How will global change affect interactions between species?
As the climate changes, so do interactions between species. I have been particularly interested in how climatic warming may alter competition between ant species. Using a warming manipulation, I am working to examine how increasing temperature may alter foraging activity and the timing of foraging across an assemblage of competing ant species.
I am also interested in how these shifts in ant foraging activity may alter mutualisms between ants and plants, including seed dispseral.
Exotic species also have the potential to disrupt ant-mediated seed dispersal. My research has examined the potential for three exotic ant species (the red imported fire ant, the Argentine ant, and the Asian needle ant) to reduce both the quality and quantity of seed dispersal in invaded ecosystems.
What mechanisms maintain diversity in ant communities?
I am interested in understanding the mechanisms that allow ant species to coexist. I have tested the importance of mechanisms ranging from the dominance - discovery tradeoff to niche segregation in an eastern deciduous forest, and have found strong evidence that ants in this system are segregated by time. More aggressive ants forage more commonly at night, while subordinate ants forage in higher numbers during the day.
I am currently working to better our understanding of the nature and importance of behavioral dominance hierarchies in ant communities. Combining field studies and a review of the literature, I seek to explain how these hierarchies have been used, and what they might be able to tell us about the nature of ant communities.
How variable are interspecific interactions in space and time?
Using a multi-year, multi-site grassland restoration experiment in northern California, I am studying the extent to which the strength and outcome of competitive interactions is conditional on the abiotic environment. I am also examining the importance of priority effects in grassland plant communities, and how long the signature of the competitive advantage conferred by priority is evident in the composition of plant communities.