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Explaining how plants from eastern Asia migrated to other Northern Hemisphere regions is still challenging. The genus Sorbus sensu stricto (including c . 88 species) is considered as a good example to illuminate this scenario, due to the wide distribution in the temperate zone and high diversity in the Himalayas and Hengduan Mountains. Based on four nuclear markers ( LEAFY -2, GBSSI -1, SBEI and WD ) and one chloroplast marker ( rps16 - trnK ), we reconstructed the phylogenetic relationship of Sorbus using 54 taxa (60% of the genus representing all subgenera, sections, or series and geographical areas in the previous classifications), and estimated divergence time and historical biogeography of the genus. Phylogenetic analyses supported that the subgenera Sorbus and Albo - carmesinae , as defined by traditional morphological characters (such as fruit color), are suitable. However, five clades defined by phylogenetic analysis of the genus are not consistent with traditionally defined sections or series. Molecular dating and biogeographic reconstruction showed that the age of the most recent common ancestor was estimated at 41 mya (95% HPD: 49–35 mya) in eastern Asia. Four dispersal events are assumed to explain the wide distribution of Sorbus in the temperate zone and diversification in the edges of Qinghai-Tibet Plateau (QTP). Species dispersed from eastern Asia to the Tianshan Mountains, North America and Europe during the Oligocene and Miocene period. We found that polyploidization occurred multiple times in the subgenus Albo - carmesinae , in the Tianshan Mountains, Himalayas, and H-D Mountains. Finally, we suggest that apomixis, polyploidization, and hybridization may have combined with the multistage uplifting of Himalayas and H-D Mountains (and the subsequent increases in geologic, ecological and climatic heterogeneity) to drive the striking species diversity of Sorbus in this region. [ABSTRACT FROM AUTHOR]

Background and Aims The East Asian–Tethyan disjunction pattern and its mechanisms of formation have long been of interest to researchers. Here, we studied the biogeographical history of Asteraceae tribe Cardueae, with a particular focus on the temperate East Asian genus Atractylodes DC. to understand the role of tectonic and climatic events in driving the diversification and disjunctions of the genus. Methods A total of 76 samples of Atractylodes from 36 locations were collected for RAD-sequencing. Three single nucleotide polymorphism (SNP) datasets based on different filtering strategies were used for phylogenetic analyses. Molecular dating and ancestral distribution reconstruction were performed using both chloroplast DNA sequences (127 Cardueae samples) and SNP (36 Atractylodes samples) datasets. Key Results Six species of Atractylodes were well resolved as individually monophyletic, although some introgression was identified among accessions of A. chinensis , A. lancea and A. koreana. Dispersal of the subtribe Carlininae from the Mediterranean to East Asia occurred after divergence between Atractylodes and Carlina L. +  Atractylis L. +  Thevenotia DC. at ~31.57 Ma, resulting in an East Asian–Tethyan disjunction. Diversification of Atractylodes in East Asia mainly occurred from the Late Miocene to the Early Pleistocene. Conclusions Aridification of Asia and the closure of the Turgai Strait in the Late Oligocene promoted the dispersal of Cardueae from the Mediterranean to East China. Subsequent uplift of the Qinghai–Tibet Plateau as well as changes in Asian monsoon systems resulted in an East Asian–Tethyan disjunction between Atractylodes and Carlina  +  Atractylis  +  Thevenotia. In addition, Late Miocene to Quaternary climates and sea level fluctuations played major roles in the diversification of Atractylodes. Through this study of different taxonomic levels using genomic data, we have revealed an overlooked dispersal route between the Mediterranean and far East Asia (Japan/Korea) via Central Asia and East China. [ABSTRACT FROM AUTHOR]