|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Molecular phylogenetic analysis of Leibnitzia Cass.(Asteraceae:Mutisieae:Gerbera-complex),an Asian-North American disjunct genus显示文摘Leibnitzia comprises six species of perennial herbs that are adapted to high elevation conditions and is one of only two Asteraceae genera known to have an exclusively disjunct distribution spanning central to eastern Asia and North America.Molecular phylogenetic analysis of Leibnitzia and other Gerbera-complex members indicates that Leibnitzia is monophyletic,which is in contrast with our expectation that the American Leibnitzia species L. lyrata and L.occimadrensis would be more closely related to another American member of the Gerbera-complex,namely Chaptalia.Ancestral area reconstructions show that the historical biogeography of the Gerbera-complex mirrors that of the entire Asteraceae,with early diverging lineages located in South America that were followed by transfers to Africa and Eurasia and,most recently,to North America.Intercontinental transfer of Leibnitzia appears to have been directed from Asia to North America.Independent calibrations of nuclear(ribosomal DNA internal transcribed spacer region)and chloroplast(trnL-rpl32 intron)DNA sequence data using relaxed clock methods and either mean rate or fossil-based priors unanimously support Miocene and younger divergence times for Gerbera-complex taxa.The ages are not consistent with most Gondwanan vicariance episodes and,thus,the global distribution of Gerbera-complex members must be explained in large part by long-distance dispersal.American species of Leibnitzia are estimated to have diverged from their Asian ancestor during the Quaternary(ca.2 mya)and either migrated overland to North America via Beringia and retreated southwards along high elevation corridors to their present location in southwestern North America or were dispersed long distance. | Kristen E.BAIRD Vicki A.FUNK Jun WEN Andrea WEEKS | 2010 | Journal of Systematics and Evolution2010，48，3： | 2 |
| 2 | Dispersal and adaptive radiation of Bidens(Compositae)across the remote archipelagoes of Polynesia显示文摘The genus Bidens(Compositae)comprises c.230 species distributed across five continents,with the 41 Polynesian species displaying the greatest ecomorphological variation in the group.However,the genus has had a long and complicated taxonomic history,and its phylogenetic and biogeographic history are poorly understood.To resolve the evolutionary history of the Polynesian Bidens,152 individuals representing 91 species were included in this study,including 39 of the 41 described species from Polynesia.Four chloroplast and two nuclear DNA markers were utilized to estimate phylogenetic relationships,divergence times,and biogeographic history.Bidens was found to be polyphyletic within Coreopsis,consistent with previous assessments.The Polynesian radiation was resolved as monophyletic,with the initial dispersal into the Pacific possibly from South America to either the Hawaiian or Marquesas Islands.From the Marquesas,Bidens dispersed to the Society Islands,and ultimately to the Austral Islands.The initial diversification of the crown group in the Pacific is estimated to have occurred^1.63 mya(0.74-2.72,95%HPD),making Polynesian Bidens among the youngest and most rapid plant diversification events documented in the Pacific.Our findings suggest that relatively rare long-distance dispersal and founder-event speciation,coupled with subsequent loss of dispersal potential and within-island speciation,can explain the repeated and explosive adaptive radiation of Bidens throughout the archipelagoes of Polynesia. | Matthew L.Knope Vicki A.Funk Melissa A.Johnson Warren L.Wagner Erin M.Datlof Gabriel Johnson Daniel J.Crawford JMauricio Bonifacino Clifford W.Morden David H.Lorence Kenneth R.Wood Jean-Yves Meyer Sherwin Carlquist | 2020 | Journal of Systematics and Evolution2020，58，6： | 0 |
| 3 | Thistle be a mess:Untangling the taxonomy of Cirsium(Cardueae:Compositae)in North America显示文摘Cirsium(i.e.,“thistles”)are one of the most taxonomically challenging groups of Compositae in North America.This study represents the first attempt to infer a broadly sampled phylogeny of Cirsium in North America.The two main objectives are to:(i)test whether currently hypothesized species variety complexes(C.arizonicum,C.clavatum,C.eatonii,and C.scariosum)constitute monophyletic lineages,and(ii)recircumscribe any taxa that are identified as problematic.Phylogeny reconstructions based on DNA sequence data from two nuclear ribosomal regions and four plastid markers were used to infer evolutionary lineages and test species’delimitations.Eight species varietal complexes were resolved as polyphyletic.We recircumscribed these complexes and in doing so found evidence to support the recognition of six new taxa.We hypothesize that the extensive taxonomic difficulty within Cirsium is the result of several factors:(i)previously undescribed taxa,(ii)inadequate representation of taxa from herbarium specimens,(iii)phenotypic convergence,(iv)hybridization,and(v)incipient speciation.While we can provide evidence to support the recircumscription of some taxa,others remain unresolved.Therefore,we are working on a phylogenomic study of North American Cirsium to answer remaining taxonomic questions as well as provide a robust framework for biogeographic studies. | Jennifer R.Ackerfield David J.Keil Wendy C.Hodgson Mark P.Simmons Shannon D.Fehlberg Vicki A.Funk | 2020 | Journal of Systematics and Evolution2020，58，6： | 0 |
| 4 | 添加剂对功能纤维在纺织加工过程中摩擦性能的影响显示文摘项目目的是通过向纺丝液中加入添加剂,提高功能纤维的加工性能。通过对纤维加工性能的综合分析,采取了诸多有效的方法:对前纺制备过程或保护涂层的改性,对后纺加工参数的改进,以及对其他设备参数的调整等,对实际纺织生产过程中存在的问题进行了改进。 | T.Stegmaier T.Hager A.Funk W.Wunderlich M.Dauner H.Bttcher J.Schneider J.Knopf G.T.Gresser 陈书云 | 2016 | 国际纺织导报2016，44，2： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员