禾本科植物的起源,进化及分布

禾本科植物的起源、进化及分布韩建国樊奋成李枫（中国农业大学草地研究所,北京１０００９４）ＯＲＩＧＩＮ,ＥＶＯＬＵＴＩＯＮＡＮＤＤＩＳＴＲＩＢＵＴＩＯＮＯＦＴＨＥＧＲＡＭＩＮＥＡＥＨａｎＪｉａｎ－ｇｕｏＦａｎＦｅｎ－ｃｈｅｎｇＬｉＦｅｎｇ（Ｇｒａｓｓｌ...     

禾本科植物幼苗性状的聚类分析

本文用201种禾本科植物幼苗的60个形态和解剖性状进行了聚类分析,将禾本科植物分为四个大类(一级聚合单位)—狐茅类(Festucoid)、黍类(Panicoid),竹类(Bambusoid)和画眉草类(Eragrostidoid)。这四类基本上与分类系统中的亚科相吻合,只是芦竹亚科植物的幼苗分散聚到了其它类中。推测芦竹亚科是一个比较原始的类群,狐茅亚科、黍亚科和画眉草亚科可能是在芦竹亚科的基础上进化而来的。 除个别种外,大多数同属的种在较低的聚合水平上聚在一起,超族在亚聚合单位中基本上能够反映出来。 研究证明禾本科植物的幼苗性状在禾本科植物分类中具有重要的分类学意义。     

裸子植物的幼苗类型及其进化关系

裸子植物的幼苗可分为3个类型、8个亚型。即：1．苏铁型,包括苏铁亚型、银杏亚型、南洋杉亚型;2．松型,包括杉亚型,松亚型,麻黄亚型;3．买麻膝型,包括买麻滕亚型,百岁兰亚型。类型和亚型都有特征描述,并有一个检索表。文中首先讨论了种子的起源是多元的,因而裸子植物的起源也应是多元的,是前裸子植物不同类型平行进化的结果。 又根据裸子植物幼苗类型的形态特征,提出裸子植物有4条进化路线,即：苏铁路线,银杏路线,松柏路线和买麻滕路线。还讨论幼苗类型之间的进化关系,认为除买麻滕型幼苗因其形态特殊有自己独特的发展路线外,总的趋势是由留土萌发向出土萌发发展。     

双子叶植物幼苗类型及其可能的演化关系

根据幼苗形态特征,把双子叶植物幼苗划分为18个类型9个亚型,用图解释了幼苗类型之间的进化关系。双子叶植物幼苗类型进化的主线是:暗罗型（子叶具吸收功能,留土）→紫玉盘型（子叶具吸收功能,留于种壳中,下胚轴伸长）→木兰型（子叶具吸收兼光合功能）→蜡梅型（子叶具光合功能）→樱型（子叶具光合兼贮藏功能）→樟型（子叶具贮藏功能）,其他类型或亚型则为进化的旁支或盲支。根据幼苗类型来判断,现存被子植物最古老的科应为番荔枝科。     

昆虫进化与植物的关系

<正> 地球在大约35亿年前开始出现生物。到目前,在地球上生存的生物约在200万种以上。它们都是过去绝灭种类的后代,渊源于共同的祖先,经历了从无到有、从少到多、从低级到高级的发展演变过程。不同种类之间常存在着相互适应,关联进化的现象,当今地球上最为繁盛的昆虫种群就与植物存在着互适进化的关系。     

漫谈昆虫进化与植物的关系

一、昆虫进化的历程以三叶虫为祖先的节肢动物,是自距今约六亿年的寒式纪从环节动物的祖先分化而来,这可以从解剖学和比较形态学的研究结果来证明,节肢动物的循环系统位于消化道的背面,神经系统则位于消化道的腹面,;而且,低等的节肢动物其附肢分化也不明显,极似于环节动物的疣足。现今的许多研究也表明,节肢动物至少是由类似于环节动     

国家自然科学基金委重大项目“禾本科植物的适应性辐射及其进化机制”结题综述

国家自然科学基金委重大项目"禾本科植物的适应性辐射及其进化机制"利用比较形态学、分子系统学、进化发育生物学、古生物学等多方面证据,通过多学科交叉的方法探讨了禾本科植物中出现的适应性辐射现象及其机制,在禾本科的系统发育关系以及适应性辐射的基本式样、生物和非生物环境因素在物种适应和分化以及物种快速形成中的作用、基因组大小及其结构变异以及突变、重复和调控模式变化对适应性辐射过程中关键性状(功能)的影响等方面取得了重要进展,在人才培养、国际合作和实验体系建立等方面极具特点。该项目的顺利完成为更好地阐明植物多样性形成的原因与机理奠定了良好的基础。     

植物与昆虫的协同进化

据统计地球上的植物约30万种,而以植物为食的昆虫约48万种,几乎没有一种植物能免受昆虫的危害。也许人们很容易认为,植物不能运动,对取食者毫无招架之功,只能充当随时光顾的昆虫的美餐。事实上植食性昆虫可谓冒着“杀身之祸”顶着巨大的选择压力、和植物共同经历了上亿年的发展进化才“保住”了今日的饭     

中国和邻近地区杉科特有植物的核型及其进化水平的初步研究

中国和邻近地区杉科特有植物的核型类型,柳杉属、水松属、水杉属均为“1A”,杉木属、台湾杉属分别为“1B”和“2B”,它们的进化水平似依序递增并组成A-柳杉属——水松属——台湾杉属和L-水杉属——杉木属二条演化路线。该结果得到某些形态学性状和古植物学的支持,基本上适用于整个杉科。     

