title: Multilocus Analyses Reveal Postglacial Demographic Shrinkage of Juniperus morrisonicola (Cupressaceae), a Dominant Alpine Species in Taiwan.
abstract: Postglacial climate changes alter geographical distributions and diversity of species. Such ongoing changes often force species to migrate along the latitude/altitude. Altitudinal gradients represent assemblage of environmental, especially climatic, variable factors that influence the plant distributions. Global warming that triggered upward migrations has therefore impacted the alpine plants on an island. In this study, we examined the genetic structure of Juniperus morrisonicola, a dominant alpine species in Taiwan, and inferred historical, demographic dynamics based on multilocus analyses. Lower levels of genetic diversity in north indicated that populations at higher latitudes were vulnerable to climate change, possibly related to historical alpine glaciers. Neither organellar DNA nor nuclear genes displayed geographical subdivisions, indicating that populations were likely interconnected before migrating upward to isolated mountain peaks, providing low possibilities of seed/pollen dispersal across mountain ranges. Bayesian skyline plots suggested steady population growth of J. morrisonicola followed by recent demographic contraction. In contrast, most lower-elevation plants experienced recent demographic expansion as a result of global warming. The endemic alpine conifer may have experienced dramatic climate changes over the alternation of glacial and interglacial periods, as indicated by a trend showing decreasing genetic diversity with the altitudinal gradient, plus a fact of upward migration.
authors: Kinmen National Park, Kinmen, Taiwan.
authors: Chi-Chun
authors: CC
authors: Huang
authors: Endemic Species Research Institute, Nantou, Taiwan.
authors: Tsai-Wen
authors: TW
authors: Hsu
authors: Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan.
authors: Hao-Ven
authors: HV
authors: Wang
authors: Institute of Tropical Plant Sciences, National Cheng Kung University, Tainan, Taiwan.
authors: Zin-Huang
authors: ZH
authors: Liu
authors: Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan.
authors: Yi-Yen
authors: YY
authors: Chen
authors: Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan.
authors: Chi-Te
authors: CT
authors: Chiu
authors: Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan.
authors: Chao-Li
authors: CL
authors: Huang
authors: Graduate Institute of Bioresources, National Pingtung University of Science and Technology, Pingtung, Taiwan.
authors: Kuo-Hsiang
authors: KH
authors: Hung
authors: Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan.|University Center for Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan.
authors: Tzen-Yuh
authors: TY
authors: Chiang
mesh_terms: D000531:Altitude; D044822:Biodiversity; D018533:Biomass; D056426:Genetic Loci; D014644:Genetic Variation; D057232:Global Warming; D018653:Juniperus / Q000235:genetics*; D013624:Taiwan