Monitoring temporal changes in genetic diversity within populations can provide vital information on future viability. The dusky gopher frog, Lithobates sevosus, exists in isolation with an estimated population size of 100-200 individuals, and previous research has shown that low genetic variability exists as a consequence of isolation and population size reduction. However, the temporal changes in genetic variation are not known. Therefore, my objectives were to (1) determine temporal trends in population genetic variation and implications for long-term viability of L. sevosus and (2) estimate effective population size. To accomplish these objectives, egg samples collected from 1997 to 2014 were genotyped for nine microsatellite loci. Observed and expected heterozygosity, allelic richness, and Wright's inbreeding coefficient were calculated for each year and differences between sample years were assessed. Additionally, overall and pair-wise FST values were calculated to test for temporal genetic structuring. To estimate effective population size, two single-sample estimators (Tallmon et al. 2008; Waples and Do 2008) and two temporal estimators (Waples 1989; Wang 2001) were used. The results show a stable, but low, level of genetic variation. Weak genetic structure (FST = 0.023 (95% CI 0.006-0.043)) was found among years, which can be attributed to the increased effects of genetic drift in small populations. L. sevosus currently has an estimated effective population size between 32.99-58.6 individuals. The ratios of effective size to census size per year are fairly large (~0.5) and exhibit an increasing trend over time, which could possibly be explained by genetic compensation--or the lessening of genetic variation reduction in times with low population numbers. This research indicates the current management programs in place for L. sevosus have been effective at maintaining the genetic diversity present in the population; however, additional strategies need to be implemented to increase genetic diversity.
","abstract_html":"<p>Monitoring temporal changes in genetic diversity within populations can provide vital information on future viability. The dusky gopher frog, Lithobates sevosus, exists in isolation with an estimated population size of 100-200 individuals, and previous research has shown that low genetic variability exists as a consequence of isolation and population size reduction. However, the temporal changes in genetic variation are not known. Therefore, my objectives were to (1) determine temporal trends in population genetic variation and implications for long-term viability of L. sevosus and (2) estimate effective population size. To accomplish these objectives, egg samples collected from 1997 to 2014 were genotyped for nine microsatellite loci. Observed and expected heterozygosity, allelic richness, and Wright's inbreeding coefficient were calculated for each year and differences between sample years were assessed. Additionally, overall and pair-wise FST values were calculated to test for temporal genetic structuring. To estimate effective population size, two single-sample estimators (Tallmon et al. 2008; Waples and Do 2008) and two temporal estimators (Waples 1989; Wang 2001) were used. The results show a stable, but low, level of genetic variation. Weak genetic structure (FST = 0.023 (95% CI 0.006-0.043)) was found among years, which can be attributed to the increased effects of genetic drift in small populations. L. sevosus currently has an estimated effective population size between 32.99-58.6 individuals. The ratios of effective size to census size per year are fairly large (~0.5) and exhibit an increasing trend over time, which could possibly be explained by genetic compensation--or the lessening of genetic variation reduction in times with low population numbers. This research indicates the current management programs in place for L. sevosus have been effective at maintaining the genetic diversity present in the population; however, additional strategies need to be implemented to increase genetic diversity. </p>","abstract_has_math":false,"creators":["Hinkson, Kristin Michelle"],"institution":"Eastern Kentucky University","degree_name":"Master of Science (MS)","degree_level":"Master's","degree_discipline":"Biological Sciences","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2015,"date_issued":"2015-01-01T08:00:00Z","date_published":"2015-01-01T08:00:00Z","updated_at":"2026-07-24T02:15:25Z","subjects":["effective size","endangered species","genetic structure","Lithobates sevosus","temporal variation","Ecology and Evolutionary Biology"],"languages":[],"rights":["Copyright 2015 Kristin Michelle Hinkson"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://encompass.eku.edu/etd/274","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Hinkson, Kristin Michelle"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:publisher","label":"Institution","values":["Encompass Digital Archive, Eastern Kentucky University"]},{"key":"dc:type","label":"Dc Type","values":["Master Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biological Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Master's"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science (MS)"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Eastern Kentucky University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["effective size","endangered species","genetic structure","Lithobates sevosus","temporal variation","Ecology