9704806 Ivany Deciphering the complex relationship between evolutionary change and environmental change requires a detailed and simultaneous record of both variables so that patterns in each can be compared. If the records dovetail, then there is compelling evidence for the role of environment in influencing the direction of evolutionary change. The P.I. will explore this issue with a case study in the Eocene Gulf Coastal Plain. She will construct a temperature curve specific to the coastal region by analyzing the isotopic composition of biogenic carbonates. Secular trends in both temperature and seasonality associated with mid-Eocene to Oligocene global cooling will be examined through geochemical analysis of biogenic carbonates and careful microsampling of growth lines in organisms showing accretionary growth.
