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1.
应用HENNIG86系统发生分析程序,选择出成虫的有代表性的16个共同衍征,分析了与康蚖属相关各属的各个种类,得出了该类群的相关系统树。同时对特征的演化以及其扩散途径等也进行了讨论。文中还应用Page 1993的COMPONENT程序进行了生物地理学的分析;得到种类—地区支序图。其中康蚖属表现为典型的印度—太平洋分布型,而其姐妹群新康蚖属则兼有东洋区和全北区的分布型。至于分布地区的相互关系和在这些地区的分衍替代事件的发生等问题也作了初步的假想。  相似文献   

2.
Approaches using phylogenetic pattern in ecological communities to deduce processes of community assembly have been criticised as disconnected from foundations in ecological mechanism, especially with respect to lack of data about abiotic and biotic niches. These criticisms can be addressed with analyses of organismal traits that underlie environmental filtering, competitive exclusion, and other candidate processes; however, the difficulty of assembling large trait databases means that such studies remain uncommon. We suggest a synthesis of phylogenetic community structure analysis and species distribution modeling that we believe can allow inference about community processes without prohibitive data requirements. We illustrate this method for angiosperm communities of rock barrens in eastern Canada. First, we analyzed phylogenetic community structure of four rock‐barren sites at three nested spatial scales (quadrat to region). For the nine most common species in our barrens, we used regional occurrence records to build species distribution models identifying environmental drivers of the nine species’ distributions. Coefficients of these models represent implicit trait data that summarize each species’ response to the environmental drivers in the model. We then tested for phylogenetic signal in these traits, to ask whether ecological forces acting on them could be generating phylogenetic community structure. We found strong phylogenetic clustering at the quadrat level, while patterns at larger scales were complex. Our distribution model suggested drought stress as the dominant driver for distributions of all the species, consistent with local correlations with soil depth, and the species’ responses to drought showed strong phylogenetic signal. The convergence of results from phylogenetic community structure and species distribution modeling suggests that barren communities are structured at the quadrat level by environmental filtering effects of moisture stress, to which species have phylogenetically patterned responses.  相似文献   

3.
The frequency distribution of numbers of species in taxonomic groups, where many species belong to a few very diverse higher taxa, is mirrored by that of species in most communities, where many individuals belong to a few very abundant species. Various hypotheses mechanistically link a species' community abundance with the diversity of the higher level taxon (genus, family, order) to which it belongs, but empirical data are equivocal about general trends in the relation between rank-taxon diversity and mean abundance. One reason for this inconclusive result may be the effect of the semisubjective nature of rank-based classification. We assessed the relationship between clade diversity and mean species abundance for two diverse tropical tree communities, using both traditional rank-based analysis and two new phylogenetic analyses (based on the ratio of individuals to taxa at each node in the phylogeny). Both rank-based and phylogenetic analyses using taxonomic ranks above the species level as terminal taxa detected a trend associating common species with species-rich families. In contrast, phylogenetic analyses using species as terminal taxa could not distinguish the observed distribution of species abundances from a random distribution with respect to clade diversity. The difference between these results might be due to (1) the absence of a real phylogeny-wide relationship between clade abundance and diversity, (2) the influence of poor phylogenetic resolution within families in our phylogenies, or (3) insufficient sensitivity of our metrics to subtle tree-wide effects. Further development and application of phylogeny-based methods for testing abundance-diversity relationships is needed.  相似文献   

4.
毛茛科是真双子叶植物的基部类群之一, 包含多种药用植物, 具有较高的保护价值, 但关于毛茛科物种多样性和谱系多样性大尺度格局及其影响因子的研究还比较匮乏, 特别是以较高分辨率分布数据为基础的物种多样性格局研究尚未见报道。本文旨在: (1)建立欧亚大陆东部毛茛科植物分布数据库, 估算不同生活型物种多样性和谱系多样性格局, 并探究格局的形成机制。(2)分析毛茛科物种多样性和谱系多样性的相关关系, 确定多样性热点地区, 为毛茛科保护规划提供依据。根据中国、哈萨克斯坦、吉尔吉斯斯坦、塔吉克斯坦、土库曼斯坦、乌兹别克斯坦、蒙古和俄罗斯等国家的区域和地方植物志, 建立了“欧亚大陆东部地区毛茛科物种分布数据库”。该数据库包含了欧亚大陆东部地区1,688种毛茛科物种的分布数据, 空间分辨率为100 km × 100 km。在此基础上, 估算了毛茛科全部及不同生活型的物种多样性和谱系多样性格局, 并利用广义线性模型和等级方差分离方法分析了毛茛科物种和谱系多样性格局与环境因子的关系。最后比较了物种多样性和谱系多样性的相关关系, 确定了毛茛科的古热点地区。结果显示: (1)欧亚大陆东部毛茛科植物物种和谱系多样性均呈明显的纬度格局, 且在山区具有较高的多样性。(2)毛茛科植物物种和谱系多样性受现代气候、地形异质性和末次冰期以来的气候变化的共同影响, 但不同影响因子的相对贡献率在物种和谱系多样性及不同生活型之间差异显著。(3)中高纬度地区的谱系多样性高于给定物种数的预期, 是毛茛科的古热点地区, 在毛茛科保护规划中应受到重视。  相似文献   

