Genome-wide admixture and ecological niche modelling reveal the maintenance of species boundaries despite long history of interspecific gene flow
2014 (English)In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 23, no 8, 2046-2059 p.Article in journal (Refereed) Published
The maintenance of species boundaries despite interspecific gene flow has been a continuous source of interest in evolutionary biology. Many hybridizing species have porous genomes with regions impermeable to introgression, conferring reproductive barriers between species. We used ecological niche modelling to study the glacial and postglacial recolonization patterns between the widely hybridizing spruce species Picea glauca and P.engelmannii in western North America. Genome-wide estimates of admixture based on a panel of 311 candidate gene single nucleotide polymorphisms (SNP) from 290 genes were used to assess levels of admixture and introgression and to identify loci putatively involved in adaptive differences or reproductive barriers between species. Our palaeoclimatic modelling suggests that these two closely related species have a long history of hybridization and introgression, dating to at least 21000years ago, yet species integrity is maintained by a combination of strong environmental selection and reduced current interspecific gene flow. Twenty loci showed evidence of divergent selection, including six loci that were both F-st outliers and associated with climatic gradients, and fourteen loci that were either outliers or showed associations with climate. These included genes responsible for carbohydrate metabolism, signal transduction and transcription factors.
Place, publisher, year, edition, pages
2014. Vol. 23, no 8, 2046-2059 p.
ecological niche modelling, admixture, outlier loci, spruce
Biochemistry and Molecular Biology Environmental Sciences
IdentifiersURN: urn:nbn:se:umu:diva-88392DOI: 10.1111/mec.12710ISI: 000333858200013OAI: oai:DiVA.org:umu-88392DiVA: diva2:718263