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Landscape features can strongly influence gene flow and the strength and direction of these effects may vary across spatial scales. However, few studies have evaluated methodological approaches for selecting spatial scales in landscape genetics analyses, in part because of computational challenges associated with optimizing landscape resistance surfaces (LRS). We used the federally threatened eastern indigo snake ( Drymarchon...
Navigating the pitfalls and promise of landscape geneticsNARA Subscribed
The field of landscape genetics has been evolving rapidly since its emergence in the early 2000s. New applications, techniques and criticisms of techniques appear like clockwork with each new journal issue. The developments are an encouraging, and at times bewildering, sign of progress in an exciting new field of study. However, we suggest that the rapid expansion of landscape genetics has belied important flaws in the develop...
A species' genetic structure often varies in response to ecological and landscape processes that differ throughout the species' geographic range, yet landscape genetics studies are rarely spatially replicated. The C ope's giant salamander ( D icamptodon copei ) is a neotenic, dispersal‐limited amphibian with a restricted geographic range in the P acific northwestern USA . We investigated which landscape factors affect D . cope...
Use of resistance surfaces for landscape genetic studies: considerations for parameterization and analysisNARA Subscribed
Measures of genetic structure among individuals or populations collected at different spatial locations across a landscape are commonly used as surrogate measures of functional (i.e. demographic or genetic) connectivity. In order to understand how landscape characteristics influence functional connectivity, resistance surfaces are typically created in a raster GIS environment. These resistance surfaces represent hypothesized r...
Landscape genetics: where are we now?NARA Subscribed
Landscape genetics has seen rapid growth in number of publications since the term was coined in 2003. An extensive literature search from 1998 to 2008 using keywords associated with landscape genetics yielded 655 articles encompassing a vast array of study organisms, study designs and methodology. These publications were screened to identify 174 studies that explicitly incorporated at least one landscape variable with genetic...
Landscape genetic structure of coastal tailed frogs ( Ascaphus truei ) in protected vs. managed forestsNARA Subscribed
Habitat loss and fragmentation are the leading causes of species’ declines and extinctions. A key component of studying population response to habitat alteration is to understand how fragmentation affects population connectivity in disturbed landscapes. We used landscape genetic analyses to determine how habitat fragmentation due to timber harvest affects genetic population connectivity of the coastal tailed frog ( Ascaphus tr...
Landscape genetics of the blotched tiger salamander ( Ambystoma tigrinum melanostictum )NARA Subscribed
The field of landscape genetics has great potential to identify habitat features that influence population genetic structure. To identify landscape correlates of genetic differentiation in a quantitative fashion, we developed a novel approach using geographical information systems analysis. We present data on blotched tiger salamanders ( Ambystoma tigrinum melanostictum ) from 10 sites across the northern range of Yellowstone...
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