A polygenic architecture with habitat-dependent effects underlies ecological differentiation in Silene
Gramlich, Susanne et al. (2022), A polygenic architecture with habitat-dependent effects underlies ecological differentiation in Silene, Dryad, Dataset, https://doi.org/10.5061/dryad.4tmpg4fcn
Ecological differentiation can drive speciation but it is unclear how the genetic architecture of habitat-dependent fitness contributes to lineage divergence. We investigated the genetic architecture of cumulative flowering, a fitness component, in second-generation hybrids between Silene dioica and S. latifolia transplanted into the natural habitat of each species.
We used reduced-representation sequencing and Bayesian Sparse Linear Mixed Models (BSLMMs) to analyze the genetic control of cumulative flowering in each habitat.
Our results point to a polygenic architecture of cumulative flowering. Allelic effects were mostly beneficial or deleterious in one habitat and neutral in the other. Positive-effect alleles were often derived from the native species, whereas negative-effect alleles, at other loci, tended to originate from the non-native species.
We conclude that ecological differentiation is governed and maintained by many loci with small, habitat-dependent effects consistent with conditional neutrality. This pattern may result from differences in selection targets in the two habitats and from environmentally-dependent deleterious load. Our results further suggest that selection for native alleles and against non-native alleles acts as a barrier to gene flow between species.
see README file
see README file
Vetenskapsrådet, Award: 2012-03622
Carl Tryggers stiftelse, Award: CTS 17:249
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Award: 3100A-118221
Deutsche Forschungsgemeinschaft, Award: FA1117/1-2