Molecular signatures of reticulate evolution within the complex of European pine taxa

Speciation mechanisms, including the role of interspecific gene flow and introgression in emergence of new species, are the major focus of evolutionary studies. Inference of taxonomic relationship between closely related species maybe challenged by past hybridization events, but at the same time it may provide new knowledge about mechanisms responsible for the maintenance of species integrity despite interspecific gene flow. Here, using nucleotide sequence variation and utilizing a coalescent modelling framework, we tested the role of hybridization and introgression in the evolutionary history of closely related pine taxa from Pinus mugo complex and P. sylvestris. We compared the patterns of polymorphism and divergence between taxa and found great overlap of neutral variation within P. mugo complex. Our phylogeny reconstruction indicated multiple instances of reticulation events in the past, suggesting an important role of interspecific gene flow in the species divergence. The best fitt...