Defense Date


Document Type


Degree Name

Master of Science



First Advisor

Rodney Dyer


Global temperature changes are predicted to influence the distributions of plants and can have significant consequences for population genetic structure. Both the nature of these consequences and the processes that shape them are of interest for both conservation genetics and the development of realistic management programs. Rapid range expansion occurs on short temporal scales not conducive to conventional phylogeographical analyses. This paper presents the findings from a population genetic study of the invasive grass Microstegium vimineum Trin. A. Camus throughout the James River Basin of Virginia. Genotypic analysis using Amplified Fragment Length Polymorphism (AFLP) molecular markers were used to test for evidence of rapid range expansion and the effects associated with colonization and spread of Microstegium vimineum. Within the James River Basin three genetically distinct clusters were identified that were not clearly associated with natural geographic boundaries and recent founder events were also inferred. The James River Basin also appears to act as a corridor for long-distance dispersal events. These findings contribute to our knowledge of the genetic consequences of rapid range expansion for invasive species, and more importantly, native species. Contrary to several studies, the present research also indicates that long-distance dispersal is not rare and can be a major contributor to the genetic structure following range expansion.


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Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

August 2009

Included in

Biology Commons