Insight into the roles of selection in speciation from genomic patterns of divergence and introgression in secondary contact in venomous rattlesnakes Journal Article uri icon

Overview

abstract

  • AbstractInvestigating secondary contact of historically isolated lineages can provide insight into how selection and drift influence genomic divergence and admixture. Here, we studied the genomic landscape of divergence and introgression following secondary contact between lineages of the Western Diamondback Rattlesnake (Crotalus atrox) to determine whether genomic regions under selection in allopatry also contribute to reproductive isolation during introgression. We used thousands of nuclear loci to study genomic differentiation between two lineages that have experienced recent secondary contact following isolation, and incorporated sampling from a zone of secondary contact to identify loci that are resistant to gene flow in hybrids. Comparisons of patterns of divergence and introgression revealed a positive relationship between allelic differentiation and resistance to introgression across the genome, and greater‐than‐expected overlap between genes linked to lineage‐specific divergence and loci that resist introgression. Genes linked to putatively selected markers were related to prominent aspects of rattlesnake biology that differ between populations of Western Diamondback rattlesnakes (i.e., venom and reproductive phenotypes). We also found evidence for selection against introgression of genes that may contribute to cytonuclear incompatibility, consistent with previously observed biased patterns of nuclear and mitochondrial alleles suggestive of partial reproductive isolation due to cytonuclear incompatibilities. Our results provide a genome‐scale perspective on the relationships between divergence and introgression in secondary contact that is relevant for understanding the roles of selection in maintaining partial isolation of lineages, causing admixing lineages to not completely homogenize.

publication date

  • June 1, 2017

has restriction

  • gold

Date in CU Experts

  • January 4, 2024 12:32 PM

Full Author List

  • Schield DR; Adams RH; Card DC; Perry BW; Pasquesi GM; Jezkova T; Portik DM; Andrew AL; Spencer CL; Sanchez EE

author count

  • 13

Other Profiles

International Standard Serial Number (ISSN)

  • 2045-7758

Electronic International Standard Serial Number (EISSN)

  • 2045-7758

Additional Document Info

start page

  • 3951

end page

  • 3966

volume

  • 7

issue

  • 11