5.
A method is proposed to conduct phylogenetic analyses of comparative or interspecific data when the true phylogeny is not known. Standard models of speciation and/or extinction or other methods are used to generate a sample from the set of all possible phylogenies for the measured species. The comparative data are then analyzed on each of the possible trees to obtain a distribution of possible evolutionary statistics for these data. The mean of this distribution is proposed as a reasonable estimate of the true evolutionary statistic of interest. Ways of obtaining confidence intervals and of developing hypothesis tests for this mean statistic are also proposed. The method can be used with any comparative method or phylogenetic analysis technique when phylogenetic relationships among species are not known or when branch lengths for a phylogeny in units of expected character change (as required by most methods) are not available. Computer programs to conduct the analyses are available on request.  相似文献   

6.
The evolution of a particular trait or combination of traits within lineages may affect subsequent evolutionary outcomes, leading closely related species to exhibit higher phenotypic similarity than expected under a simple Brownian‐motion evolutionary model. Niche theory postulates that phenotypes determine species distribution across environmental gradients, leading to a phylogenetic signature in the community assembly. Thus, the incorporation of species phylogeny in the analysis of community ecology structure allows one to link broader environmental, spatial and temporal factors to local, small‐scale ecological processes, thus enabling understanding of community assembly patterns in a broader context. We used the net relatedness index to assess phylogenetic structure within avian communities across a harshness gradient in coastal habitats in southern Brazil. We also evaluated phylogenetic beta diversity, to test whether closely related species exploit habitats with similar environmental conditions. In order to do so, we scaled up phylogenetic information from the species to site level using phylogenetic fuzzy weighting. We found a pattern of phylogenetic clustering in less‐vegetated habitats, namely sandy beach and dunes, which are subject to harsher conditions because of proximity to the ocean. Basal lineages were associated with the more structurally homogeneous sandy beach, while late‐divergence clades occurred in more complex habitats, which were positively related to vegetation cover and height. The observed pattern of phylogenetic clustering suggested the importance of harsh conditions in constraining the distribution of avian lineages. Furthermore, contrasting environmental features between habitats influenced phylogenetic variation, demonstrating the prevalence of phylogenetic habitat filtering. From an applied point of view, such as planning and management of biological reserves, we showed that the full array of habitat patches embedded within coastal ecological gradients must be included in order to preserve distinct evolutionary lineages.  相似文献   

7.
We have presented a formal model for the quantitative analysis of phylogenetic and specific effects on the distribution of trait values among species. Total trait values are divided into phylogenetic values, inherited from an ancestral species, and specific values, the result of independent evolution. This allows a quantitative assessment of the strength of the phylogenetic inertia, or burden, displayed by a character in a lineage, so that questions concerning the relative importance of phylogenetic constraints in evolution can be answered. The separation of phylogenetic from specific effects proposed here also allows phylogenetic factors to be explicitly included in cross-species comparative analyses of adaptation. This solves a long-standing problem in evolutionary comparative studies. Only species' specific values can provide information concerning the independent evolution of characters in a set of related species. Therefore, only correlations among specific values for traits may be used as evidence for adaptation in cross-species comparative analyses. The phylogenetic autocorrelation model was applied to a comparative analysis of the determinants of sexual dimorphism in weight among 44 primate species. In addition to sexual dimorphism in weight, mating system, habitat, diet, and size (weight itself) were included in the analysis. All of the traits, except diet, were substantially influenced by phylogenetic inertia. The comparative analysis of the determinants of sexual dimorphism in weight indicates that 50% of the variation among primate species is due to phylogeny. Size, or scaling, could account for a total of 36% of the variance, making it almost as important as phylogeny in determining the level of dimorphism displayed by a species. Habitat, mating system, and diet follow, accounting for minor amounts of variation. Thus, in attempting to explain why a particular modern primate species is very dimorphic compared to other primates, we would say first because its ancestor was more dimorphic than average, second because it is a relatively large species, and third because it is terrestrial, polygynous, and folivorous.  相似文献   

