The California Academy of Sciences produced a video that uses UCMP's Understanding Science website's How Science Works flowchart to map the discovery of a new spider family. UCMP Education and Public Programs team leaders Judy Scotchmoor and Lisa White have starring roles! Watch the video at Science360.
Archive for January 2013
Abstract: Building up the biota in novel environments: insights using the fossil record of epeiric seas
Throughout the Phanerozoic, times of rising sea level were often accompanied by the development of shallow seas on the continents. These epeiric seas formed relatively rapidly in geologic time and differed physically from open marine habitats, with shallower depths and altered salinity, temperature, and circulation. The build-up of diversity within these new habitats must result from one or more of the following processes: uninhibited dispersal of open marine taxa, limited dispersal with ecological filtering of open marine taxa, and one or more rounds of in situ speciation. The paleontological record allows discrimination between these processes and additionally chronicles any accompanying anagenesis. Despite the extensive representation of epeiric seas in the fossil record, little has been done to characterize and determine the source of epeiric biotas. My focus is on ammonites in the Late Cretaceous, characterized by high sea levels and inland flooding, including creation of a seaway across North America between the Arctic Ocean and the Caribbean Sea. Ammonites are an ideal study group because they are fast evolving, abundant and well preserved — features that allow for fine temporal and spatial control. Using geographic and temporal distributions and body size data for over 500 species of ammonite, I present spatial patterns in diversity and ecology of Cretaceous ammonites across epeiric and non-epeiric habitats to determine the relative importance of the various processes that build diversity in novel environments.