Current and historical drivers of landscape genetic structure differ in core and peripheral salamander populations

Dudaniec, Rachael Y., Spear, Stephen F., Richardson, John S. and Storfer, Andrew (2012) Current and historical drivers of landscape genetic structure differ in core and peripheral salamander populations. Plos One, 7 5: e36769.1-e36769.12. doi:10.1371/journal.pone.0036769

Author Dudaniec, Rachael Y.
Spear, Stephen F.
Richardson, John S.
Storfer, Andrew
Title Current and historical drivers of landscape genetic structure differ in core and peripheral salamander populations
Journal name Plos One   Check publisher's open access policy
ISSN 1932-6203
Publication date 2012-05-01
Sub-type Article (original research)
DOI 10.1371/journal.pone.0036769
Open Access Status DOI
Volume 7
Issue 5
Start page e36769.1
End page e36769.12
Total pages 12
Place of publication San Francisco, CA, United States
Publisher Public Library of Science
Language eng
Formatted abstract
With predicted decreases in genetic diversity and greater genetic differentiation at range peripheries relative to their cores, it can be difficult to distinguish between the roles of current disturbance versus historic processes in shaping contemporary genetic patterns. To address this problem, we test for differences in historic demography and landscape genetic structure of coastal giant salamanders (Dicamptodon tenebrosus) in two core regions (Washington State, United States) versus the species' northern peripheral region (British Columbia, Canada) where the species is listed as threatened. Coalescent-based demographic simulations were consistent with a pattern of post-glacial range expansion, with both ancestral and current estimates of effective population size being much larger within the core region relative to the periphery. However, contrary to predictions of recent human-induced population decline in the less genetically diverse peripheral region, there was no genetic signature of population size change. Effects of current demographic processes on genetic structure were evident using a resistance-based landscape genetics approach. Among core populations, genetic structure was best explained by length of the growing season and isolation by resistance (i.e. a 'flat' landscape), but at the periphery, topography (slope and elevation) had the greatest influence on genetic structure. Although reduced genetic variation at the range periphery of D. tenebrosus appears to be largely the result of biogeographical history rather than recent impacts, our analyses suggest that inherent landscape features act to alter dispersal pathways uniquely in different parts of the species' geographic range, with implications for habitat management.
Keyword Allele frequency data
Microsatellite data
Amphibian declines
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ
Additional Notes Article number e36769

Document type: Journal Article
Sub-type: Article (original research)
Collections: School of Geography, Planning and Environmental Management Publications
Official 2013 Collection
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Citation counts: TR Web of Science Citation Count  Cited 16 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 17 times in Scopus Article | Citations
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