title: Phylogeography of Cephalotaxus oliveri (Cephalotaxaceae) in relation to habitat heterogeneity, physical barriers and the uplift of the Yungui Plateau.
abstract: Habitat heterogeneity, physical barriers, and the uplift of the Yungui Plateau were found to deeply affect the phylogeographic pattern and evolutionary history of Cephalotaxus oliveri, a perennial conifer endemic to China. In this study, we explored the phylogeography using three chloroplast sequences (trnL-trnF, trnT-trnD and atpB-rbcL) in 22 natural populations of C. oliveri distributed throughout its range. The Yungui Plateau populations of C. oliveri were revealed to origin ca. 9.15Ma by molecular clock estimation, which is consistent with rapid uplift of the Qinghai-Tibetan Plateau (QTP) ca. 8-10Ma. Additionally, geological effects of the Yungui Plateau were suggested to promote the rapid intra-specific differentiation of C. oliveri in the Pliocene and Early Pleistocene. The relatively low level of genetic diversity (h=0.719, θ=1.17×10(-3)) and high population differentiation (NST=0.771 and GST=0.642) implied restricted gene flow among populations, which was confirmed by the Nested Clade Analysis (NCA). Mismatch distribution and haplotypes network provided evidences of recent demographic population expansion. Furthermore, the statistical dispersal-vicariance analysis indicated that the center of origin was in Central China. The comparison of haplotype distribution patterns indicated that the regions of HNHPS and HBLD were the potential refugia during the Pleistocene ice ages. Our results highlighted that habitat heterogeneity and physical barriers presenting in a species range can predict genetic patterns.
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: C B
authors.initials: CB
authors.lastname: Wang
authors.affiliation: College of Life Science, South China Agricultural University, Guangzhou 510642, China. Electronic address: ting_wang@yahoo.com.
authors.forename: T
authors.initials: T
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China; Research Institute of Sun Yat-sen University in Shenzhen, Shenzhen 518057, China; State Key Laboratory of Biocontrol Shenzhen R&D Center, Shenzhen 518057, China; Institute for Technology Research and Innovation of Sun Yat-sen University, Zhuhai 519000, China. Electronic address: suyj@mail.sysu.edu.cn.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Su
mesh_terms: D001483:Base Sequence; D032483:Cephalotaxus / Q000145:classification* / Q000235:genetics; D002681:China; D018742:DNA, Chloroplast / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D017753:Ecosystem; D051456:Gene Flow; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes; D008957:Models, Genetic; D010802:Phylogeny; D058974:Phylogeography; D017422:Sequence Analysis, DNA
chemical_list: D018742:DNA, Chloroplast; D018744:DNA, Plant
keywords: Cephalotaxus oliveri; Geological effect; Habitat heterogeneity; Phylogeography; Physical barrier; Yungui Plateau