Bivalve molluscs (e.g., clams, oysters, scallops) are among the most important members of bottom-dwelling communities, both for their environmental impacts and commercial value. These animals possess highly efficient and complicated mechanisms for filtering the water around them, and capturing and sorting particles therein. Their feeding processes strongly couple water-column and bottom communities, and can influence the general "health" of near-shore ecosystems. Bivalves are well adapted for selecting between living and non-living particles that they filter from the water, ingesting some and rejecting others back into the environment. Because of their key role in the marine environment, it is important to understand the mechanisms by which bivalves discriminate among particles and the factors that control this process. In this research, scientists from two universities will collaborate to elucidate how bivalves sort food particles obtained from the environment. Based on their recently developed assays, the researchers have developed several lines of research that will allow them to investigate the bases of selection at the cell and organ level. In particular, they will study the interactions between particles and the feeding organs, including: a) non-specific physical and chemical interactions (e.g., charge, wettability, density); b) specific chemical interactions (e.g., sugar-lectin associations); c) behaviorally mediated interactions brought about by chemoreception and changes in the activity of particle-transport cilia. Understanding the factors that control diet selection has provided important information on a range of biological systems including interspecific interactions, marine community structure and bioenergetics. The proposed research represents the first step in defining the underlying mechanisms of diet selection in bivalves and will significantly advance an understanding of this fundamental process. This study will also add to the growing body of knowledge of lectin-based recognition systems in animals. The researchers will train graduate and undergraduate students who will be involved in various aspects of the research and will participate in scientific conferences. Results will be disseminated through scientific literature, conferences, and articles for non-specialists. The research team will partner with Connecticut's COSEE-TEK to provide technology-based educational experiences for formal (e.g., high school teachers) and informal (e.g., aquarium staff) educators. Educators will receive basic training in the operation of instruments used in the proposed research and learn how they can be applied to the study of marine organisms.
