Coniferous forests are under severe threat of the rapid anthropogenic climate warming.Abies(firs),the fourth-largest conifer genus,is a keystone component of the boreal and temperate dark-coniferous forests and harbor...Coniferous forests are under severe threat of the rapid anthropogenic climate warming.Abies(firs),the fourth-largest conifer genus,is a keystone component of the boreal and temperate dark-coniferous forests and harbors a remarkably large number of relict taxa.However,the uncertainty of the phylogenetic and biogeographic history of Abies significantly impedes our prediction of future dynamics and efficient conservation of firs.In this study,using 1,533 nuclear genes generated from transcriptome sequencing and a complete sampling of all widely recognized species,we have successfully reconstructed a robust phylogeny of global firs,in which four clades are strongly supported and all intersectional relationships are resolved,although phylogenetic discordance caused mainly by incomplete lineage sorting and hybridization was detected.Molecular dating and ancestral area reconstruction suggest a Northern Hemisphere high-latitude origin of Abies during the Late Cretaceous,but all extant firs diversified during the Miocene to the Pleistocene,and multiple continental and intercontinental dispersals took place in response to the late Neogene climate cooling and orogenic movements.Notably,four critically endangered firs endemic to subtropical mountains of China,including A.beshanzuensis,A.ziyuanensis,A.fanjingshanensis and A.yuanbaoshanensis from east to west,have different origins and evolutionary histories.Moreover,three hotspots of species richness,including western North America,central Japan,and the Hengduan Mountains,were identified in Abies.Elevation and precipitation,particularly precipitation of the coldest quarter,are the most significant environmental factors driving the global distribution pattern of fir species diversity.Some morphological traits are evolutionarily constrained,and those linked to elevational variation(e.g.,purple cone)and cold resistance(e.g.,pubescent branch and resinous bud)may have contributed to the diversification of global firs.Our study sheds new light on the spatiotemporal evolution of global firs,which will be of great help to forest management and species conservation in a warming world.展开更多
Dear Editor,Gymnosperms,the sister group to angiosperms,comprise 13 families,86 genera,and approximately 1,000 species(Wang and Ran,2014).Despite their low species diversity,gymnosperms are found on all continents exc...Dear Editor,Gymnosperms,the sister group to angiosperms,comprise 13 families,86 genera,and approximately 1,000 species(Wang and Ran,2014).Despite their low species diversity,gymnosperms are found on all continents except Antarctica and occupy over 43% of the world's forests(Ma et al.,2023).Especially China,a global hotspot for gymnosperm diversity,hosts around 200 species encompassing all major lineages,making it the most diverse country for gymnosperms.展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(CAS)(grant nos.XDA23080000)the National Key Research and Development Program of China(grant number 2017YFA0605100)the Strategic Priority Research Program of CAS(grant no.XDB31010000).
文摘Coniferous forests are under severe threat of the rapid anthropogenic climate warming.Abies(firs),the fourth-largest conifer genus,is a keystone component of the boreal and temperate dark-coniferous forests and harbors a remarkably large number of relict taxa.However,the uncertainty of the phylogenetic and biogeographic history of Abies significantly impedes our prediction of future dynamics and efficient conservation of firs.In this study,using 1,533 nuclear genes generated from transcriptome sequencing and a complete sampling of all widely recognized species,we have successfully reconstructed a robust phylogeny of global firs,in which four clades are strongly supported and all intersectional relationships are resolved,although phylogenetic discordance caused mainly by incomplete lineage sorting and hybridization was detected.Molecular dating and ancestral area reconstruction suggest a Northern Hemisphere high-latitude origin of Abies during the Late Cretaceous,but all extant firs diversified during the Miocene to the Pleistocene,and multiple continental and intercontinental dispersals took place in response to the late Neogene climate cooling and orogenic movements.Notably,four critically endangered firs endemic to subtropical mountains of China,including A.beshanzuensis,A.ziyuanensis,A.fanjingshanensis and A.yuanbaoshanensis from east to west,have different origins and evolutionary histories.Moreover,three hotspots of species richness,including western North America,central Japan,and the Hengduan Mountains,were identified in Abies.Elevation and precipitation,particularly precipitation of the coldest quarter,are the most significant environmental factors driving the global distribution pattern of fir species diversity.Some morphological traits are evolutionarily constrained,and those linked to elevational variation(e.g.,purple cone)and cold resistance(e.g.,pubescent branch and resinous bud)may have contributed to the diversification of global firs.Our study sheds new light on the spatiotemporal evolution of global firs,which will be of great help to forest management and species conservation in a warming world.
基金supported by the Strategic Priority Research Program,Chinese Academy of Sciences(XDA23080000)the National Natural Science Foundation of China(31770238)+1 种基金Key Research Program of Frontier Sciences,Chinese Academy of Sciences(QYZDJ-SSW-SMC027)the K.W.Wong Education Foundation(GJTD-2020-05)。
文摘Dear Editor,Gymnosperms,the sister group to angiosperms,comprise 13 families,86 genera,and approximately 1,000 species(Wang and Ran,2014).Despite their low species diversity,gymnosperms are found on all continents except Antarctica and occupy over 43% of the world's forests(Ma et al.,2023).Especially China,a global hotspot for gymnosperm diversity,hosts around 200 species encompassing all major lineages,making it the most diverse country for gymnosperms.
