Our laboratory group seeks to uncover the general principles that organize ecological communities and ecosystems. We focus on phytoplankton and zooplankton, the microscopic plants and animals at the base of lake and ocean food webs. Plankton communities are an ideal focus for this work, because they show striking patterns in space, time, and organization, and are easily manipulated in the lab and field. From a practical point of view, freshwater plankton are important determinants of water quality and marine phytoplankton play major roles in global biogeochemical cycles and perform about half the planet’s primary productivity.