A Review of Current Theories and Methods in Cladistics and a Cladistic Study of Twelve Lindera Species in Eastern China

Cladistics has become a widely used method for phylogenetic reconstruction．Because of rapid improvement Of cladistic theories and methodologies,and application of new data,especially,molecular data,it is becoming realistic to reconstruct phylogenies of organisms,and to establish natural classifications based on these phylogenies．This paper reviews some current cladistic theories and methods in a practical way,such as choosing characters,defining character states,polarizing characters,analyzing data matrices, calculating consensus cladograms,choosing among multiple equally most parsimonious cladograms,estimating reliability of cladograms,and applying cladograms to classification, character evolution,and biogeography． Based on 36 morphological characters．a parsimony analysis of 12 species representing six sections in subgenus Lindera and an outgroup species from subgenus lteodaphne of the genus Lindera(Lauraceae)was conducted．The results suggest a close relationship between section Lindera and section Sphaerocarpae,which is different from the previous phylogenetic hypothesis within the genus．In the strict consensus cladogram,two species,L．megaphylla and L.chienii,from section Cupuliformes are in the most primitive and the most advanced clades respectively,indicating that the section is polyphyletic．The cladogram also suggests that section Lindera be a polyphyletic group．     

中国紫金牛属的分支分类学研究

基于60个形态学性状,对中国广义报春花科（Primulaceae s.l.）紫金牛属（Ardisia）90个分类群的系统发育关系运用分支分析方法进行了分析。采用最简约性分析得到了100个同等简约树。50%多数规则一致树的分支结构与以前建立的紫金牛亚属划分系统基本一致。外类群酸藤子属、铁仔属、密花树属聚在分支树的最基部,紫金牛属为一单系类群。形态分支树的一致性指数和保持性指数和各分支内部支持率均较低,只在种与变种或亚种之间获得较高的支持率。高木亚属、腋序亚属、短序亚属、顶序亚属处于分支树较为基部的位置,推测这四个亚属的类群在紫金牛属中较为原始;圆齿亚属和锯齿亚属共同组成一大支,二者亲缘关系紧密,推测这两个亚属为该属中最为进化的类群。结合形态学对属内系统发育关系进行了讨论和推测了一些性状的演化趋势,以期为分类修订提供依据。     

Cladistics and Biogeography of Artemisia sect. Viscidipubes and sect. Albiraotea (Compositae)

Twenty-six species and eight varieties of Sect．Viscidipubes & Sect．Albibractea are endemic to Asia．Most species of Sect．Viscidipubes are distributed from low to high altitudes and cold areas in the Hengduan-Himalayan Mountains,with only a few species extending to E or S Asia．Sect．Albibractea is distributed mainly in the subtropics and tropics,lower altitudes and moist areas in S & SE Asia,with a few species extending to the Qinling range of China．Both sections are more advanced than the other sections．They were studied by cladistic analysis and outgroup comparison．Data matrix of 55 characters from stems,leaves,inflorescences,female flowers,bisexual flowers,achenes,pollen grains and chemical constitution was employed in separate and combined studies．Eighteen most parsimonious cladograms were generated with 358 steps,consistency index of 0．72 and retention index of 0．87． 1．Within Artemisia,Sect．Viscidipubes and Sect．Albibractea are sister groups to all the other groups． 2．We support the idea to separate Sect．Viscidipubes (incl．Ser．Viscidipubes,Ser．Erlangshanenses and Ser. Pleiocephalea) and Sect．Albibractea (incl．Ser．Albibractea,Ser．Flaccidae and Ser. Anomalae)．The authors suggest that Ser．Anomalae include A．deversa and Ser．Erlangshanenses include A．zayuensis and A．yadongensis as well as Ser．Viscidipubes include A．gyitangensis and A．boreali-siamensis．As the result of the cladistic analysis,the authors tend to propose a new series, Ser．Tanguticae,incl．A．tangutica in the section． 3．We consider that SW China,especially W Sichuan,is the speciation center and the tration of the present distribution center．4．A．boreali-siamensis,only in N Thailand,is not related to the widely distributed species in Ser．Pleiocephalae,such as A．atrovirens,A．chingii and A．myriantha,but rather closely related to species,such as A．vexans,A．occidentali-sichuanensis,which are endemic to W.Sichuan and E．Xizang．     

木兰藤科系统位置评述

木兰藤科(Austrobaileyaceae)含1属2种,是系统学上最孤立的科之一。其花粉类似于最古老的被子植物化石之一:晚白垩世的棒纹粉。最新的分子系统发育研究结果表明,木兰藤科是现存被子植物的基部类群之一,其对于被子植物的起源与早期进化的研究具有重要价值。被子植物(有花植物)的起源和辐射一直是植物学家关注的热点。有关木兰藤科的系统位置一直存在争议。本文对该科系统位置的研究历史与现状进行评述。     

