Format: ORAL

Juan Manuel Gorospe1, Tom Fr1, Jaromr Kucera2, Ali Dnmez3, Sirri Yzbasioglu4, Zbeyde Ugurlu Aydin3, Roswitha Elisabeth Schmickl1,5 and Marek Slovk1,2

1 Department of Botany, Charles University, Benátská 2, 128 01 Praha, Czech Republic 2 Institute of Botany, Plant Sciences and Biodiversity Centre, Slovak Academy of Sciences, Dúbravská cesta 9, 845 23 Bratislava, Slovakia 3 Botany Section, Department of Biology, Faculty of Science, Hacettepe University, 06800 Beytepe-Ankaraz, Turkey 4 Department of Botany, Faculty of Science, Istanbul University, Vezneciler, Istanbul, Türkiye 5 Institute of Botany of the Czech Academy of Sciences, Zámek 1, 252 43 Pruhonice, Czech Republic

The Mediterranean basin emerges as a biodiversity hotspot, housing an exceptionally high number of endemic entities. This biodiversity stems primarily from the regions long-term climatic stability, coupled with extreme geomorphological heterogeneity, including myriad island systems and high mountain ranges with diverse bedrock. Despite climatic stability, oscillations during the Pleistocene triggered contractions and expansions in the majority of organisms. These fluctuations led to recurrent contact between previously allopatric lineages or species, fostering both within and between species hybridization and introgression. The resultant extensive and recurring gene flow significantly contributed to the evolution of numerous hybridogenous lineages and speciation events. This study delves into the evolutionary history of the genus Picris L. (Compositae), serving as an exemplary model to investigate the impact of hybridization on the diversification and speciation processes. The genus Picris originated in the Mediterranean, featuring two major lineagesone evolving in Northern Africa and the other arising in the eastern Mediterranean, specifically in the southern region of Asia Minor and the Near East. Both regions host the highest diversity of the genus, with pronounced species diversity, particularly in the latter region. Previous studies suggested that, beyond allopatric speciation, hybridization and introgression likely play a significant role in this eastern Mediterranean lineage. Employing target enrichment with genome skimming (Hyb-Seq) and inferring both nuclear and plastome phylogenies, our investigation scrutinized the extent to which gene flow contributed to endemic diversity in the genus Picris in this region. Our findings indicate that secondary contacts and gene flow between species and their lineages occurred recurrently across several time horizons. The evolution of many endemics, particularly those from Asia Minor, was notably influenced by hybridization and introgression events.