大熊猫颅骨、下颌骨及牙齿特征在进化上的意义

本文对大熊猫颅骨形态及牙齿结构进行了研究,认为大熊猫与始熊猫的裔征不同于熊科成员,应单列一大熊猫科(Ailuropodidae)。在大熊猫种系进化中,它们的形态与机能是统一的。不同种类的形态特征,又是在适应环境中逐渐产生的。根据这个认识,我们把大熊猫的进化历程可划分为始发期、成长期、鼎盛期和衰败期。     

THE RELATIONSHIP BETWEEN EVOLUTIONARY BIOLOGY AND RELIGION

Belief in creationism and intelligent design is widespread and gaining significance in a number of countries. This article examines the characteristics of science and of religions and the possible relationship between science and religion. I argue that creationism is sometimes best seen not as a misconception but as a worldview. In such instances, the most to which a science educator (whether in school, college or university) can normally aspire is to ensure that students with creationist beliefs understand the scientific position. In the short term, the scientific worldview is unlikely to supplant a creationist one for students who are firm creationists. We can help students to find their evolutionary biology courses interesting and intellectually challenging without their being threatening. Effective teaching in this area can help students not only learn about the theory of evolution but better appreciate the way science is done, the procedures by which scientific knowledge accumulates, the limitations of science, and the ways in which scientific knowledge differs from other forms of knowledge.     

THE RELATIONSHIP BETWEEN EVOLUTIONARY THEORY AND PHYLOGENETIC ANALYSIS

The relationship between phylogenetic reconstruction and evolutionary theory is reassessed. It is argued here that phylogenies, and evolutionary principles, should be analysed initially as independently from each other as possible. Only then can they be used to test one another. If the phylogenies and evolutionary principles are totally consistent with one another, this consilience of independent lines of evidence increases confidence in both. If, however, there is a conflict, then one should assess the relative support for each hypothesis, and tentatively accept the more strongly supported one. We review examples where the phylogenetic hypothesis is preferred over the evolutionary principle, and vice versa, and instances where the conflict cannot be readily resolved. Because the analyses of pattern and process must initially be kept separate, the temporal order in which they are performed is unimportant. Therefore, the widespread methodology of always proceeding from cladogram to evolutionary ‘scenario’ cannot be justified philosophically. Such an approach means that cladograms cannot be properly tested against evolutionary principles, and that evolutionary ‘scenarios’ have no independent standing. Instead, we propose the ‘consilience’ approach where phylogenetic and evolutionary hypotheses are formulated independently from each other and then examined for agreement.     

秋茄幼苗的形态特征及其生物量

对秋茄一年生幼苗的主要形态指标及其生物量进行了测定。结果表明,株高,茎高,基径,根高,根长,叶面积以及胚,胚轴,茎,叶和全株生物量等计量指标,呈现算术平均值〉中值〉众值组段中点的规律,符合正偏态分布。     

澜沧舞花姜繁殖生物学特性及其进化意义探讨

 舞花姜属（Globba）植物具有多样的繁殖策略。分布于西双版纳的澜沧舞花姜（Globba lancangensis）自然条件下既能结实,同时又能在花序下部产生珠芽。通过对澜沧舞花姜的花部性状、花粉活力、传粉昆虫的访花行为、结实状况、珠芽产量等多方面的观测,初步了解了澜沧舞花姜的繁殖生物学特性。结果表明,澜沧舞花姜具有雄花及两性花同株的性表达特征。雄花及两性花的花粉在中午12∶00以前活力很高,之后雄花的花粉活力急剧下降,而两性花的花粉到16∶00仍有萌发能力。澜沧舞花姜在花序上产生雄花及两性花,每个花序每天仅开少量的花,其中50%的时间仅开雄花或两性花,在整个种群中形成了一定程度的暂时性的雄花两性花异株现象,从而增加了异交的可能性。澜沧舞花姜雄花的存在为P/O低的两性花提供了花粉补贴,这使得它可以通过调节雄花与两性花比例来调节种群的P/O,从而保证一定的结实能力。人工自交与异交下结果率没有差异,但自交结实率显著低于异交结实率,表明澜沧舞花姜有明显的自交不亲和现象。排蜂（Megapis dorstata）和黄绿彩带蜂（Nomia strigata）是澜沧舞花姜的主要访花昆虫,其中排蜂是它的有效传粉昆虫。澜沧舞花姜可能通过雄花两性花同株与自交不亲和相结合来促进异交。     

MITOCHONDRIAL GENE TREES AND THE EVOLUTIONARY RELATIONSHIP OF MALLARD AND BLACK DUCKS

We assayed restriction site differences in mitochondrial DNA (mtDNA) within and among allopatric populations of the Mallard (Anas platyrhynchos) and the American Black Duck (A. rubripes). The observed mtDNA clones grouped into two phylogenetically distinct arrays that we estimate differ by about 0.8% in nucleotide sequence. Genotypes in one clonal array were present in both species, while genotypes in the other array were seen only in Mallards. In terms of the mtDNA “gene tree,” the assayed Mallards exhibit a paraphyletic relationship with respect to Black Ducks, meaning that genealogical separations among some extant haplotypes in the Mallard predate the species separation. Evidence is advanced that this pattern probably resulted from demographically based processes of lineage sorting, rather than recent, secondary introgressive hybridization. However, haplotype frequencies were most similar among conspecific populations, so the Mallard and Black Ducks cluster separately in terms of a population phenogram. The results provide a clear example of the distinction between a gene tree and a population tree, and of the distinction between data analyses that view individuals versus populations as operational taxonomic units (OTUs). Overall, the mtDNA data indicate an extremely close evolutionary relationship between Mallards and Black Ducks, and in conjunction with the geographic distributions suggest that the Black Duck is a recent evolutionary derivative of a more broadly distributed Mallard-Black ancestor.