Phylogeography And Adaptive Evolution Of Niviventer Confucianus

In Quaternary Period,the global climate change has a great effect on the growth and evolution of the existing species,their geographical distribution,as well as population genetic structure.In recent years,the emergence and development of phylogeography have provided an effective way to conjecture the shelter of the existing species in Quaternary glaciation.In this study,Niviventer confucianus,widely distributed in China,as the research object,to explore the diffusion route in the glacial refugium during the ice age and thus provide a theoretic basis for the study of the various groups in evolution process,but also provide a theoretical basis for the protection of biodiversity.In addition,we also explored whether temperature and related indices,like latitude and elevation,produced adaptive evolution of the mitochondrial genes under selective stress.This study first through the mitochondrial Cyt b gene of 243 specimem of N.confucianus complex,from 17 Provinces,in China for identification and analyzes its phylogeny and historical dynamics.At the end,the mitochondrial Cyt b,ATP6 and ATP8 gene were selected to analyze the pressure analysis,exploration whether adaptive evolution occurs.The main conclusions are as follows:(1)By molecular method,the population distribution range of N.confucianus is obviously smaller than that of traditional understanding.In China,the main distribution areas should be Yunnan,Sichuan and the north of the Yangtze river.There are some cryptic species of N.confucianus complex in Guangxi,Shandong,Xizang and Yunnan.(2)The divergence is mainly due to agency in the Qinghai-Tibet Plateau uplift caused by climate change,especially during the glacial multiple convolution kunhuang movement after the ice and lead to widespread social withdrawal and the expansion of rat populations repeatedly,generating a plurality of geographic isolation structure by geography,but in the distribution area of each lineage on the geographical relationship still overlap.(3)During the glacial period,there were many shelters in the South and North of the community,but there were still a few channels between the shelters to communicate with each other.After the last glacial period,as the climate warmed up,the northern climate was dry,and the N.confucianus distributed in the North of China expanded to the northeast and south along the Yangtze river.Populations in the middle of Sichuan spread eastward.(4)In the selection pressure analysis,the selection of N.confucianus was mainly influenced by the purifying selection.Mitochondrial Cyt b and ATPase showed no corresponding trend in temperature,latitude and elevation.Confirmed by this study,based on the traditional morphological identification for N.confucianus were complex,and according to the conclusion of the latest research of molecular phylogenetic analysis,distributed in the region south of the Yangtze River form together as a monophyletic group of N.lotipes.The evolution of N.confucianus is attributed to the uplift of the Qinghai-Tibet Plateau and the multiple events of the ice age,resulting in a strong change in the climate in China,and its lineage divergence in the respective distribution areas.The widely distributed of N.confucianus adapt to the environment of their respective distribution areas,and have different molecular adaptation mechanisms to the adaptive evolution of plateau indigenous animals.