Rocky Mountain Research Station Publications

RMRS Online Publication - Journal Articles, External Publications, and Special Reports
sGD software for estimating spatially explicit indices of genetic diversity

Shirk, A. J.; Cushman, S. A. 2011. sGD software for estimating spatially explicit indices of genetic diversity. Molecular Ecology Resources. 11: 923-934.

Anthropogenic landscape changes have greatly reduced the population size, range and migration rates of many terrestrial species. The small local effective population size of remnant populations favours loss of genetic diversity leading to reduced fitness and adaptive potential, and thus ultimately greater extinction risk. Accurately quantifying genetic diversity is therefore crucial to assessing the viability of small populations. Diversity indices are typically calculated from the multilocus genotypes of all individuals sampled within discretely defined habitat patches or larger regional extents. Importantly, discrete population approaches do not capture the clinal nature of populations genetically isolated by distance or landscape resistance. Here, we introduce spatial Genetic Diversity (sGD), a new spatially explicit tool to estimate genetic diversity based on grouping individuals into potentially overlapping genetic neighbourhoods that match the population structure, whether discrete or clinal. We compared the estimates and patterns of genetic diversity using patch or regional sampling and sGD on both simulated and empirical populations. When the population did not meet the assumptions of an island model, we found that patch and regional sampling generally overestimated local heterozygosity, inbreeding and allelic diversity. Moreover, sGD revealed fine-scale spatial heterogeneity in genetic diversity that was not evident with patch or regional sampling. These advantages should provide amore robust means to evaluate the potential for genetic factors to influence the viability of clinal populations and guide appropriate conservation plans.

Keywords: clinal population, genetic diversity, mountain goat, sampling method, simulation

About PDFs: For best results, do not open the PDF in your Web browser. Right-click on the PDF link to download the PDF file directly to your computer. Click here for more PDF help.

Download Article

PDF File Size: 1.6 MB

Title: RMRS Other Publications: sGD software for estimating spatially explicit indices of genetic diversity
Electronic Publish Date: October 5, 2011
Last Update:
October 5, 2011

RMRS Publications | Order a publication | Contact Us