8.
啮齿动物分子系统地理学研究进展   总被引:2,自引:1,他引:1  
系统地理学是研究种间及种内不同种群的形成、现有分布格局的历史原因和演化过程的一门学科。基于分子水平,能够更准确地界定物种分布格局,促进分子系统地理学的形成和发展。近年来,分子系统地理研究的开展,促进了对啮齿动物物种分布格局形成机制的理解。对啮齿动物的种内及种上分类阶元的系统演化关系、起源中心与演化历程、影响系统地理格局的因素、鼠害防控和保护生物学等分子系统地理学方面的研究进行了综述。并提出了啮齿动物分子系统地理学未来发展的四点展望:1)综合性系统地理学研究;2)区域系统地理学研究;3)物种演化的全面系统研究;4)新型分子标记和分析方法的发展。  相似文献   

9.
Characters of scale surface microstructure are combined with 'traditional'morphological characters in a phylogenetic analysis of the Tropidurini. Tropidurid lizards show variation in types of coarse and fine scale surface microstructure, in the anatomical distribution of different scale surface features, and in scale organ morphology and distribution. The morphology of the inner surface zone of scales is here described for the first time using scanning electron microscopy. Our phylogeny differs considerably from those proposed in earlier studies. New characters and frequency coding of polymorphic characters help resolve the problematic relationships of several species. Statistical confidence supports recognition of one large cis-Andean and one large trans-Andean clade of species. Based on our results, we synonymize Plesiomicrolophus with Microlophus and Uranoscodon with Tropidurus. The phylogenetic relationships of newly discovered Tropidurus are resolved: T. caltathelys is the sister species of T. melanopleurus; T. xanthochilus is the sister species of T. spinulosus. Tropidurus spinulosus is found to be more closely related to T. strobilurus and a clade of Amazonian species than to T. melanopleurus. The species previously placed in Uracentron are more closely related to species previously placed in Plica than to 77 strobilurus as previously thought.  相似文献   

10.
The distribution of freshwater taxa is a good biogeographic model to study pattern and process of vicariance and dispersal. The subfamily Leuciscinae (Cyprinidae, Teleostei) consists of many species distributed widely in Eurasia and North America. Leuciscinae have been divided into two phyletic groups, leuciscin and phoxinin. The phylogenetic relationships between major clades within the subfamily are poorly understood, largely because of the overwhelming diversity of the group. The origin of the Far Eastern phoxinin is an interesting question regarding the evolutionary history of Leuciscinae. Here we present phylogenetic analysis of 31 species of Leuciscinae and outgroups based on complete mitochondrial genome sequences to clarify the phylogenetic relationships and to infer the evolutionary history of the subfamily.  相似文献   

11.
Graham Bell 《Oikos》2013,122(9):1380-1392
The ecological attributes of two species may be similar through convergent evolution or common ancestry. The extent of similarity by descent can be evaluated by comparing them with their most closely‐related outgroup in a given phylogeny. I describe a method of nested sister‐group analysis for estimating ecological similarity based on landscape features or on co‐distribution. The phylogeny is dissected into triplets, each comprising two sister taxa and their outgroup. For a triplet at any phylogenetic level, the similarity of sister groups with respect to some given character can be compared with their joint similarity to the outgroup to give a single test of similarity by descent. Each comparison is independent, and the full set of triplets provides a complete accounting of phylogenetic variation at all levels. This procedure was applied to 188 moderately abundant species of dicots in two independent surveys from adjoining districts of midland England, supplemented by physical surveys of landscape attributes obtained from digitized maps of the same districts. The co‐distribution of sister species was consistently more positive than the co‐distribution of random species pairs, demonstrating the existence of a phylogenetic signal at some level. When sister species are compared with their most closely‐related outgroup, however, neither landscape attributes nor co‐distribution showed any overall similarity arising from common ancestry, in the sense that ecological attributes are not generally conserved after lineage splitting. Instead, the distribution of similarity is strikingly similar to random data. The lack of ecological similarity between closely‐related groups was attributed to rapid character change at or shortly after the splitting of lineages, coupled with a lack of correlation between successive lineage splits.  相似文献   

