Mahurin Honors College Capstone Experience/Thesis Projects



Document Type



Habitat connectivity affects the distribution of genetic diversity among populations by influencing the movements of individuals and the resulting pattern of gene flow across landscapes. It has become evident that amphibians are experiencing a period of worldwide population declines brought about by environmental change. An understanding of the effects of habitat structure on landscape connectivity is important for developing effective amphibian conservation strategies. The purpose of this study is to investigate the effect of landscape characteristics on gene flow and population structure of the marbled salamander (Ambystoma opacum) in Mammoth Cave National Park, Kentucky, USA. Salamander larvae were sampled from 50 ponds and screened at eight microsatellite loci to estimate genetic population structure. We used the R package ResistanceGA to build and evaluate models of landscape resistance using five different habitat categories: coniferous forest, dry deciduous forest, wet deciduous forest, human influence, and surface water. Our data reveal strong support for an ‘isolation by distance’ model in which interpond distances are a reliable predictor of the pattern of gene flow observed.

Advisor(s) or Committee Chair

Jarrett Johnson, Ph.D.


Ecology and Evolutionary Biology | Other Genetics and Genomics | Population Biology