AUTHOR=Rešetnik Ivana , Záveská Eliška , Grgurev Marin , Bogdanović Sandro , Bartolić Paolo , Frajman Božo 

TITLE=Stability in the South, Turbulence Toward the North: Evolutionary History of Aurinia saxatilis (Brassicaceae) Revealed by Phylogenomic and Climatic Modelling Data

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.822331

DOI=10.3389/fpls.2022.822331

ISSN=1664-462X

ABSTRACT=The Balkan Peninsula played an important role in the evolution of many Mediterranean plants and served as a major source for the post-Pleistocene colonisation of central and northern Europe. Its complex geo-climatic history and environmental heterogeneity significantly influenced spatiotemporal diversification and resulted in intricate phylogeographic patterns. To explore the evolutionary dynamics and phylogeographic patterns within a widespread eastern Mediterranean and central European Aurinia saxatilis, we used a combination of phylogenomic (restriction-site associated DNA sequencing - RADseq) and phylogenetic (sequences of the plastid marker ndhF) data as well as species distribution models generated for the present and the Last Glacial Maximum (LGM). The inferred phylogenies retrieved three main geographically distinct lineages. The southern lineage is restricted to the eastern Mediterranean, distributed throughout the Aegean area, southern Balkan Peninsula and southern Apennine Peninsula, and corresponds to the species main distribution area during the LGM. The eastern lineage extends from the eastern Balkan Peninsula over the Carpathians towards central Europe, while the central lineage occupies the central Balkan Peninsula. Molecular dating places diversification of all three lineages in early to middle Pleistocene, indicating their long term independent evolutionary trajectories. Our data revealed an early divergence and stable in situ persistence of the southernmost, eastern Mediterranean lineage, whereas the mainland, south-east European lineages experienced more complex and turbulent evolutionary dynamics triggered by Pleistocene climatic oscillations. Our data also support the existence of multiple glacial refugia in south-east Europe and highlight the central Balkan Peninsula not only as a cradle of lineage diversifications, but also as a cradle of lineage dispersals. Finally, the extant genetic variation within A. saxatilis is congruent with the taxonomic separation of peripatric A. saxatilis subsp. saxatilis and A. saxatilis subsp. orientalis, whereas the taxonomic value of A. saxatilis subsp. megalocarpa remains doubtful.