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1.
锦鸡儿属(Caragana)是一个温带亚洲分布属.在我们对这一属系统发育树以及13个分布区的基础上,重点采用Bremer(1992),Ronquist(1994)和Hausdorf(1997)提出的方法,进行本属祖先分布区的分析和探讨.结果表明,3种方法均表明远东-我国东北,阿尔泰-萨彦岭以及华北-秦岭是可能的祖先分布区.结合北温带植物类群属的北方起源学说,认为远东-我国东北为原始分布区的可能性更大一些.同时这三个分布区彼此地理上是隔离的,也恰是本属内一个较原始种树锦鸡儿(Caragana arborescens)的分布区,结合我们以前的分析生物地理学研究,认为隔离分化是本属最重要的物种形成方式,扩散是次要的而且是短距离的扩散.  相似文献   

2.
将锦鸡儿属(Caragana)植物分布区划分成13个。在分支系统学基础上,进行了分布区的成分分析。以种类和系为分布特征,进行分布区的聚类分析和最小生成树分析。分布区分支图、表征图和最小生成树从不同方面表达了分布区的关系。锦鸡儿属的分布区被分成东亚和古地中海两大部分。其中分别来自这两部分的前苏联远东-我国东北与阿尔泰-萨彦岭分布区有密切关系。基于分布区分支图,属的分布区分别由这两个分布区衍生,同时结合属的种系发生关系,推断本属可能起源于东西伯利亚,时间为第三纪中新世末-上新世。生态适应上,分类群是由东部温带中生性类型向西部旱化和寒化方向发展的。  相似文献   

3.
针对特有性简约性分析(PAE)不足之处,提出一个新的改进分析方法。主要区别是,新方法对分布区内分类群区分了原始和演化,相应地编码为0/1;为了获取分类群原始和演化的特性,分析以分类群分支图为基础。新方法是系统发育与地理分布相统一原理的一个具体的定量化探讨。用新方法分析了豆科锦鸡儿属锦鸡儿组15种,结果表明新方法优于以前的PAE方法。用新的改进方法分析得到的可能的祖先分布区是原始类群树锦鸡儿和一大类属内原始类群的分布区。与目前属的起源问题的一般观点相一致。  相似文献   

4.
锦鸡儿属分析生物地理学的研究   总被引:17,自引:0,他引:17  
将锦鸡儿属(Caragana)植物分布区划分成13个。在分支系统学基础上,进行了分布区的万分分析。以种类和系为分布特征,进行分布区的聚类分析和最小生成树分析。分布区分支图、表征图和最小生成树从不同方面表达了分布区的关系。锦鸡儿属的分布区被分成东亚和古地中海两大部分。其中分别来自这两部分的前苏联远东-我国东北与阿尔泰-萨彦岭分布区有密切关系。基于分布区分支图,属的分布区分别由这两个部分分布区衍生,同  相似文献   

5.
青藏高原和喜马拉雅地区锦鸡儿属植物的地理分布   总被引:9,自引:0,他引:9  
锦鸡儿属Caragana是一个典型的温带亚洲分布属。本属在青藏高原和喜马拉雅约有24种1变种,约占整个属的1/3。这些种类几乎全部处于演化高级阶段,且既有叶轴宿存类群,也有假掌状叶类群。反映出种的分化很活跃,在横断山地区形成本属的分布中心、分化中心。本区内绝大多数种类是特有分布。替代现象主要受气候、植被变化作用,沿横断山和喜马拉雅分布的长齿系Ser. Bracteolatae Kom.是一个典型的替代分布类群。锦鸡儿属植物生态适应性很强,可在其生长的灌丛中形成优势种。 寒化和旱化现象十分突出,它们有一系列森林种、草原种和荒漠种及相关的形态变异。用锦鸡儿属植物进行青藏高原和喜马拉雅区域内的分布区关系分析及最小生成树MST和特有性简约性分析(PAE),表明横断山地区特别是其北部是本属植物的一个地理结点。以此沿横断山向北部唐古特和西部藏东南适应性辐射。横断山和西喜马拉雅联系微弱,看不出植物长距离扩散的踪迹,大多是由于生态因子限制而产生的隔离。虽然本区不可能是锦鸡儿属的起源地,然而,通过本区与邻近地区的地理联系,可推测它们在我国适应性辐射方向是从东北向西南。结合豆科蝶形花亚科其它属化石记录及其分布区局限在温带亚洲等现象,认为锦鸡儿植物是一组特化、晚近衍生的类群,起源于北方东西伯利亚晚第三纪中新世后期至上新世。  相似文献   

