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Model‐based demographic inference of introgression history in European whitefish species pairs'
Author(s) -
Rougeux Clément,
Gagnaire PierreAlexandre,
Bernatchez Louis
Publication year - 2019
Publication title -
journal of evolutionary biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.289
H-Index - 128
eISSN - 1420-9101
pISSN - 1010-061X
DOI - 10.1111/jeb.13482
Subject(s) - biology , allopatric speciation , parallel evolution , evolutionary biology , demographic history , lineage (genetic) , disruptive selection , vicariance , coregonus lavaretus , genetic divergence , gene flow , ecology , selection (genetic algorithm) , phylogeography , natural selection , genetic variation , genetic diversity , phylogenetics , genetics , population , gene , fish <actinopterygii> , demography , artificial intelligence , sociology , fishery , computer science
Parallel phenotypic differentiation is generally attributed to parallel adaptive divergence as an evolutionary response to similar environmental contrasts. Such parallelism may actually originate from several evolutionary scenarios ranging from repeated parallel divergence caused by divergent selection to a unique divergence event followed by gene flow. Reconstructing the evolutionary history underlying parallel phenotypic differentiation is thus fundamental to understand the relative contribution of demography and selection on genomic divergence during speciation. In this study, we investigate the divergence history of replicate European whitefish ( Coregonus lavaretus ), limnetic and benthic species pairs from two lakes in Norway and two lakes in Switzerland. Demographic models accounting for semi‐permeability and linked selection were fitted to the unfolded joint allele frequency spectrum built from genome‐wide SNP s and compared to each other in each species pair. We found strong support for a model of asymmetrical post‐glacial secondary contact between glacial lineages in all four lakes. Moreover, our results suggest that heterogeneous genomic differentiation has been shaped by the joint action of linked selection accelerating lineage sorting during allopatry, and heterogeneous migration eroding divergence at different rates along the genome following secondary contact. Our analyses reveal how the interplay between demography, selection and historical contingency has influenced the levels of diversity observed in previous whitefish phylogeographic studies. This study thus provides new insights into the historical demographic and selective processes that shaped the divergence associated with ecological speciation in European whitefish.