. Particularly, those species which occur in "patchy" habitats are likely to exhibit turnover, that is, local extinction and subsequent recolonization. These kinds of population dynamics can have a profound impact on life histories, geographical distributions, responses to environmental change, etc. While these ideas are now ingrained into ecological thought, we still have relatively few good empirical examples of natural metapopulations. My dissertation work focused on a metapopulation system of plant-breeding frogs from Madagascar. Current work in the U.S. involves Blanchard's cricket frog (Acris crepitans blanchardi), a species apparently in decline. My work in metapopulation ecology is primarily empirical, with a particular focus on dispersal patterns, source-sink dynamics, and patterns at large spatial and temporal scales.

Systematics of Frogs - Phylogenetic information on the genealogical relationships among species provides a glimpse into the distant past. However, this information has far more value than just elucidating the history of life. These data are crucial to helping us understand why extant organisms are they way they are. Phylogenies greatly aid us in understanding pattern and process in evolutionary biology. To this end, I am interested in elucidating the historical relationships among extant anurans (frogs and toads) for its own sake, and particularly, to address questions regarding the origin of traits. Ongoing work with mantellid frogs from Madagascar using mitochondrial DNA has revealed the origin of plant-breeding and parental care in this clade (see publications). Future work may involve other plant-breeding frogs.

Biogeography -What determines the range boundaries of species? This question motivates my current work on Blanchard's cricket frog (Acris crepitans blanchardi) and intersects with my interests in metapopulation ecology. In Ohio (USA), this species occurs in the western half of the state, but not in eastern Ohio. This is despite the fact that there are no terribly obvious changes in the landscape or barriers to dispersal. So, what limits Acris to western Ohio and does the answer to this question help us address why this species is in decline? Upcoming fieldwork, experiments and life history observations (which is not nearly as well known as you might think!) will hopefully provide some answers to these questions. I also have interest in the geographical variation of ecological interactions.

Philopatry - Roughly translated from Greek, this word means "love of the fatherland". Organisms that exhibit philopatry, faithfully return to their natal area (where they were born) to reproduce. Salmon are a classic example of this phenomenon. Amphibians are also thought to exhibit philopatry, but there is little conclusive information available. There is lots of information that demonstrates site fidelity in amphibians, but often we don't know if an individual returns to the same pond to breed because it's the natal pond, or for some other reason. Answering this question will take long-term data with marked organisms and I am planning a project using wood frogs (Rana sylvatica).