Document Type
Thesis
Abstract
This study focuses on the response of the bivalve genus Venericardia to dramatic climate change during the Paleogene, focusing on specimens from the United States Gulf Coastal Plain. This investigation of the relationship between climate and evolutionary change in venericard bivalves is useful because it assesses the long-term effects of climate change and provides a basis for future extrapolation of taxonomic response to climate variation. This information is particularly relevant today with the predicted global temperature increase because it provides an idea of how a taxon might respond to climate change. This study analyzed three specific aspects of venericard bivalves: geographic range, diversity and body size. Specimens for the body size study included individuals from 14 species, ranging from 5 and 43 specimens for each species, from museum collections and previously collected specimens. They range from Paleocene to Oligocene in age and are all from the Gulf Coastal Plain. Digital photographs were taken and landmark data were collected for the body size component of the study. Body size was calculated centroid size of each specimen. For the diversity and geographic range components of the study, occurrence data were compiled at the species level from published monographs. Boundary-crosser methods were used to quantify diversity based on the stratigraphic range data of each species. These occurrence data were also transformed into latitude and longitude data on GIS maps to see whether geographic range changed over time and in response to climate change.
Date Awarded
2009
Department
Geology
Advisor 1
Rowan Lockwood
Recommended Citation
Ohman, Karin A., "Shifts in Diversity, Geographic Range, and Body Size in Venericardia during the Paleogene of the Gulf Coastal Plain" (2009). Geology Senior Theses. William & Mary. Paper 219.
https://scholarworks.wm.edu/geologyseniors/219