6.
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   

7.
橐吾属的起源、演化与地理分布   总被引:20,自引:1,他引:19  
橐吾属Ligularia Cass.是菊科千里光族款冬亚族的一个大属。在款冬亚族中本属与大吾风草属 Farfugium Lindl.亲缘关系最近,但进化程度较高。本属包括6组,11系129种。所有种类均分布在 亚洲,仅2种扩散至欧洲。在东亚地区有119种,占该属总种数的96%。高度集中在横断山区的有4组、 6系67种,其中61种为特有种,占该属总组数的66%,总系数的54.5%,总种数的52%。这个事实 表明了横断山区是该属的多度中心和多样化中心。通过性状分析,伞房组伞房系Sect.Corymbosae, Ser.Calthifoliae叶肾形,具掌状叶脉,头状花序大而少,排列呈伞房状,总苞半球形,被认为是该属的 原始类群。原始种齿叶橐吾L. dentata和鹿蹄橐吾L.hodgsonii的分布区从我国四川东部经过湖北、湖 南、安徽、福建等省至日本。这个分布格局与近缘属大吴风草属Farfugium一致。 根据共同起源原理,这两个属的祖先极有可能就发生在这一地区。因此我们推测东亚地区从中国四 川东部至日本这一地区是本属的发源地,然而根据地质历史和现代分布,作者认为中国中部(包括四川 东部)是本属的初始起源地。该属起源后,基本上沿亚洲南缘的山地扩散,少数种类向东北至亚洲东北部。本属起源时间至少不晚于中白垩纪。  相似文献   

8.
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   

9.
榉属(Zelkova)是包含6个种的榆科小属, 呈东亚、西亚和南欧间断分布。该文基于DNA序列trnL-trnF和ITS构建了榉属的分子系统发育树, 大体上把此属分为3个分支, 分别对应东亚、西亚和南欧的种类, 与前人仅依据ITS序列的结果不同。生物地理的扩散和隔离分化分析(DIVA)表明, 榉属的原始祖先分布区可能是欧亚北温带, 包括了东亚、西亚和南欧的某个大的区域。分化过程以隔离分化为主要特征, 即3个分布区域是逐步隔离分化的。由于东亚的物种多样性, 北太平洋有可能是起源中心。榉属的现代分布格局可能主要是由于渐新世发生的古地中海西退、中新世发生的青藏高原大范围隆升, 以及第四纪冰川活动引起的分布区的收缩。  相似文献   

10.
地黄属分子系统学分析   总被引:4,自引:0,他引:4  
地黄属是中国准特有属,属内种间关系仍待澄清。该研究基于多个个体的叶绿体与核基因片段对地黄属进行系统发育重建,探讨属内物种分化与可能历史。结果表明:(1)地黄属为单系群,天目地黄为本属原始类群,并与湖北地黄互为姐妹群或连续姐妹群,裂叶地黄-高地黄、地黄-茄叶地黄分别组成姐妹群;(2)多个个体构建的系统树更能揭示本属物种关系的复杂性;(3)祖先分布区重建表明本属经历过3次扩张与2次隔离过程,物种形成过程与历史气候变化密切相关。最后该研究提出了地黄属物种形成研究亟待解决的几个重要问题。  相似文献   

11.
Ancestral Area Analysis of the Genus Caragara (Leguminosae)   总被引:1,自引:0,他引:1  
Caragana has a temperate Asian distribution. Based on the phylogeny and 13 distributionalareas of this genus, its ancestral area was studied via the ancestral area analysis suggested by Bremer(1992), Ronquist (1994) and Hausdorf (1997). The results indicate that three areas, Far East-NortheastChina, Altai-Sayan and North China-Qinling Mountains (Mts) are likely the ancestral areas. Linking to theviewpoints of the Holarctic origin for north temperate flora, Far East-Northeast China seems more likely tobe the ancestral area. According to the three ancestral areas isolated geographically and the analysis inthe present study, as well as former biogeographical analysis of this genus, it is suggested that Caraganaspeciation is mainly in the mode of vicariance rather than dispersal, and dispersed is often in shortdistance.  相似文献   

12.
Although the faunal elements of Far East Asian Mesozoic terrestrial biota have attracted much attention in recent years, their palaeoecology remains poorly known. In particular, features of the palaeoclimate are highly controversial. To address this point we used the Mesozoic fossil wood Xenoxylon , a genus recognized as an indicator of wet temperate biotopes and which is common in the area during the Carnian–Maastrichtian interval. We re-appraised bibliographic data and gathered new data for Xenoxylon in the Mesozoic of Far East Asia. This demonstrated that previous taxonomic approaches to the genus have been so far idiosyncratic. We examined the anatomical diversity of morphogenus Xenoxylon in Far East Asia and compared it to that of samples from Europe. This indicates that in an area centred on north-eastern China, Xenoxylon reached a level of anatomical diversity unmatched elsewhere in the world. We hypothesize that this diversity witnesses the persistence of palaeoecological conditions particularly suitable for Xenoxylon and that a wet temperate climate prevailed over most of the area throughout the Carnian–Maastrichtian interval. It is in this setting that the famous Jehol Biota probably evolved.  相似文献   

13.
槭树科的地理分布   总被引:35,自引:3,他引:35  
槭树科是北温带分布的科,2属202种。本文论述了本科的植物生态学、科的地理分布、槭属的亚属和组系统位置及其分布式样和种的分布,以及对古特有种、新特有种的分析,认为北温带分布的槭树科是热带起源的,其分布中心和祖型都在中国亚热带山地-横断山区连同湖北、湖南和四川东部。在这里,特别在横断山区槭树科种类丰富、分布集中,古特有和新特有成分均多,分化明显,是新老区的结合及分布中心,而且很有可能是槭树科的起源地  相似文献   

