Show simple item record

dc.contributor.authorStrand, Allan E.  Concept link
dc.contributor.authorWilliams, Larissa M.  Concept link
dc.contributor.authorOleksiak, Marjorie F.  Concept link
dc.contributor.authorSotka, Erik E.  Concept link
dc.date.accessioned2012-11-20T20:16:54Z
dc.date.available2012-11-20T20:16:54Z
dc.date.issued2012-09-26
dc.identifier.citationPLoS ONE 7 (2012): e45138en_US
dc.identifier.urihttps://hdl.handle.net/1912/5570
dc.description© The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS ONE 7 (2012): e45138, doi:10.1371/journal.pone.0045138.en_US
dc.description.abstractA common geographical pattern of genetic variation is the one-dimensional cline. Clines may be maintained by diversifying selection across a geographical gradient but can also reflect historical processes such as allopatry followed by secondary contact. To identify loci that may be undergoing diversifying selection, we examined the distribution of geographical variation patterns across the range of the killifish (Fundulus heteroclitus) in 310 loci, including microsatellites, allozymes, and single nucleotide polymorphisms. We employed two approaches to detect loci under strong diversifying selection. First, we developed an automated method to identify clinal variation on a per-locus basis and examined the distribution of clines to detect those that exhibited signifcantly steeper slopes. Second, we employed a classic -outlier method as a complementary approach. We also assessed performance of these techniques using simulations. Overall, latitudinal clines were detected in nearly half of all loci genotyped (i.e., all eight microsatellite loci, 12 of 16 allozyme loci and 44% of the 285 SNPs). With the exception of few outlier loci (notably mtDNA and malate dehydrogenase), the positions and slopes of Fundulus clines were statistically indistinguishable. The high frequency of latitudinal clines across the genome indicates that secondary contact plays a central role in the historical demography of this species. Our simulation results indicate that accurately detecting diversifying selection using genome scans is extremely difficult in species with a strong signal of secondary contact; neutral evolution under this history produces clines as steep as those expected under selection. Based on these results, we propose that demographic history can explain all clinal patterns observed in F. heteroclitus without invoking natural selection to either establish or maintain the pattern we observe today.en_US
dc.description.sponsorshipThis work was supported by the National Science Foundation (DEB-0919064 and IOS-1052262en_US
dc.format.mimetypeapplication/pdf
dc.language.isoen_USen_US
dc.publisherPublic Library of Scienceen_US
dc.relation.urihttps://doi.org/10.1371/journal.pone.0045138
dc.rightsAttribution 3.0 Unported*
dc.rights.urihttp://creativecommons.org/licenses/by/3.0/*
dc.titleCan diversifying selection be distinguished from history in geographic clines? A population genomic study of killifish (Fundulus heteroclitus)en_US
dc.typeArticleen_US
dc.identifier.doi10.1371/journal.pone.0045138


Files in this item

Thumbnail
Thumbnail

This item appears in the following Collection(s)

Show simple item record

Attribution 3.0 Unported
Except where otherwise noted, this item's license is described as Attribution 3.0 Unported