Specific ecological conditions in the high mountain environment exert a selective pressure that often leads to convergent trait evolution. Reticulations induced by incomplete lineage sorting and introgression can lead to discordant trait patterns among gene and species trees (hemiplasy/xenoplasy), providing a false illusion that the traits under study are homoplastic. Using phylogenetic species networks, we explored the effect of gene exchange on trait evolution in Soldanella, a genus profoundly influenced by historical introgression. At least three features evolved independently multiple times: the single-flowered dwarf phenotype, dysploid cytotype, and ecological generalism. The present analyses also indicated that the recurring occurrence of stoloniferous growth might have been prompted by an introgression event between an ancestral lineage and a still extant species, although its emergence via convergent evolution cannot be completely ruled out. Phylogenetic regression suggested that the independent evolution of larger genomes in snowbells is most likely a result of the interplay between hybridization events of dysploid and euploid taxa and hostile environments at the range margins of the genus. The emergence of key intrinsic and extrinsic traits in snowbells has been significantly impacted not only by convergent evolution but also by historical and recent introgression events.

Department of Botany and Biodiversity Research University of Vienna Rennweg 14 1030 Vienna Austria

Department of Botany Charles University Benátská 2 128 01 Prague Czech Republic

Department of Phytology Faculty of Forestry Technical University Zvolen Masarykova 24 960 53 Zvolen Slovak Republic

Department of Zoology Comenius University Bratislava Ilkovičova 6 842 15 Bratislava Slovak Republic

Institute of Botany Plant Science and Biodiversity Centre Slovak Academy of Sciences Dúbravská cesta 9 845 23 Bratislava Slovak Republic

Slovak National Museum Natural History Museum Vajanského nábrežie 2 810 06 Bratislava Slovak Republic

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Bridging micro and macroevolution: insights from chromosomal dynamics in plants