12.
A new phylogenetic hypothesis for the living species of triplespine fishes of the Indo-Western Pacific family Triacanthidae (Tetraodontiformes, Teleostei) is proposed. A data set of 55 morphological characters (34 osteological and 21 morphometric) was constructed. A cladistic analysis of the osteological data set yielded a single most-parsimonious tree. This cladogram does not support the monophyly of one of the four genera, Tripodichthys , but Bremer values for this analysis are low. The osteological data set was then combined with a data set of 21 morphometric characters that had previously been used to diagnose the four genera. The analysis of the combined data set produced the same phylogenetic hypothesis, but with greater nodal support. The biogeographical distribution of the living species is then interpreted with the use of this new phylogenetic information.  相似文献   

13.
蚊科的区系分布及其演变的初步探讨:双翅目:蚊科   总被引:4,自引:0,他引:4  
  相似文献   

14.
The identification of priority areas and species for conservation is an urgent endeavor in view of environmental changes threatening biological diversity. New macroecological tools that take advantage of the rapid accumulation of distribution and phylogenetic data have been developed recently to tackle that challenge. Here we use the novel concept of the diversity and dispersion fields, complemented with phylogenetic information, to identify priorities for the conservation of neotropical glass frogs (Centrolenidae), both from the perspective of sites and of species. Through the novel approach used here, the priority level of species and sites could be determined by combinations of different traits based both on diversity (species richness and phylogenetic diversity) and distribution (geographic rarity and phylogenetic endemism). Patterns of diversity and distribution for Centrolenidae, such as extreme level of restrictedness, high levels of rarity and high segregation among species, were readily revealed by the use of range-diversity plots. Results were in some cases consistent with studies based on traditional analyses, but the inclusion of phylogenetic information added a historical-evolutionary perspective that further enhanced the analyses. We identified priority species (such as Rulyrana susatamai and Nymphargus griffithsi) and sites (such as the Guiana Shield) that harbor the evolutionary history of the group but that had been overlooked in prior studies. We suggest that for priority setting and gap analysis, phylogenetic information should not be treated as a full substitute for traditional measures of diversity but as a complementary tool.  相似文献   

15.
生物多样性的海拔分布格局是生态学研究的热点。海拔作为综合性因子驱动着植物群落的物种、系统发育与功能多样性的空间分布。以戴云山南坡900-1600 m森林植物群落为研究对象,探讨物种多样性、系统发育指数与环境驱动因子的相互关系以及环境因子在群落构建与多样性维持中的重要意义。结果表明:(1)森林植物群落的系统发育多样性与物种多样性沿海拔均呈现中间高度膨胀格局。(2)物种多样性Margalef指数、Shannon-Wiener指数与系统发育多样性指数呈显著正相关,表明物种多样性越高,系统发育多样性也越高。Shannon-Wiener指数与物种多样性指数(Margalef、Pielou、Simpson指数)、系统发育多样性及系统发育结构都存在显著相关性,一定程度上Shannon-Wiener指数可以代替其他指数。Pielou指数、Simpson指数、Shannon-Wiener指数与系统发育结构NRI (Net relatedness index)指数、NTI (Net nearest taxa index)指数存在显著正相关,表明群落优势度、均匀度与系统发育结构相关性较强。(3)土壤全磷含量是影响系统发育多样性和物种多样性的主要驱动因子,土壤含水量是影响Shannon-Wiener、Pielou、Simpson指数的最显著因子,海拔是影响群落系统发育结构的主要因素。海拔是影响系统发育结构变化的主要环境因子,而土壤因子是影响物种多样性与系统发育多样性的主要因素,进一步验证了物种多样性与系统发育多样性的高度相关,结果旨在揭示物种群落空间分布规律。  相似文献   

16.
Tanacetum joharchii Sonboli & Kazempour Osaloo sp. nov. (Asteraceae–Anthemideae) is described and illustrated from the Khorasan province, northeast Iran. Tanacetum joharchii is a suffruticulose species from rocky limestone mountains in Hezarmasjed and Binalud (Khorasan province) at altitudes of 1900–2500 m a.s.l. The diagnostic morphological characteristics that distinguish it from the allied species T. kotschyi are presented. In addition, a distribution map of T. joharchii and the related species is given. In order to provide some hypothesis on its phylogenetic position, a molecular phylogenetic analysis based on nrDNA ITS sequence data of 14 representatives of the genus Tanacetum was performed.  相似文献   