土壤酶学的研究进展

土壤酶在生态系统中是否作为一个组成成分,经典生态学没有明确的表述,但土壤酶在生态系统中具有重要的地位,它参与了包括土壤生物化学过程在内的自然界物质循环。介绍土壤酶的研究历史,土壤酶的检测技术、土壤酶的来源、土壤状况与土壤酶活性的关系、管理措施对土壤酶的影响等方面的研究进展,旨在推动土壤酶学的研究和利用。     

睡莲科系统位置评述

形态学研究显示睡莲科Nymphaeaceae具有许多原始性状。睡莲科又被称为“古草本”。最新的分子系统发育研究显示,睡莲科是现存被子植物系统树根部附近最早分异谱系的演化支之一,对研究被子植物(有花植物)的起源与早期进化具有重要价值,但有关睡莲科的范围和系统位置存在争议。被子植物的起源与辐射一直是植物学家关注的热点。本文对该科系统位置的研究历史与现状进行了评述。     

A classification of the genus Nothofagus (Fagaceae)

PHILIPSON, W. R. & PHILIPSON, M. N., 1988. A classification of the genus Nothofagus (Fagaceae). The genus Nothofagus is subdivided into two subgenera, two sections and three subsections, employing characters of the pollen, cupule and vernation, together with the incidence of leaf-fall. The subdivision into subgenera also agrees with present geographical distribution and with characters of the secondary xylem. One subgeneric and one subsectional name are new. Reasons are given for departures from previous classifications.     

富硒虫草的研究进展

虫草是传统名贵中药,具有抗癌、抗菌、调节免疫、降血脂、降血糖等广泛的药理作用;硒是人体必需的微量元素,具有抗癌、抗氧化、抗衰老等多种生理功能,与许多种疾病密切相关。利用虫草菌将无机硒转化为有机硒,实现虫草与硒的有机结合,研究功能更好的富硒虫草,无论作为药用、保健品还是补硒食品都具有很重要的现实意义。本文综述二十余年来富硒虫草的研究状况。     

遗鸥研究概述

叙述自遗鸥（Larus relictus)被确认为有效物种以来30余年中世界范围内对遗鸥的主要研究结果与对遗鸥认知发展的概况,总的来讲,遗鸥作为环蒙古高原的繁殖分布,为荒漠-半荒漠生态条件下的典型鸟种,具4个相对独立的繁殖种群,取湖心岛为繁殖生境,遗鸥当年幼鸟呈辐射方式作最初扩散。而其主要越冬地和越冬种群至今尚不明了,由于气候变化造成繁殖生境的不稳定,应是导致遗鸥繁殖群呈较强动态变化的重要原因。     

A Report on "One Day Symposium on Numerical Cladistics"

A recent symposium on numerical cladistics held at the American Museum of Natural History in New York City, addressed novel methods for searching tree space, applications of randomizations in cladistic analysis, and data management. One of the major concerns in systematics is that of finding the global optimum in tree length. The space to search is complex because it includes many local optima. It is a difficult task to escape local optima without a great loss in efficiency. The ideal is to search among suboptimal topologies and still obtain an answer in a reasonable amount of time. Nixon presented a new family of methods called "parsimony ratchet," which are successful at escaping local optima. Moilanen presented a new program which may have similar advantages. Two presentations, one by Goloboff and Farris and another by Farris, Goloboff, Källersjö, and Oxelman, introduced modifications to parsimony jackknifing that improved its accuracy when compared to normal heuristic searches. Wheeler discussed the advantages of new methods of analyzing DNA and protein sequence data, which eliminate multiple alignment; the most recent one packs nucleotides into strings which constitute the new characters. Siddall discussed different applications of randomization in cladistics and their logical consistency, finding some more acceptable than others. Nixon and Carpenter presented a new program for managing data. This symposium will probably be a landmark judging from the originality and practicality of the points presented.     

