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1.
本概述了当前分支系统学研究中涉及的主要理论和方法,包括性状的选取、性状状态和极性的确定、数据矩阵的分析计算、结果分支图的处理、分支图可靠性的评价及分支图的应用。本同时以华东地区樟科山胡椒属Lindera12个种的分支系统学研究为例,讨论了用形态性状进行分支系统学研究中可能遇到的问题,也揭示了一些分支系统学与传统的系统学在应用性状推导进化关系上的不同点。对这12个种的分支系统学研究得出了一些不同  相似文献   

2.
以礼草属系统发育的分析   总被引:7,自引:2,他引:5  
基于分支系统学的原理和方法。对禾本科以礼草属进行了系统发育分析,以礼草属是个单系在群,它的32个外部性状选作极性分析。鹅观草属中的肃草作为外类群,采用PAUP程序对矩阵进行运算,获得了1个最简约的谱系分支图。在分支图上,以民礼草属26个种可以归为3个组,但不适合于划分系,3个组中各组包含的种数分别与传统分类的3个组基本吻合,从而支持了传统分类的结果。同时,分支图还展示了各个类群间的亲缘演化关系,其  相似文献   

3.
本文概述了当前分支系统学研究中涉及的主要理论和方法,包括性状的选取、性状状态和极性的确定、数据矩阵的分析计算、结果分支图的处理、分支图可靠性的评价及分支图的应用。本文同时以华东地区樟科山胡椒属Linderal2个种的分支系统学研究为例,讨论了用形态性状进行分支系统学研究中可能遇到的问题,也揭示了一些分支系统学与传统的系统学在应用性状推导进化关系上的不同点。对这12个种的分支系统学研究得出了一些不同于传统系统学方法所推测的山胡椒属内的系统发育关系,如分支系统学研究显示山胡椒组和球果组很近缘。在严格一致性分支图上,杯托组的黑壳楠和江浙山胡椒分别位于最原始和最进化的分支,表明这个组是复系类群。分支图也显示山胡椒组可能是复系类群。  相似文献   

4.
文章简明介绍了现代分支系统学的分支格局原理和组份分析方法,并应用于李朝銮(1990,表2)的中国白粉藤属14种植物数据的分支分析。得出13个可能的最简约的二歧分支图,图长41步。这些分支图与李(1990)图2:13的比较表明,中值淘汰法不如组份分析方法有效,而且中值淘汰法有表相学和(或)进化系统学的疑问。  相似文献   

5.
子树分析和TASS程序及其在锦鸡儿属植物中的应用   总被引:5,自引:0,他引:5  
子树分析和三分法 (TASS)程序是历史生物地理学中分布区关系的一种分析途径。它以分类群分支图为基础 ,以剔除其中分布区关系相悖理的结点并确定具信息的子树为目标 ,以便更有效地利用分布区信息。对分布区关系可以用若干子树和一个分布区分支图来表示。对锦鸡儿属 (Caragana)植物 72种和 13个分布区的子树分析和TASS程序运算后 ,得到 7个具信息的子树 ,它们分别表达了锦鸡儿属属内组、系所具有的分布区关系。属的分布区分支图也表达了 13个分布区的关系。与以前我们对本属成分分析的结果相吻合。  相似文献   

6.
子树分析和三分法(TASS)程序是历史生物地理学中分布区关系的一种分析途径.它以分类群分支图为基础,以剔除其中分布区关系相悖理的结点并确定具信息的子树为目标,以便更有效地利用分布区信息.对分布区关系可以用若干子树和一个分布区分支图来表示.对锦鸡儿属(Caragana)植物72种和13个分布区的子树分析和TASS程序运算后,得到7个具信息的子树,它们分别表达了锦鸡儿属属内组、系所具有的分布区关系.属的分布区分支图也表达了13个分布区的关系.与以前我们对本属成分分析的结果相吻合.  相似文献   

7.
鹅观草属的系统发育分析   总被引:2,自引:0,他引:2  
蔡联炳  王玉金 《植物研究》2001,21(4):554-560
根据分支系统学的原理和方法, 对禾本科鹅观草属进行了系统发育分析。鹅观草属传统分类上的18 个系被确定为终端类群, 来自形态学、解剖学、细胞学和孢粉学的23 个性状被选作建立矩阵的依据;雀麦族中的短柄草属作为外类群被用于外部性状的极性识别, 过去分析过的性状资料被用于微观特征的极性判断;采用PAUP 程序对矩阵进行运算, 共获得6 个同等简约的谱系分支图, 其中具最低f-比值的图被选作分支分析的基础。结果表明, 分支图上显示的组、系划分与传统分类的基本一致, 各类群间的演化关系与过去凭借单一证据所作的零散推断也基本吻合。所不同的是半颖组各支类群不是共祖起源, 可能具有复杂的内部组成;在个别系间, 分支图展现的类群位置与宏观分析的存在差异。  相似文献   

