Population genomics and speciation
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The process of speciation begins with genomically-localised barriers to gene exchange associated with loci for local adaptation, intrinsic incompatibility or assortative mating. The barrier then spreads until reproductive isolation influences the whole genome. The population genomics approach can be used to identify regions of reduced gene flow by detecting loci with greater differentiation than expected from the average across many loci. Recently, this approach has been used in several systems. I review these studies, concentrating on the robustness of the approach and the methods available to go beyond the simple identification of differentiated markers. Population genomics has already contributed significantly to understanding the balance between gene flow and selection during the evolution of reproductive isolation and has great future potential both in genome species and in non-model organisms.
KeywordsFST Genome scan Reproductive isolation Local adaptation
I am very grateful to Jacob Hoglund and Gernot Segelbacher for organising, and inviting me to attend, the very stimulating workshop from which these proceedings are derived. The workshop was funded by the European Science Foundation. Discussions with Juan Galindo about population genomics approaches have been important in the development of this paper. My work on Littorina is in collaboration with John Grahame and has been funded by the BBSRC.
- Coyne JA, Orr HA (2004) Speciation. Sinauer Associates, SunderlandGoogle Scholar
- Egan SR, Nosil P, Funk DJ (2008) Selection and genomic differentiation during ecological speciation: isolating the contributions of host-association via a comparative genome scan of Neochlamisus bebbianae leaf beetles. Evolution (online early)Google Scholar
- Minder AM, Widmer A (2008) A population genomic analysis of species boundaries: neutral processes, adaptive divergence and introgression between two hybridizing plant species. Mol Ecol (online early)Google Scholar
- Pool JE, DuMont VB, Mueller JL, Aquadro CF (2006) A scan of molecular variation leads to the narrow localization of a selective sweep affecting both afrotropical and cosmopolitan populations of Drosophila melanogaster. Genetics 172:1093–1105. doi: 10.1534/genetics.105.049973 CrossRefPubMedGoogle Scholar
- Price T (2007) Speciation in birds. Roberts and Company, Greenwood VillageGoogle Scholar
- Singleton DR (2008) Evaluating the reliability of FST-based methods at detecting the signature of selection in microsatellite markers linked to a selection-targeted locus. Ph.D. thesis, University of ReadingGoogle Scholar
- Smadja C, Galindo J, Butlin RK (2008) Hitching a lift on the road to speciation. Mol Ecol (in press)Google Scholar
- Vasemagi A, Nilsson J, Primmer CR (2005) Expressed sequence tag-linked microsatellites as a source of gene-associated polymorphisms for detecting signatures of divergent selection in Atlantic salmon (Salmo salar L.). Mol Biol Evol 22:1067–1076. doi: 10.1093/molbev/msi093 CrossRefPubMedGoogle Scholar
- Vekemans X, Beauwens T, Lemaire M, Roldan-Ruiz I (2002) Data from amplified fragment length polymorphism (AFLP) markers show indication of size homoplasy and of a relationship between degree of homoplasy and fragment size. Mol Ecol 11:139–151. doi: 10.1046/j.0962-1083.2001.01415.x CrossRefPubMedGoogle Scholar
- Via S, West J (2008) The genetic mosaic suggests a new role for hitchhiking in ecological speciation. Mol Ecol (in press)Google Scholar