My research focuses on two pervasive and inter-related forms of biological change: disease emergence and species invasions. Both have important consequences not only for individuals and populations, but for entire ecological communities and ecosystem processes. Invasions and disease also have costly economic and health repercussions for human societies. I use long-term data, ecological experiments and modeling approaches to examine the factors that drive disease emergence and biological invasions, and how changes in disease and invasion levels, in turn, affect community interactions and ecosystem processes in aquatic environments. Study systems with which I have the most experience include trematode-induced malformations in amphibians, fungal pathogens of zooplankton ( Daphnia ) and the aquatic invaders Bythotrephes longimanus (spiny water flea) and Bellamya chinensis (Chinese mystery snail). My current research program is directed at three inter-related focal areas: (i) Cross-scale drivers of disease emergence; (ii) The functional role of disease in ecosystems; and (iii) Interactions among invasions and habitat alteration. All have immediate relevance to both fundamental questions in ecology and applied conservation issues.
Johnson, P. T. J., Chase, J. M., Dosch, K. L., Gross, J., Hartson, R. B., Larson, D., Sutherland, D. R. and S. R. Carpenter (2007).
Available Positions in the Johnson Lab
The Johnson Laboratory is actively seeking applications for two new graduate student positions. These positions are scheduled to begin in the Summer (ideally) or Fall of 2015. Please click here for additional information.