Phylogenomics,biogeography,and evolution of the blue-or white-fruited dogwoods(Cornus)-Insights into morphological and ecological niche divergence following intercontinental geographic isolation  

作　　者：Kira Lindelof Julieta ALindo Wenbin Zhou Xiang Ji Qiu-Yun(Jenny)Xiang 

机构地区：[1]Department of Plant and Microbial Biology,North Carolina State University,Raleigh,NC 27695-7612,USA [2]Department of Biomathematics,David Geffen School of Medicine,University of California,Los Angeles,CA 90095-1766,USA

出　　处：《Journal of Systematics and Evolution》2020年第5期604-645,共42页植物分类学报（英文版）

摘　　要：The eastern Asian(EA)-eastem North American(ENA)floristic disjunction represents a major pattern of phytogeography of the Northern Hemisphere.Despite 20 years of studies dedicated to identification of taxa that display this disjunct pattern,its origin and evolution remain an open question,especially regarding postisolation evolution.The blue-or white-fruited dogwoods(BW)are the most species-rich among the four major clades of Cornus L.,consisting of-35 species divided into three subgenera(subg.Yinquania,subg.Mesomora,and subg.Kraniopsis).The BW group provides an excellent example of the EA-ENA floristic disjunction for biogeographic study due to its diversity distribution centered in eastern Asia and eastern North America,yet its species relationships and delineation have remained poorly understood.In this study,we combined genome-wide markers from RAD-seq,morphology,fossils,and climate data to understand species relationships,biogeographic history,and ecological niche and morphological evolution.Our phylogenomic analyses with RAxML and MrBayes recovered a strongly supported and well-resolved phylogeny of the BW group with three intercontinental disjunct clades in EA and ENA or Eurasia and North America,of which two are newly identified within subg.Kraniopsis.These analyses also recovered a potential new species but failed to resolve relationships within the C.hemsleyi-C.schindleri complex.In an effort to develop an approach to reduce computation time,analysis of different nodal age settings in treePL suggests setting a node's minimum age constraint to the lower bound of a fossil's age range to obtain similar ages to that of BEAST.Divergence time analyses with BEAST and treePL dated the BW stem back to the very Late Cretaceous and the divergence of the three subgenera in the Paleogene.By integrating fossil ages and morphology,a total evidence-based dating approach was used in conjunction with time-slice probabilities of dispersal under a DEC model to resolve ancestral ranges of each disjunct in the Miocene:Eurasi

关 键 词：BIOGEOGRAPHY CORNUS eastern Asian-eastern North American disjunction ecological niche and morphospace PHYLOGENOMICS RAD-seq 

分 类 号：Q94[生物学—植物学]