Data from: The genomic bases of morphological divergence and reproductive isolation driven by ecological speciation in Senecio (Asteraceae)
Chapman, Mark A, University of Southampton
Hiscock, Simon J, University of Oxford
Filatov, Dmitry A, University of Oxford
Published Jun 01, 2016 on Dryad.
Cite this dataset
Chapman, Mark A; Hiscock, Simon J; Filatov, Dmitry A (2016). Data from: The genomic bases of morphological divergence and reproductive isolation driven by ecological speciation in Senecio (Asteraceae) [Dataset]. Dryad. https://doi.org/10.5061/dryad.gb6g6
Ecological speciation, driven by adaptation to contrasting environments, provides an attractive opportunity to study the formation of distinct species, and the role of selection and genomic divergence in this process. Here, we focus on a particularly clear-cut case of ecological speciation to reveal the genomic bases of reproductive isolation and morphological differences between closely related Senecio species, whose recent divergence within the last ~200,000 years was likely driven by the uplift of Mt. Etna (Sicily). These species form a hybrid zone, yet remain morphologically and ecologically distinct, despite active gene exchange. Here, we report a high-density genetic map of the Senecio genome and map hybrid breakdown to one large and several small quantitative trait loci (QTL). Loci under diversifying selection cluster in three 5 cM regions which are characterized by a significant increase in relative (F(ST)), but not absolute (d(XY)), interspecific differentiation. They also correspond to some of the regions of greatest marker density, possibly corresponding to 'cold-spots' of recombination, such as centromeres or chromosomal inversions. Morphological QTL for leaf and floral traits overlap these clusters. We also detected three genomic regions with significant transmission ratio distortion (TRD), possibly indicating accumulation of intrinsic genetic incompatibilities between these recently diverged species. One of the TRD regions overlapped with a cluster of high species differentiation, and another overlaps the large QTL for hybrid breakdown, indicating that divergence of these species may have occurred due to a complex interplay of ecological divergence and accumulation of intrinsic genetic incompatibilities.
F2 genotypes for linkage mapping
Raw genotypes for 966 markers (obtained from RNA-seq data) for 64 F2 individuals from a cross between Senecio aethnensis and S. chrysanthemifolius