I am a quantitative ecologist, studying how plasticity and evolution mediate the response of populations and communities to natural and anthropogenic environmental change. I both develop and test ecological and evolutionary theory, using empirical data and modern computational statistical approaches. I explore these ideas in the context of studying how changes in temperature, nutrients, and light affect phytoplankton (globally important photosynthetic microbes) over time scales from hours to centuries, and in habitats from beakers to oceans. This emphasis allows me to advance basic ecology while addressing applied questions, including predicting the effects of climate change on communities and ecosystems.