Dataset Information

Fine-scale genetic structure among greater sage-grouse leks in central Nevada.

ABSTRACT: Mating systems that reduce dispersal and lead to non-random mating might increase the potential for genetic structure to arise at fine geographic scales. Greater sage-grouse (Centrocercus urophasianus) have a lek-based mating system and exhibit high site fidelity and skewed mating ratios. We quantified population structure by analyzing variation at 27,866 single-nucleotide polymorphisms in 140 males from ten leks (within five lek complexes) occurring in a small geographic region in central Nevada.Lek complexes, and to a lesser extent individual leks, formed statistically identifiable clusters in ordination analyses, providing evidence for fine-scale geographic genetic differentiation. Lek geography predicted genetic differentiation even at a small geographic scale, which could be sharpened by strong site fidelity. Relatedness was also higher among individuals within lek complexes (and leks), suggesting that reproductive skew, where few males participate in most of the successful matings, could also potentially contribute to genetic differentiation. Models incorporating a habitat resistance surface as a proxy for potentially reduced movement due to landscape features indicated that both geographic distance and habitat suitability (i.e. preferred habitat) predicted genetic structure, with no significant effect of man-made barriers to movement (i.e. power lines and roads). Finally, we illustrate how data sets containing fewer loci (<4000) had less statistical precision and failed to detect the full degree of genetic structure.Our results suggest that habitat features and lek site geography of sage-grouse shape fine scale genetic structure, and highlight how larger data sets can have increased precision and accuracy for quantifying ecologically relevant genetic structure over small geographic scales.

SUBMITTER: Jahner JP

PROVIDER: S-EPMC4908695 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Fine-scale genetic structure among greater sage-grouse leks in central Nevada.

Jahner Joshua P JP Gibson Daniel D Weitzman Chava L CL Blomberg Erik J EJ Sedinger James S JS Parchman Thomas L TL

BMC evolutionary biology 20160614 1

<h4>Background</h4>Mating systems that reduce dispersal and lead to non-random mating might increase the potential for genetic structure to arise at fine geographic scales. Greater sage-grouse (Centrocercus urophasianus) have a lek-based mating system and exhibit high site fidelity and skewed mating ratios. We quantified population structure by analyzing variation at 27,866 single-nucleotide polymorphisms in 140 males from ten leks (within five lek complexes) occurring in a small geographic regi ...[more]

PMID: 27301494

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Dataset Information

Fine-scale genetic structure among greater sage-grouse leks in central Nevada.

Publications

Fine-scale genetic structure among greater sage-grouse leks in central Nevada.

Similar Datasets

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