Maintaining intraspecific variation is important for populations’ long-term success and is increasingly being recognized as an important conservation goal. Populations in anthropogenically fragmented habitats may lose variation rapidly via genetic drift, particularly in small fragments with a high ratio of edge to interior habitat. We studied the population and ecological genetic effects of habitat fragmentation on both a foundation plant, Spartina patens, and a dependent herbivore, Tumidagena minuta, using a naturally fragmented, salt marsh model system. We employed microsatellite marker analyses to estimate various measures of genetic variation, including allelic richness and heterozygosity, and to estimate the strength of genetic drift using estimates of effective population size (Ne). To achieve this, we developed a new program to estimate Ne and developed new markers for S. patens from genome sequence data. We found lower S. patens genetic variation and lower T. minuta Ne near the S. alterniflora edges, indicating that T. minuta experience stronger genetic drift near edges. These findings reinforce the importance of habitat patch shape in influencing populations.
|Advisor:||Wimp, Gina M.|
|Commitee:||Armbruster, Peter, Weiss, Martha|
|School Location:||United States -- District of Columbia|
|Source:||MAI 56/04M(E), Masters Abstracts International|
|Keywords:||Genetic drift, Habitat fragmentation, Microsatellite, Salt marsh, Spartina patens, Tumidagena minuta|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be