title: Evolutionary origin and demographic history of an ancient conifer (Juniperus microsperma) in the Qinghai-Tibetan Plateau.
abstract: All Qinghai-Tibetan Plateau (QTP) endemic species are assumed to have originated recently, although very rare species most likely diverged early. These ancient species provide an excellent model to examine the origin and evolution of QTP endemic plants in response to the QTP uplifts and the climate changes that followed in this high altitude region. In this study, we examined these hypotheses by employing sequence variation from multiple nuclear and chloroplast DNA of 239 individuals of Juniperus microsperma and its five congeners. Both phylogenetic and population genetic analyses revealed that J. microsperma diverged from its sister clade comprising two species with long isolation around the Early Miocene, which corresponds to early QTP uplift. Demographic modeling and coalescent tests suggest that J. microsperma experienced an obvious bottleneck event during the Quaternary when the global climate greatly oscillated. The results presented here support the hypotheses that the QTP uplifts and Quaternary climate changes played important roles in shaping the evolutionary history of this rare juniper.
authors.affiliation: State Key Laboratory of Grassland Agro-Ecosystem, School of Life Sciences, Lanzhou University, Lanzhou 730000, Gansu, China.
authors.forename: Hui-Ying
authors.initials: HY
authors.lastname: Shang
authors.affiliation: Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an 710069, Shaanxi, China.
authors.forename: Zhong-Hu
authors.initials: ZH
authors.lastname: Li
authors.affiliation: State Key Laboratory of Grassland Agro-Ecosystem, School of Life Sciences, Lanzhou University, Lanzhou 730000, Gansu, China.
authors.forename: Miao
authors.initials: M
authors.lastname: Dong
authors.affiliation: Biology Department, Baylor University, Box 97388, Waco, TX 76798, USA.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Adams
authors.affiliation: Faculty of Biology and Geology, University of Marburg, 35032 Marburg, Germany.
authors.forename: Georg
authors.initials: G
authors.lastname: Miehe
authors.affiliation: Faculty of Biology and Geology, University of Marburg, 35032 Marburg, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Opgenoorth
authors.affiliation: 1] State Key Laboratory of Grassland Agro-Ecosystem, School of Life Sciences, Lanzhou University, Lanzhou 730000, Gansu, China [2] Key Laboratory for Bio-resources and Eco-environment, Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, Sichuan, China.
authors.forename: Kang-Shan
authors.initials: KS
authors.lastname: Mao
mesh_terms: D005075:Biological Evolution; D002736:Chloroplasts / Q000235:genetics*; D018742:DNA, Chloroplast / Q000235:genetics*; D018744:DNA, Plant / Q000235:genetics*; D014644:Genetic Variation; D005828:Genetics, Population; D005843:Geography; D018653:Juniperus / Q000235:genetics*; D010802:Phylogeny; D018609:Tibet
chemical_list: D018742:DNA, Chloroplast; D018744:DNA, Plant