生态系统模拟模型的研究进展

从四个方面概述了生态系统模拟模型的发展现状：1)个体及种群,种群动态模型主要模拟在一个生境中单个种的动、植物个体出生或发芽、成长及其死亡过程,还有种内竞争和种间相互作用,主要分析生境中生物之间的相互作用。主要概述了林窗模型和土壤一植物一大气系统模型。2)群落与生态系统,概述了生态系统生产力模型、生物地球化学循环模型及演替模型。主要模拟植物种类在整个生态系统发展过程中的变化,以及植被类型的转变和相关的生物地球化学循环过程的改变,从而反映生物群落对气候变化的响应。3)景观生态系统,景观动态研究包含了时空两个方面的动态变化,一般可分为随机景观模型和基于过程的景观模型。随机模型用于模拟群落格局在演替过程中的动态变化等,基于过程的景观模型深入研究组成景观的各生态系统的空间结构。4)生物圈与地球生态系统,基于过程的陆地生物地球化学模式被用来研究自然生态系统中碳和其它矿物营养物质的潜在通量和蓄积量,较为流行的模式有陆地生态系统模式TEM、CENTURY、法兰克福生物圈模式FBM、Biome-BGC、卡内基-埃姆斯-斯坦福方法CASA等。这些模式己被用于估算自然生态系统对大气CO2加倍及相关气候变化在区域和全球尺度的平衡响应。最后,结合实际工作展望了生态系统模拟模型在各方面的发展方向。     

分支系统学简介

分支系统学是本世纪70年代以来发展起来的一个新的系统学派。本文扼要地介绍了分支系统学的创立、历史和发展,分支系统学的基本概念、特征分析法以及分支系统学的广泛应用给现代生物系统学所带来广泛影响和冲击。     

齿蟾属的系统学研究进展

齿蟾属(Oreolalax)为中国特有属,主要分布在我国西南地区。本文对该属的系统学研究进行了综述,包括属的建立与物种组成、地理分布特征、细胞分类学、系统发育研究历史,以及尚需研究或进一步研究的问题。     

分支系统学当前的理论和方法概述及华东地区山胡椒属十二个种的分支系统学研究

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。     

单子叶植物科级分类阶元形态性状分支分析

基于93个形态形状,采用13个被子植物基部类群做为外类群,对49个单子叶植物科级分类阶元进行了分支系统学分析。经过简约性分析,得到了1684棵同等最大简约分支树。严格一致树的分支结构图表明：1）古草本类植物和单子叶植物是姐妹群关系;2）具有网状脉的类群,薯蓣科,菝葜科,百部科是单子叶植物的最基部类群。由于性状状态间存在着较多的平行和逆转进化,这在一定程度上影响了系统发育重建的准确性;所选择的性状状态之间的演化很可能是平行的、多次的或者是特化的状态,因此这样复杂的演化关系的探索关键在于找到一些能确切反映其系统演化关系的形态性状。目前很难通过简约化的形态分支分析来解开整个单子叶植物的起源和演化之谜。为了避开对系统学分析造成干扰的误导性状,形态数据结合DNA序列分析很可能是必需的。     

姬缘蝽科系统发育初探：（异翅亚目：缘蝽总科）

本文通过对姬缘蝽科１４属的比较形态学研究,以支序分析方法探讨了各类间的系统发育关系,３其结果证明姬缘蝽科为一明显单系群,并支持Ｃｈｏｐｒａ（１９６７）系统中大部分族的划分意见,但因支序图中玛缘蝽族和姬缘蝽亚科为并系群,从而对Ｃｈｏｐｒａ系统中亚科的划分及玛缘蝽族是否成立提出疑问,并认为已有系统中的“红缘蝽亚科”应降为族级。文中还将支序分析结果与经前作者的系统发育意见相比较,认为本文所提出的关于该科     

异型雄蕊的研究进展

就异型雄蕊的概念、在被子植物中的分布、在传粉过程中的作用及其发育进行了概述,并对未来的研究方向作一展望.异型雄蕊指一朵花内的雄蕊在形态、大小、颜色等方面有显著的区别,并存在不同程度分工的现象.异型雄蕊在野牡丹科、茄科、干屈菜科、豆科、雨久花科等多个科中都有分布,但其分化与程度常随类群而异.虽然人们对于这一现象的认识由来已久,但研究尚不深入.对于异型雄蕊的研究可以加深人们对植物与其传粉者之间关系的理解,并为传粉生物学与植物繁育系统研究提供新的视角和启示.     

Congruence between phylogenetic and stratigraphic data on the history of life

The quality of the fossil record and the accuracy of reconstructed phylogenies have been debated recently, and doubt has been cast on how far current knowledge actually reflects what happened in the past. A survey of 384 published cladograms of a variety of animals (echinoderms, fishes, tetrapods) shows that there is good agreement between phylogenetic (character) data and stratigraphic (age) data, based on a variety of comparative metrics. This congruence of conclusions from two essentially independent sources of data confirms that the majority of cladograms are broadly accurate and that the fossil record, incomplete as it is, gives a reasonably faithful documentation of the sequence of occurrence of organisms through time.