dc.contributor.author	Ashraf, Ali Jamal
dc.coverage.spatial	Southeastern States	en_US
dc.date.accessioned	2025-07-15T18:32:09Z
dc.date.available	2025-07-15T18:32:09Z
dc.date.issued	2025-06-13
dc.identifier.other	654766ec-c984-43ef-9cb7-6044ca4af008	en_US
dc.identifier.uri	https://hdl.handle.net/10428/7551
dc.description.abstract	Barriers to dispersal often cause evolutionary divergence. In the present, identification of geographic boundaries between lineages can indicate the historic presence of biogeographic barriers. In eastern North America, these patterns often arose during periods when changes in climate accompanied the origin of topographic features that hinder gene flow through expansion of river systems, changes in sea level, and restriction of organisms to refugia. However, organisms’ responses to changing landscapes is often complex. Not all taxa, even those with similar ecologies, exhibit effects on gene flow from the same changes in geographic features and climate; there is often nuance in these evolutionary shifts. In this study, I use the banded water snake, Nerodia fasciata, as a model to test for phylogeographic structure associated with potential biogeographic barriers. While this species is found throughout the U.S. southeastern coastal plain region, previous phylogeographic research has been limited to Florida, a deficiency I address here. I sequenced the mitochondrial gene cytochrome b (cytb) and the nuclear gene prolactin receptor (PRLR) for phylogenetic analysis across the range of N. fasciata. Additionally, biogeographic modeling was used to investigate the historic distributions of this group. Results indicate that this species first diversified during the late Miocene and early Pliocene and may have historically been isolated to a glacial refugium in the western part of its range and to the Florida peninsula by high sea levels. These findings are consistent with patterns observed in certain other snake species distributed throughout the American southeast. Phylogeographic breaks were not found at major river systems, while ranges of the subspecies of this group better fit the distributions of its major mitochondrial lineages. This research contributes new information on the systematics of N. fasciata and helps to explore how organisms respond to changing geography across continental land masses, providing a model for testing southeastern biogeography in other taxa.	en_US
dc.format.extent	1 electronic record. PDF/A document, 56 pages, 9359487 bytes.	en_US
dc.format.mimetype	application/pdf	en_US
dc.language.iso	en_US	en_US
dc.rights	This dissertation is protected by the Copyright Laws of the United States (Public Law 94-553, revised in 1976). Consistent with fair use as defined in the Copyright Laws, brief quotations from this material are allowed with proper acknowledgement. Use of the materials for financial gain with the author's expressed written permissions is not allowed.	en_US
dc.subject	Academic theses	en_US
dc.subject	Animal distribution	en_US
dc.subject	Biogeography	en_US
dc.subject	Electronic records	en_US
dc.subject	Evolution (Biology)	en_US
dc.subject	Herpetology	en_US
dc.subject	Nerodia	en_US
dc.subject	Phylogeny	en_US
dc.subject	Phylogeography	en_US
dc.subject	Snakes	en_US
dc.subject	Southeastern States	en_US
dc.title	Snakes on the Plain: Biogeographic Patterns in Banded Watersnakes (Nerodia fasciata) across the Southeastern Coastal Plain	en_US
dc.type	Thesis	en_US
dc.contributor.department	Department of Biology of the College of Science and Mathematics	en_US
dc.description.advisor	Lokdarshi, Ansul
dc.description.committee	Phillips, John
dc.description.committee	Safer, Adam
dc.description.degree	M.S.	en_US
dc.description.major	Biology	en_US