The uplift of the Qinghai-Tibet Plateau and glacial oscillations triggered the diversification of (Galliformes, Phasianidae).

The Qinghai-Tibet Plateau (QTP) plays an important role in avian diversification. To reveal the relationship between the QTP uplift and avian diversification since the Late Cenozoic, here, we analyzed the phylogenetic relationship and biogeographical pattern of the genus (Galliformes, Phasianidae) and the probable factors of speciation in the period of the QTP uplift inferred from concatenated data of four nuclear and five mitochondrial genes using the method of the Bayesian inference. Phylogenetic analysis indicated that had a close relationship with and conflicted with the previous taxonomy of dark-bellied and white-bellied groups. The molecular clock showed that the speciation of was profoundly affected by the uplift of the QTP and glacial oscillations. Biogeographic analysis suggested that the extant snowcocks originated from the QTP, and the QTP uplift and glacial oscillations triggered the diversification of ancestor. Specifically, the uplift of the mountain provided a prerequisite for the colonization of snowcocks as a result of the collision between the Indian and the Arab plates and the Eurasian plate, in which ecological isolation (the glacial and interglacial periods alternate) and geographical barrier had accelerated the diversification process. Interestingly, we discovered hybrids between and for the first time and suggested that and hybridized after a second contact during the glacial period. Here, we proposed that the hybrid offspring was the ancestor of the . In conclusion, the uplift of QTP and glacial oscillations triggered the snowcocks colonization, and then, isolation and introgression hybridization promoted diversification.