title: Spatiotemporal evolution of Calophaca (fabaceae) reveals multiple dispersals in central Asian mountains.
abstract: BACKGROUND
  The Central Asian flora plays a significant role in Eurasia and the Northern Hemisphere. Calophaca, a member of this flora, includes eight currently recognized species, and is centered in Central Asia, with some taxa extending into adjacent areas. A phylogenetic analysis of the genus utilizing nuclear ribosomal ITS and plastid trnS-trnG and rbcL sequences was carried out in order to confirm its taxonomic status and reconstruct its evolutionary history.
  
  
  RESULTS
  We employed BEAST Bayesian inference for dating, and S-DIVA and BBM for ancestral area reconstruction, to study its spatiotemporal evolution. Our results show that Calophacais monophyletic and nested within Caragana. The divergence time of Calophaca is estimated at ca. 8.0 Ma, most likely driven by global cooling and aridification, influenced by rapid uplift of the Qinghai Tibet Plateau margins.
  
  
  CONCLUSIONS
  According to ancestral area reconstructions, the genus most likely originated in the Pamir Mountains, a global biodiversity hotspot and hypothesized Tertiary refugium of many Central Asian plant lineages. Dispersals from this location are inferred to the western Tianshan Mountains, then northward to the Tarbagatai Range, eastward to East Asia, and westward to the Caucasus, Russia, and Europe. The spatiotemporal evolution of Calophaca provides a case contributing to an understanding of the flora and biodiversity of the Central Asian mountains and adjacent regions.
authors: Key Laboratory of Biogeography and Bioresource in Arid Land, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China; Institute of Botany, Chinese Academy of Sciences, Beijing, China.
authors: Ming-Li
authors: ML
authors: Zhang
authors: Key Laboratory of Biogeography and Bioresource in Arid Land, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.
authors: Zhi-Bin
authors: ZB
authors: Wen
authors: Department of Botany, California Academy of Sciences, Golden Gate Park, San Francisco, California, United States of America.
authors: Peter W
authors: PW
authors: Fritsch
authors: Shrub Sciences Laboratory, Intermountain Research Station, Forest Service, U.S. Department of Agriculture, Provo, Utah, United States of America.
authors: Stewart C
authors: SC
authors: Sanderson
mesh_terms: D001208:Asia; D001499:Bayes Theorem; D044822:Biodiversity; D018742:DNA, Chloroplast / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D019143:Evolution, Molecular; D007887:Fabaceae / Q000235:genetics*; D017343:Genes, Plant; D010802:Phylogeny; D058974:Phylogeography; D018087:Plastids / Q000235:genetics; D017422:Sequence Analysis, DNA / Q000379:methods
chemical_list: D018742:DNA, Chloroplast; D018744:DNA, Plant