8.
中国葛属(Pueraria DC.)的研究   总被引:21,自引:1,他引:21  
本文对国产葛属植物9种2变种进行了全面整理.对其中的主要类群进行了深入的研究.通过野外考察,腊叶标本的研究和细胞染色体的计数.使对中国葛属植物有一个较为全面的了解。  相似文献   

9.
葛根的研究与开发现状   总被引:23,自引:0,他引:23  
阐述了葛属植物的种类和分布,对于葛根的营养保健作用、药理作用及机理,对国内外葛根保健食品的研究开发现状进行了分析。  相似文献   

10.
裸藻类植物的分支系统学研究   总被引:1,自引:0,他引:1  
本文选取了裸藻类的33个属级分类单位,以及它们的35个性状,利用分支系统学的原理和方法,对性状的演化极性进行了分析,同时对性状间的极性关系进行了和谐性分析,使性状间极性关系处在较为合理的状态,然后建立了分支分析的数据矩阵。应用徐克学建立的“演化极端结合法”进行微机运算.得简约系数远小于1(o.2159)的分支谱系图。根据分支诺系图对裸藻类的系统发育关系进行了探讨,井与已有的关于裸藻类分类系统和演化假设进行了比较。在此基础上按照裸藻类的亲缘关系及单系原则,对裸藻类的分类等级进行了划分,初步提出了建立1门1纲5目的分类系统。按照在分支谱系中的演化地位,认为裸藻属的5个亚属,明显地都应是独立的属。同时对裸藻类的共生起源与演化的关系也进行了讨论。  相似文献   

11.
The sturgeon subfamily Scaphirhynchinae contains two genera of obligate freshwater sturgeon: Scaphirhynchus and Pseudoscaphirhynchus, from North America and Central Asia, respectively. Both genera contain morphologically variable species. A novel data set containing multiple individuals representing four diagnosable morphological variants for two species of Pseudoscaphirhynchus, P. hermanni and P. kaufmanni, was generated. These data were used to test taxonomic hypotheses of monophyly for the subfamily Scaphirhynchinae, monophyly of both Scaphirhynchus and Pseudoscaphirhynchus, monophyly of P. hermanni and P. kaufmanni, and monophyly of the recognized morphological variants. Monophyly of the subfamily Scaphirhynchinae is consistently rejected by all phylogenetic reconstruction methodologies with the molecular character set while monophyly of both river sturgeon genera is robustly supported. The molecular data set also rejects hypotheses of monophyly for sampled species of Pseudoscaphirhynchus as well as monophyly for the recognized intraspecific morphological variants. Interestingly both Scaphirhynchus and Pseudoscaphirhynchus demonstrate the same general pattern in reconstructed topologies; a lack of phylogenetic structure in the clade with respect to recognized diversity. Despite rejection of monophyly for the subfamily Scaphirhynchinae with molecular data, reconstructed hypotheses from morphological character sets consistently support monophyly for this subfamily. Disparities among the data sets, as well as reasons for rejection of monophyly for Scaphirhynchinae and species of Scaphirhynchus and Pseudoscaphirhynchus with molecular characters are examined and a decreased rate of molecular evolution is found to be most consistent with the data.  相似文献   

