ECIMMEE Project: The evolution of ecosystem function in phytoplankton-virus communities
Marine microbes play a prominent role in ocean ecosystems and global biogeochemistry, with phytoplankton in particular accounting for about half of global primary production. When we zoom in on the organisms performing these functions, we find immense diversity, from high genetic diversity within ‘species’ to deep phylogenetic diversity across the tree of life. Interactions like competition, predation and parasitism are ubiquitous, leading to complex network dynamics. Furthermore, the short generation times of microbes means that rapid evolution is possible and probably common. There is a critical need to develop and test general theory that explains how these diverse, coevolving communities are structured, and how they drive change in ecosystem function across changing environmental conditions.
This research project will address these questions in communities of phytoplankton and their viruses. Recent work has argued that host and virus genetic diversity may be maintained by host tradeoffs between competitive ability and resistance to infection and by viral tradeoffs between breadth of host range and infection success. An important implication is that viruses may alter the ecological function and functional diversity of host populations, and these effects may vary in systemic ways across environments. Furthermore, it is commonly argued that the immense taxonomic diversity in microbial systems is also maintained by viruses and that coexistence between species may depend on tradeoffs within species that affect competitive ability. Ultimately, the effect of viruses on large-scale ecosystem processes will be derived from these population and community eco-evolutionary dynamics. This project will address these questions by combining experimental evolution, trait-based models of eco-evolutionary dynamics and long-term culture experiments with diverse phytoplankton and virus isolates.
Kyle Edwards is an assistant professor in the Department of Oceanography at the University of Hawai’i at Mānoa. His research combines theoretical and empirical approaches to the ecology and evolution of microbial communities. Particular research interests include fundamental constraints on organismal traits, how community structure and diversity emerge from these underlying rules, and the consequences for ecosystem and biogeochemical processes. Edwards received a B.A. in biological sciences with honors from the University of Chicago (2003) and a Ph.D. in population biology from the University of California, Davis (2010). Before joining the faculty at UHM he was a postdoc at the Kellogg Biological Station at Michigan State University.