PI's will continue research on the role of intrinsic factors in evolutionary rates and modes of marine invertebrates, centering on the bivalves and shelled gastropods in two regions: the Neogene (including Recent) of the eastern Pacific and the Late Cretaceous of the Gulf and Atlantic Coastal Plain. PI's will refine databases on developmental modes and geographic, stratigraphic and bathymetric ranges, add data on body size and population densities and collect more data on patterns of extinction, survival and rebound for European mollusks around the Cretaceous-Tertiary (K-T) boundary. PI's will test hypotheses on: separate and combined effects of geographic range, developmental modes, body size, population density, and preservation potential on evolutionary rates and patterns; relation of those patterns to bathymety and latitude; evolutionary trends in body size and the frequency of Cope's Rule (broadly vs narowly defined); and similarity of survivorship and rebound patterns at the K-T boundary in Europe and North America, and their relation to the background patterns as listed above.