12.
The African wattle-eyes (genera Platysteira and Dyaphorophyia) comprise 10 species endemic to Africa. We analyzed both mitochondrial and nuclear DNA sequence data to test the monophyly of this group and its two genera, provide a preliminary assessment of species limits, and gain insight into the phylogeographic history of the wattle-eye radiation. Analyses based on mitochondrial ND2 sequences failed to recover wattle-eye monophyly, but the alternatives were not well-supported. In contrast, analyses of two nuclear introns (myoglobin intron-2 and beta-fibrinogen intron-5) recovered wattle-eye monophyly, as did combined analyses of mitochondrial and nuclear data. These analyses, however, did not support reciprocal monophyly of the two wattle-eye genera typically recognized, suggesting instead that Platysteira is nested within a paraphyletic Dyaphorophyia. The diversification of most wattle-eye species and many subspecies occurred through the divergence of allopatric populations well before the Pleistocene. Species and subspecies with disjunct distributions are typically characterized by deep genetic divergences, suggesting that many of these populations are evolutionary independent and could be recognized as additional phylogenetic species. In D. castanea and D. chalybea, for example, divergent haplotypes from geographically disjunct populations were paraphyletic with respect to those of D. tonsa and D. jamesoni, respectively. Similarly, Platysteira laticincta is highly divergent from its sister taxon P. peltata ( approximately 9.5% ND2 sequence divergence), consistent with species level recognition of this endangered species. In contrast, more broadly distributed taxa inhabiting a greater diversity of habitats (e.g., P. peltata and P. cyannea) show evidence of gene flow and connectivity among regions, suggesting that previously isolated populations expanded and fused into one another. Our study provides a framework for additional analyses of intraspecific phylogeography and species limits in these colorful birds.  相似文献   

13.
? Premise of the study: Pueraria (Leguminosae, Papilionoideae) is native in East Asia, South Asia, Southeast Asia, and Oceania and is well known as a rampant invasive weed in the southeastern United States (P. montana; better known as kudzu), but relatively little is known about its early evolution and biogeographic origin. ? Methods: On the basis of comparative analyses of the fruit and leaflet architecture of closely related extant and fossil taxa, we studied the fossil history and biogeography of Pueraria. ? Key results: Fossil Pueraria is recognized on the basis of distinctive fruit and foliage from the Mio-Pliocene of middle latitudes in China, Japan, Abkhazia, and Croatia. Recognition of P. miothunbergiana from the Mio-Pliocene of China and Japan is reinforced by a trifoliolate leaf as well as isolated lateral and terminal leaflets. Pueraria shanwangensis sp. nov. represents the first recognition of fossil Pueraria fruits. This fruit species co-occurs with P. miothunbergiana in the Middle Miocene Shanwang flora and possibly represents the same population. Pueraria maxima (Unger) comb. nov., previously named as Dolichites maximus or Desmodium maximum, is recognized on the basis of leaflets from the Miocene of Croatia and Abkhazia. Other prior fossil reports of Pueraria and Dolichites are reevaluated. ? Conclusions: Pueraria had begun to diversify by at least the Middle Miocene and had spread into the Mio-Pliocene subtropical and temperate floras of the Balkan Peninsula, the Caucasus, and eastern Asia, which suggests the present diversity of this genus in tropical Asia and Oceania might have originated from the mid-latitudes of Eurasia.  相似文献   

14.
Ariid monophyly and intrafamilial relationships are investigated based on cladistic analysis of 230 morphological characters. Terminal taxa examined include whenever possible type‐species, or the most morphologically similar species to the type‐species of the nominal genera, and the largest possible number of species, including cleared and stained specimens, available in zoological collections. Previous hypotheses about monophyly of the Ariidae are strongly corroborated by new synapomorphies discovered in the present study. The subfamily Galeichthyinae and the remaining ariids are strongly supported by new morphological characters. The monotypic subfamily Bagreinae is recognized as the sister group to all nongaleichthyin ariids, supported by a large series of exclusive synapomorphies. A new concept of Ariinae is presented: the subfamily is found to be unequivocally monophyletic and includes all ariid genera, except Galeichthys and Bagre. New data supporting the monophyly of the genera included in the Ariinae are introduced and previous hypotheses of monophyly, species composition, morphological definition, and relationships are reviewed and discussed.  相似文献   

15.
鄂西产三种野生葛总黄酮含量的紫外分光光度法测定   总被引:6,自引:0,他引:6  
鄂西产三种野生葛总黄酮含量的紫外分光光度法测定李石生刘欣邓京振赵守训(中国药科大学天然药物化学教研室,南京210038)Determinationoftotalflavonoidin3wildspeciesofPuerariafromWestHub...  相似文献   

16.
Pueraria radix (the dried root of Pueraria plant) is known as a traditional Chinese drug. Hairy roots of Pueraria lobata (Willd.) Ohwi, P.lobata var. montana and P. phaseoloides (Roxb.) Benth. transformed by Agrobacterium rhizogenes (Riker et al .) Conn R1601 were developed directly from the surface of sterile leaves in vitro . The transformation frequency was 16.6%, 16.2% and 26.6%, respectively. All hairy roots in the three species displayed the typical phenotypes of rapid growth, highly branched and plagiotropism, and also exhibited hormone autotrophy and resistance to kanamycin.The genetic transformations were confirmed by opine paper electrophoretic analysis, rol gene PCR amplification and molecular hybridization.  相似文献   