and Evolutionary Biology"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2015 Kristin Michelle Hinkson"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://encompass.eku.edu/etd/274"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Monitoring temporal changes in genetic diversity within populations can provide vital information on future viability. The dusky gopher frog, Lithobates sevosus, exists in isolation with an estimated population size of 100-200 individuals, and previous research has shown that low genetic variability exists as a consequence of isolation and population size reduction. However, the temporal changes in genetic variation are not known. Therefore, my objectives were to (1) determine temporal trends in population genetic variation and implications for long-term viability of L. sevosus and (2) estimate effective population size. To accomplish these objectives, egg samples collected from 1997 to 2014 were genotyped for nine microsatellite loci. Observed and expected heterozygosity, allelic richness, and Wright's inbreeding coefficient were calculated for each year and differences between sample years were assessed. Additionally, overall and pair-wise FST values were calculated to test for temporal genetic structuring. To estimate effective population size, two single-sample estimators (Tallmon et al. 2008; Waples and Do 2008) and two temporal estimators (Waples 1989; Wang 2001) were used. The results show a stable, but low, level of genetic variation. Weak genetic structure (FST = 0.023 (95% CI 0.006-0.043)) was found among years, which can be attributed to the increased effects of genetic drift in small populations. L. sevosus currently has an estimated effective population size between 32.99-58.6 individuals. The ratios of effective size to census size per year are fairly large (~0.5) and exhibit an increasing trend over time, which could possibly be explained by genetic compensation--or the lessening of genetic variation reduction in times with low population numbers. This research indicates the current management programs in place for L. sevosus have been effective at maintaining the genetic diversity present in the population; however, additional strategies need to be implemented to increase genetic diversity.
"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:source","label":"Dc Source","values":["Encompass Digital Archive: Online Theses and Dissertations"]},{"key":"dc:title","label":"Title","values":["Temporal Comparisons on the Genetic Variation of the Dusky Gopher Frog (Lithobates sevosus)"]}]}],"canonical_facts":{"dc:creator":["Hinkson, Kristin Michelle"],"dc:description.abstract":["Monitoring temporal changes in genetic diversity within populations can provide vital information on future viability. The dusky gopher frog, Lithobates sevosus, exists in isolation with an estimated population size of 100-200 individuals, and previous research has shown that low genetic variability exists as a consequence of isolation and population size reduction. However, the temporal changes in genetic variation are not known. Therefore, my objectives were to (1) determine temporal trends in population genetic variation and implications for long-term viability of L. sevosus and (2) estimate effective population size. To accomplish these objectives, egg samples collected from 1997 to 2014 were genotyped for nine microsatellite loci. Observed and expected heterozygosity, allelic richness, and Wright's inbreeding coefficient were calculated for each year and differences between sample years were assessed. Additionally, overall and pair-wise FST values were calculated to test for temporal genetic structuring. To estimate effective population size, two single-sample estimators (Tallmon et al. 2008; Waples and Do 2008) and two temporal estimators (Waples 1989; Wang 2001) were used. The results show a stable, but low, level of genetic variation. Weak genetic structure (FST = 0.023 (95% CI 0.006-0.043)) was found among years, which can be attributed to the increased effects of genetic drift in small populations. L. sevosus currently has an estimated effective population size between 32.99-58.6 individuals. The ratios of effective size to census size per year are fairly large (~0.5) and exhibit an increasing trend over time, which could possibly be explained by genetic compensation--or the lessening of genetic variation reduction in times with low population numbers. This research indicates the current management programs in place for L. sevosus have been effective at maintaining the genetic diversity present in the population; however, additional strategies need to be implemented to increase genetic diversity.
"],"dc:format":["application/pdf"],"dc:identifier":["https://encompass.eku.edu/etd/274"],"dc:publisher":["Encompass Digital Archive, Eastern Kentucky University"],"dc:rights":["Copyright 2015 Kristin Michelle Hinkson"],"dc:source":["Encompass Digital Archive: Online Theses and Dissertations"],"dc:subject":["effective size","endangered species","genetic structure","Lithobates sevosus","temporal variation","Ecology and Evolutionary Biology"],"dc:title":["Temporal Comparisons on the Genetic Variation of the Dusky Gopher Frog (Lithobates sevosus)"],"dc:type":["Master Thesis"],"thesis:degree_discipline":["Biological Sciences"],"thesis:degree_level":["Master's"],"thesis:degree_name":["Master of Science (MS)"],"thesis:institution_name":["Eastern Kentucky University"]},"updated_at":"2026-07-24T02:15:25Z"}