Phylogeny and genetic diversity reveal the influence of Qinghai-Tibet Plateau uplift on the divergence and distribution of Gymnocypris species

The complex environments and climatic conditions of the Qinghai-Tibet Plateau (QTP) create unique patterns of species diversity. However, the effect of uplift of the QTP on the distribution of Gymnocypris species (Gymnocypris) remain unclear. We found that the Qilian Mountain (QL) population has the highest genetic diversity by mitochondrial DNA hypervariable region of Gymnocypris species, the Tibetan (T) population has the lowest genetic diversity. The T population differs significantly from the Qinghai Lake (QH) and QL populations based on single nucleotide polymorphisms. A phylogeny and network distribution of this species on the QTP reveal differences in its genetic structure and support its taxonomic status. Neutrality tests reveal that Gymnocypris species has experienced different degrees of expansion, even secondary expansion. A divergence timetree estimates that the time of separation of different populations is possible related to uplift of the QTP and is consistent with the time of corresponding geological events. The QL population was separated from the other populations during the third uplift of the QTP (approximately 0.14 million years ago), and the QH and T populations were separated in the late Pleistocene to the Holocene (approximately 0.03 million years ago). In conclusion, this study provides different insights into the distribution of Gymnocypris species due to uplift of the QTP. Gymnocypris species was separated into different populations by this uplift, and each population exhibits unique characteristics, especially in terms of genetic structure and the degree of expansion. Moreover, the divergence time is consistent with the time of uplift of the QTP.