Bivalves (clams, oysters, mussels, scallops, etc.) are a diverse and familiar group of mollusks with an old and well-preserved fossil record, important ecological roles in marine and freshwater ecosystems, and economic roles including fisheries, the ornament industry, and health sciences. Diversity-wise, bivalves – with 20,000-30,000 living species – are the second largest class of living mollusks, which in turn constitute the second largest animal phylum and the largest in the marine realm.
Despite the ubiquitousness of bivalves, past efforts to study and understand their evolution have been insufficiently coordinated and little consensus has been reached. A grant from the National Science Foundation’s Assembling the Tree of Life Program has been awarded to Dr. Rüdiger Bieler of the Field Museum of Natural History (Chicago, Illinois), Dr. Gonzalo Giribet of the Museum of Comparative Zoology (Harvard University, Cambridge, Massachusetts), Dr. Paula M. Mikkelsen of Paleontological Research Institution (Ithaca, New York), and collaborators as part of a multi-institutional effort to assemble the bivalve tree of life. For this, we are undertaking a fresh look at bivalve anatomy (with special focus on gill and stomach anatomy, shell ultrastructure, and sperm morphology) and we will study selected molecular markers (genes) for the same species investigated morphologically to be able to understand bivalve evolution in an integrated fashion. While national and international project teams coordinated at FMNH and MCZ assemble morphological and molecular data, respectively, in levels of detail never before attempted, PRI participants will concentrate on outreach efforts to engage various audiences in the project’s results and in evolutionary science as a whole.