17.
The six species and three subspecies in the genus Chimarrogale (Soricomorpha: Soricidae) are commonly referred to as Asiatic water shrews. The Chimarrogale are the most widely distributed group of Nectogaline shrews, extending throughout the Oriental region and Japan. Because of the limited numbers of specimens available for study, the phylogenetic relationships and biogeographical history of this genus have not been comprehensively discussed. We used mitochondrial cytochrome b gene sequences to estimate phylogenetic relationships and divergence times among four Chimarrogale species, including all three subspecies of Chimarrogale himalayica. We also conducted a species delimitation analysis and tested two alternative migration scenarios in Asia through species distribution modeling and a reconstruction of the ancestral distribution. Here, we present the first proposed hypothesis regarding the Asiatic water shrew phylogeny and reveal ten putative species within the four recognized species. Distinct phylogenetic statuses of Chimarrogale phaeura, Chimarrogale platycephala, and Chimarrogale styani were confirmed. Chimarrogale himalayica was strongly supported as paraphyletic. We suggest that three subspecies of Chimarrogale himalayica should be reconsidered as distinct species. However, these suggestions must be considered with caution because only a single locus of a mtDNA gene was used. Four additional putative species, possibly distributed in central southwestern China and Taiwan, are currently undescribed; therefore, comprehensive morphological analyses are warranted to test their taxonomic statuses. The estimated molecular divergence times indicated that rapid speciation occurred during the early Pliocene, and current distribution patterns may have been affected by global cooling during the Pliocene/Pleistocene boundary. Reconstruction of the ancestral distribution and species distribution modeling for Asiatic water shrews revealed a low-latitude migration route over which ancestral Chimarrogale migrated from Europe via Central Asia to their current distribution. Our results demonstrated that Asiatic water shrews could have evolved throughout the low-latitude migration route from Europe to East and Southeast Asia.  相似文献   

18.
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   

19.
对针叶树散斑壳Lophodermium conigenum与其近似种南方散斑壳L.australe的形态学特征及生态习性等进行了比较研究,同时对这两个种8个菌株的rDNA-ITS区进行了PCR扩增和序列测定,结合GenBank中16个相关ITS序列构建了系统发育树。结果表明,L.conigenum与L.australe有着非常密切的关系。L.conigenum除子囊果形状、子座基部层、线纹和寄生性外,其余特征与L.australe基本相同。L.conigenum的ITS序列的G+C含量(51.0%)小于L.australe的G+C含量(54.0%)。在系统发育树中,此二种形成两个明显独立的分支,支持了依据形态学等表型性状的分类。二者种间及种内的遗传差异与寄主有较大的相关性,而与产地无明显关联。通过表型性状和ITS序列的分析与比较,可准确地将L.conigenum与L.australe鉴别开来。  相似文献   

20.
Evidence of phylogenetic conservatism in plant ecological traits has accumulated over the past few years, suggesting an interplay between the distribution of phylogenetic clades and major environmental gradients. Nonetheless, determining what environmental factors underlie the distribution of phylogenetic lineages remains a challenge because environmental factors are correlated with spatial gradients where the latter might indicate some degree of dispersal limitation in phylogenetic pools. We analyzed the phylogenetic structure of plant assemblages across the Brazilian Araucaria forests and assessed how phylogenetic structure responds to environmental and spatial gradients. We compiled data on plant occurrence in 45 plots across the Araucaria forest biome. The phylogenetic structure of the plots was characterized using phylogenetic fuzzy‐weighting followed by principal coordinates of phylogenetic structure (PCPS). We used distance‐based redundancy analysis (db‐RDA) to analyze the relationships between phylogenetic clades and environmental and spatial factors. Variation partitioning showed that the phylogenetic structure of Brazilian Araucaria forests was better explained by environment factors (altitude and annual mean temperature) than by space. Yet, spatially‐structured environmental variation explained about one‐third of total variation in the phylogenetic structure. Thus, the influence of spatial filters on the phylogenetic structure was more related to environmental gradients across the Brazilian Araucaria forest biome than to dispersal limitation of phylogenetic lineages. Furthermore, the influence of explanatory factors on the phylogenetic structure was concentrated in few nodes, the one splitting tree ferns from seed plants, and a second splitting malvids from other eurosids. Assessing the functional links between species distribution patterns and environmental gradients is not an easy task when we have to deal with large species pools. Identifying major phylogenetic gradients across an environmental and/or geographical range of interest can represent a first step towards a better understanding of general assembly processes in ecological communities.  相似文献   

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