14.
This study compares results on reconstructing the ancestral state of characters and ancestral areas of distribution in Cornaceae to gain insights into the impact of using different analytical methods. Ancestral character state reconstructions were compared among three methods (parsimony, maximum likelihood, and stochastic character mapping) using MESQUITE and a full Bayesian method in BAYESTRAITS and inferences of ancestral area distribution were compared between the parsimony-based dispersal-vicariance analysis (DIVA) and a newly developed maximum likelihood (ML) method. Results indicated that among the six inflorescence and fruit characters examined, "perfect" binary characters (no homoplasy, no polymorphism within terminals, and no missing data) are little affected by choice of method, while homoplasious characters and missing data are sensitive to methods used. Ancestral areas at deep nodes of the phylogeny are substantially different between DIVA and ML and strikingly different between analyses including and excluding fossils at three deepest nodes. These results, while raising caution in making conclusions on trait evolution and historical biogeography using conventional methods, demonstrate a limitation in our current understanding of character evolution and biogeography. The biogeographic history favored by the ML analyses including fossils suggested the origin and early radiation of Cornus likely occurred in the late Cretaceous and earliest Tertiary in Europe and intercontinental disjunctions in three lineages involved movements across the North Atlantic Land Bridge (BLB) in the early and mid Tertiary. This result is congruent with the role of NALB for post-Eocene migration and in connecting tropical floras in North America and Africa, and in eastern Asia and South America. However, alternative hypotheses with an origin in eastern Asia and early Trans-Beringia migrations of the genus cannot be ruled out.  相似文献   

15.
This study compares results on reconstructing the ancestral state of characters and ancestral areas of distribution in Cornaceae to gain insights into the impact of using different analytical methods. Ancestral character state reconstructions were compared among three methods (parsimony, maximum likelihood, and stochastic character mapping) using MESQUITE and a full Bayesian method in BAYESTRAITS and inferences of ancestral area distribution were compared between the parsimony-based dispersal-vicariance analysis (DIVA) and a newly developed maximum likelihood (ML) method. Results indicated that among the six inflorescence and fruit char-acters examined, “perfect” binary characters (no homoplasy, no polymorphism within terminals, and no missing data) are little affected by choice of method, while homoplasious characters and missing data are sensitive to methods used. Ancestral areas at deep nodes of the phylogeny are substantially different between DIVA and ML and strikingly different between analyses including and excluding fossils at three deepest nodes. These results, while raising caution in making conclusions on trait evolution and historical biogeography using conventional methods, demonstrate a limitation in our current understanding of character evolution and biogeography. The biogeographic history favored by the ML analyses including fossils suggested the origin and early radiation of Cornus likely occurred in the late Cretaceous and earliest Tertiary in Europe and intercontinental disjunctions in three lineages involved movements across the North Atlantic Land Bridge (BLB) in the early and mid Tertiary. This result is congruent with the role of NALB for post-Eocene migration and in connecting tropical floras in North America and Africa, and in eastern Asia and South America. However, alternative hypotheses with an origin in eastern Asia and early Trans-Beringia migrations of the genus cannot be ruled out.  相似文献   

16.
Establishing the ancestral area of a group of organisms is one of the central objectives of historical biogeography. I applied three methods of ancestral area analysis, Fitch optimization, weighted ancestral area analysis and dispersal-vicariance analysis (DIVA) to establish the ancestral area of the iguanian lizard genus Phymaturus . I then extended the analysis to hypothesize the ancestral area for Liolaemidae ( Ctenoblepharys , Liolaemus and Phymaturus ). The ancestral area for Phymaturus is Patagonia Central or Patagonia Central-Cordillera Andina and Valle Central. For Liolaemidae, the ancestral area is Patagonia Central-Coastal Perú, or Patagonia Central-Patagonia Occidental-Cordillera Andina and Valle Central-Coastal Perú. The ancestral area of Phymaturus is congruent with previous studies, but the inclusion of Ctenoblepharys poses some questions regarding the distribution of the ancestor of the family.  相似文献   

17.
Biogeographic patterns and the evolution of eureptantic nemerteans   总被引:1,自引:0,他引:1  
The origin and evolution of the eureptantic nemerteans is discussed from a biogeographic point of view. It is most likely that East Indian Ocean was part of the ancestral distribution of the Eureptantia. The area cladogram estimated by Brooks parsimony analysis (BPA) is to a high degree congruent with a vicariance explanation of the evolution of the Eureptantia and suggests an ancestral distribution concordant with the Tethys Sea. A general area cladogram based on a combined BPA analysis of eureptantic nemerteans and acanthuroid fishes is reconstructed and suggested as a hypothesis of the relationships between east Indian Ocean, west Indian Ocean, west Pacific Ocean, east Adantic Ocean, west Atlantic Ocean, and the Mediterranean. This tree is compared with cladograms from the same areas based on other taxa.  相似文献   

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