title: Molecular Biogeography of Tribe Thermopsideae (Leguminosae): A Madrean-Tethyan Disjunction Pattern with an African Origin of Core Genistoides.
abstract: Thermopsideae has 45 species and exhibits a series of interesting biogeographical distribution patterns, such as Madrean-Tethyan disjunction and East Asia-North America disjunction, with a center of endemism in the Qinghai-Xizang Plateau (QTP) and Central Asia. Phylogenetic analysis in this paper employed maximum likelihood using ITS, rps16, psbA-trnH, and trnL-F sequence data; biogeographical approaches included BEAST molecular dating and Bayesian dispersal and vicariance analysis (S-DIVA). The results indicate that the core genistoides most likely originated in Africa during the Eocene to Oligocene, ca. 55-30 Ma, and dispersed eastward to Central Asia at ca. 33.47 Ma. The origin of Thermopsideae is inferred as Central Asian and dated to ca. 28.81 Ma. Ammopiptanthus is revealed to be a relic. Birth of the ancestor of Thermopsideae coincided with shrinkage of the Paratethys Sea at ca. 30 Ma in the Oligocene. The Himalayan motion of QTP uplift of ca. 20 Ma most likely drove the diversification between Central Asia and North America. Divergences in East Asia, Central Asia, the Mediterranean, and so forth, within Eurasia, except for Ammopiptanthus, are shown to be dispersals from the QTP. The onset of adaptive radiation at the center of the tribe, with diversification of most species in Thermopsis and Piptanthus at ca. 4-0.85 Ma in Tibet and adjacent regions, seems to have resulted from intense northern QTP uplift during the latter Miocene to Pleistocene.
authors.affiliation: Key Laboratory of Biogeography and Bioresource in Arid Land, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, Xinjiang 830011, China ; Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Ming-Li
authors.initials: ML
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Biogeography and Bioresource in Arid Land, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, Xinjiang 830011, China ; Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.
authors.forename: Jian-Feng
authors.initials: JF
authors.lastname: Huang
authors.affiliation: Shrub Sciences Laboratory, Intermountain Research Station, Forest Service, U.S. Department of Agriculture, UT 84601, USA.
authors.forename: Stewart C
authors.initials: SC
authors.lastname: Sanderson
authors.affiliation: School of Life Science, Shihezi University, Shihezi, Xinjiang 832003, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Yan
authors.affiliation: Northwest Plateau Institute of Biology, Chinese Academy of Sciences, Xining, Qinghai 810001, China.
authors.forename: Yu-Hu
authors.initials: YH
authors.lastname: Wu
authors.affiliation: Key Laboratory of Biogeography and Bioresource in Arid Land, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, Xinjiang 830011, China.
authors.forename: Bo-Rong
authors.initials: BR
authors.lastname: Pan
mesh_terms: D000349:Africa; D001208:Asia; D001499:Bayes Theorem; D005075:Biological Evolution; D007887:Fabaceae / Q000235:genetics*; D006801:Humans; D009656:North America; D058974:Phylogeography; D018609:Tibet