Data from: Quantitative genetic inheritance of morphological divergence in a lake-stream stickleback ecotype pair: implications for reproductive isolation

Ecological selection against hybrids between populations occupying different habitats might be an important component of reproductive isolation during the initial stages of speciation. The strength and directionality of this barrier to gene flow depends on the genetic architecture underlying divergence in ecologically relevant phenotypes. We here present line cross analyses of inheritance for two key foraging-related morphological traits involved in adaptive divergence between stickleback ecotypes residing parapatrically in lake and stream habitats within the Misty Lake watershed (Vancouver Island, Canada). One main finding is striking genetic dominance of the lake phenotype for body depth. Selection associated with this phenotype against first and later generation hybrids should therefore be asymmetric, hindering introgression from the lake to the stream population but not vice versa. Another main finding is that divergence in gill raker number is inherited additively and should therefore contribute symmetrically to reproductive isolation. Our study suggests that traits involved in adaptation might contribute to reproductive isolation qualitatively differently, depending on their mode of inheritance.Individual landmarks Berner et al. 2011see "ReadMe Berner et al. 2011.txt"SexByFamilyConsensus landmarks Berner et al. 2011see "ReadMe Berner et al. 2011.txt"Individual data Berner et al. 2011see "ReadMe Berner et al. 2011.txt"SexByFamily data Berner et al. 2011see "ReadMe Berner et al. 2011.txt"ReadMe Berner et al. 2011ReadMe file describing all four data files