Research

I research the evolutionary ecology of predator-prey interactions and of ecological niches. Within this broad range of interests, I have three main avenues of research: 1) The locomotor performance of animals, with special interest in the locomotor performance of predators and prey,  2) The causes and consequences of intraspecific diet variation, and 3) Stable isotope ecology.

 

Body Size, Temperature, and Movement


Movement is vital to the ecology of many organisms. Movement is necessary for dispersal, foraging, and finding and obtaining mates. Yet how movement fits into broader ecological theory is lacking, which is unfortunate because movement offers a direct link from physiological and neurological processes to important ecological behaviors. These processes comprise a proportion of an organism’s metabolic rate and we can therefore incorporate movement into metabolic theory, making important predictions regarding how movement is affected by such important variables as body size and temperature. Having a better understanding of how body size and temperature affect movement can help us make predictions regarding how species may react the climate change, whether it is through dispersal to new ranges or through differential thermal responses in trophic interactions.

 

Intraspecific Diet Variation


Many populations of generalist predators are composed of individuals that use a smaller subset of prey than the population as a whole. Such intraspecific diet variation has important ecological and evolutionary consequences and can be influenced by several environmental variables. The role that intraspecific diet variation plays in structuring ecological communities and influencing ecological processes, such as increasing species coexistence, increasing the species’ invasiveness, and producing resource polymorphisms that can potentially develop reproductive isolation. However, different ecological conditions can support or inhibit the amount of diet variation that occurs among individuals of a population and the importance that such variation may play in ecological communities can change over time.


 

Stable Isotope Ecology


Stable isotopes have become an invaluable tool in the ecologists toolkit, but their seeming simplicity masks important complications that can arise across trophic levels among different tissue types that are used to obtain the isotopes. Trophic discrimination occurs when consumers differentially select for heavy or lighter isotopes when incorporating them into their tissues. Different tissues incorporate new isotopes at different rates, and the rate that a tissue incorporates new isotopes determines the time period in which those isotopic data are relevant. Furthermore, laboratory studies that research trophic discrimination and incorporation rates do so in very sterile environments and these isotopic properties can vary with body size and temperature. When these complexities are not properly handled, ecological inferences will be erroneous. Oftentimes, important management decisions are made from studies that use isotopic data and it therefore vital to ensure that isotopic data is accurate as possible.