Humans are currently the dominant force affecting the earth system. Arguably the most irreversible change we are making is the ongoing extinction of species on global and local scales. The consequences of this diversity loss for ecosystem processes, and the associated services they provided to us (plant and animal production, nursery support of fisheries, nutrient cycling, etc.), have been a major focus of interest and controversy in recent years. We study the communities associated with Chesapeake Bay seagrasses as a model system for understanding links between biodiversity, food-web processes, and ecosystem functioning. Eelgrass (Zostera marina) beds are important and threatened coastal ecosystems throughout the northern hemisphere. In these and many other shallow aquatic ecosystems, grazing of algae by small, mobile invertebrates (mesograzers) appears critical in fostering dominance by rooted plants and large seaweeds, which in turn provide essential habitat and food for economically important fish, shellfish, and waterfowl species (see Submersed Aquatic Vegetation in the Chesapeake Bay for more information). Mesograzers play potentially pivotal roles in vegetated marine habitats worldwide, yet their community-level impacts are poorly understood. Our research investigates both the "top-down" impact of mesograzers on plant communities, and their "bottom-up" importance as trophic links to fishes and other predators. We use a mesocosm and field experiments, time series analysis from field monitoring, and studies of grazer population dynamics and feeding biology. This long-term research has been supported by the National Science Foundation (Biological Oceanography program).
The symbiotic shrimp genus Synalpheus is among the most diverse genera of crustaceans, with >100 described species, and is abundant on coral reefs worldwide. Its species richness is matched by an intriguing diversity in life history, host specificity, and most notably its broad range of social systems, with some species living as monogamous pairs while other species live in colonies of hundreds of individuals with a single female breeding-the only known case of eusociality among marine animals. Our research is clarifying this group's difficult taxonomy, with descriptions of about 20 new species so far, as well as their phylogenetic relationships. The new phylogeny has opened the door to the strong potential of Synalpheus as a model system for comparative research on the evolution of origins of life history, social systems, speciation mechanisms, and geographc patterns of marine biodiversity. This research has been supported by the National Science Foundation, the Smithsonian Institution (Caribbean Coral Reef Ecosystem program), and the National Geographic Society.
Recent research has shown that diverse ecosystems often are more stable and more productive than species-poor systems. Can this principle inform our approach to solving the major problems of our time-growing pollution and shrinking fuel supplies? We are exploring the possibility of using engineered communities of wild diverse algae as a natural solution to sequestering excess nutrients and contaminants from waterways, while simultaneously producing a feedstock for conversion into biofuels. This effort is being seeded by funds from energy company StatoilHydro and involves a collaboration between researchers from VIMS, The College of William and Mary, the Smithsonian Institution, the University of Arkansas, the University of Maryland, and Blackrock Energy advisors.