17.
Abstract.— The genealogies of samples of orthologous regions from multiple species can be classified by their shapes. Using a neutral coalescent model of two species, I give exact probabilities of each of four possible genealogical shapes: reciprocal monophyly, two types of paraphyly, and polyphyly. After the divergence that forms two species, each of which has population size N , polyphyly is the most likely genealogical shape for the lineages of the two species. At ∼ 1.300 N generations after divergence, paraphyly becomes most likely, and reciprocal monophyly becomes most likely at ∼1.665 N generations. For a given species, the time at which 99% of its loci acquire monophyletic genealogies is ∼5.298 N generations, assuming all loci in its sister species are monophyletic. The probability that all lineages of two species are reciprocally monophyletic given that a sample from the two species has a reciprocally monophyletic genealogy increases rapidly with sample size, as does the probability that the most recent common ancestor (MRCA) for a sample is also the MRCA for all lineages from the two species. The results have potential applications for the testing of evolutionary hypotheses.  相似文献   

18.
The phylogenetic relationships of Prionospio Malnigren, 1867 are estimated in two parsimony analyses. The first analysis includes type and other species of Prionospio (Prionospio) Malmgren. 1867. P. (Mitiuspio) Foster, 1971, P. (Aqiriluspio) Foster, 1971, Apopriotiospio Foster, 1969, Aitrospio Maciolek. 1981, Paraprionospio Caullery, 19 14. Streblospio Webster, 1897, Laubieriellus Maciolek, 1981, and Orthoprionospio Blake & Kudenov, 1978; all members of a group of closely related taxa. Prionospio banyulensis Laubier, 1966 is included as a separate taxon since its relationship to Priotiospio has been questioned. The single most parsimonious tree supports monophyly of a group containing P. (Prionospio), P. (Minuspio), P. (Aqirilaspio) , and Apopriotiospio.
Based on the tree topology from the first analysis, 14 species belonging to different subgenera of Priotiospio and Apopriotiospio are included in a more restricted analysis, with Orthoprionospio cirrformia Blake & Kudenov, 1978 as outgroup. Three equally parsimonious trees were obtained, differing only in the positions of Prionospio ehlersi Fauvel, 1928, Prionospio henriki Hylleberg & Nateewathana, 1990, and Prionospio rugosa Sigvaldadóttir, 1997.
The results of the two analyses are compared to earlier classifications. As support is lacking for monophyly of both subgenera P. (Minuspio) and P. (Aquilaspio) , they are synonymized with P. (Prionospio). Apoprionospio cannot be justified as a separate genus without making Priotiospio paraphyletic, and is synonymized with Prionospio. Two species, P. banyulensis and P. pilkena Wilson, 1990, are transferred to Aurospio. A checklist of species belonging to Prionospio sesu lato , together with information on type locality and location of type specimens, is included.  相似文献   

19.
基于78种直翅目昆虫的18S rRNA基因全序列构建了直翅目各主要类群间的系统发育关系。本研究的结果支持直翅目的单系性,但不支持蝗亚目和螽亚目各自的单系性;直翅目下除蜢总科和蝗总科外各总科的划分多数与Otte系统相一致;蜢总科的单系性得不到支持;蝗总科的剑角蝗科、斑腿蝗科、斑翅蝗科、网翅蝗科和槌角蝗科5科均不是单系群,各物种间的遗传距离差异不大,应合并为一科,即蝗科;本研究支持将Otte系统中蚱总科和螽蟖总科下各亚科级阶元提升为科级阶元;18S rRNA基因全序列可以作为划分科级阶元的工具,当位于同一分支上互成姐妹群的类群间的遗传距离超过1%时,这几个类群属于不同的科;但由于其在进化上的保守性,18S rRNA基因只能用于纲目等高级阶元间关系的研究,而由其获得的总科以下阶元间的关系并不可靠。  相似文献   

20.
A Preliminary Approach to the Phylogeny of the Genus Paspalum (Poaceae)   总被引:1,自引:0,他引:1  
Souza-Chies TT  Essi L  Rua GH  Valls JF  Miz RB 《Genetica》2006,126(1-2):15-32
  相似文献   

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