Date of Award

Spring 5-13-2016

Degree Type

Dissertation-Restricted

Degree Name

Ph.D.

Degree Program

Biological Sciences

Department

Biological Sciences

Major Professor

Johnson, Steven

Second Advisor

Sacks, Benjamin

Third Advisor

Anthony, Nicola

Fourth Advisor

Howard, Jerome

Fifth Advisor

Bell, Charles

Abstract

When new populations are first identified in a region there are multiple potential sources: introduction of a non-native species, extra-range expansion of a nearby population, or demographic growth of a previously unnoticed species. Red foxes were absent or rare in the mid-eastern portion United States until the late 1800s. Their origins potentially include natural population increase/expansion, translocations from Europe, and, eventually, 20th century fur farming. In this study I attempt to identify the relative impact of native expansion versus human mediated introductions of both colonial era European foxes and early 20th century fur-farm foxes on the establishment of red foxes in the mid-Atlantic region of the United States. I subsequently address the potential impacts of hybridization and nuclear introgression between previously separate sister taxa. Through analysis of mitochondrial DNA, I identified indigenous haplotypes, two European haplotypes, and fur-farm haplotypes; another set of haplotypes were potentially indigenous or native. In addition, I found European Y-chromosome haplotypes. Most European and fur-farm haplotypes were found near the densely human-populated coastal plain and Hudson River lowlands; most red foxes of the Appalachians and Piedmont had native eastern haplotypes. However, nuclear data does not support this division showing low genetic structure despite the broad geographic scale of our study area, attributable both to range expansion and admixture. Admixture has not had the same impact on the nuclear genome as it has in mitochondrial haplotypes leading to mito-nuclear discordance across the region. I also found evidence for differential patterns of expansion related to habitat. Specifically, the Appalachian Mountains acted as a corridor for gene flow from the northern native source into the southern Mid-Atlantic region

Rights

The University of New Orleans and its agents retain the non-exclusive license to archive and make accessible this dissertation or thesis in whole or in part in all forms of media, now or hereafter known. The author retains all other ownership rights to the copyright of the thesis or dissertation.