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1.
Rosidae, a clade of approximately 90 000 species of angiosperms, exhibits remarkable morphological diversity and extraordinary heterogeneity in habitats and life forms. Resolving phylogenetic relationships within Rosidae has been difficult, in large part due to nested radiations and the enormous size of the clade. Current estimates of phylogeny contain areas of poor resolution and/or support, and there have been few attempts to synthesize the available data into a comprehensive view of Rosidae phylogeny. We aim to improve understanding of the phylogeny of Rosidae with a dense sampling scheme using both newly generated sequences and data from GenBank of the chloroplast rbcL, atpB, and matK genes and the mitochondrial matR gene. We combined sequences from 9300 species, representing 2775 genera, 138 families, and 17 orders into a supermatrix. Although 59.26% of the cells in the supermatrix have no data, our results generally agree with previous estimates of Rosidae phylogeny and provide greater resolution and support in several areas of the topology. Several noteworthy phylogenetic relationships are recovered, including some novel relationships. Two families (Euphorbiaceae and Salvadoraceae) and 467 genera are recovered as non-monophyletic in our sampling, suggesting the need for future systematic studies of these groups. Our study shows the value of a botanically informed bioinformatics approach and dense taxonomic sampling for resolving rosid relationships. The resulting tree provides a starting point for large-scale analyses of the evolutionary patterns within Rosidae.  相似文献   

2.
We investigated the phylogeny of butterflies in the tribe Nymphalini sensu Harvey 1991, comprising the genera Vanessa, Cynthia, Bassaris, Aglais, Inachis, Nymphalis, Polygonia, Kaniska, Antanartia, Hypanartia, Symbrenthia, Mynes and Araschnia . Evidence from the mitochondrial gene ndl, the nuclear gene 'wingless' and from morphology/ ecology/behaviour were used separately and combined to analyse relationships. Phylogenies based on the different types of data agreed in many aspects of basic topology. We show that an analysis of only wing pattern characters (based on Nijhout's homology system) results in a topology broadly similar to the one resulting from analysis of the complete matrix. We found support for a monophyletic Nymphalini, where Hypanartia may be the sister clade to all other genera. Mynes, Symbrenthia and Araschnia together seem to form another basal clade. Evidence presented gives only moderate support for a monophyletic Vanessa in the wide sense, including also Cynthia and Bassaris , but strong support for the monophyly of the largely holarctic clade Aglais + Inachis + Nymphalis + Polygonia + Kaniska + Roddia . Within the latter group there is strong support for a clade consisting of Aglais + Inachis and for a second clade which includes Nymphalis, Polygonia (and its sister clade, the monotypic Kaniska) as well as Roddia l-album (= Nymphalis vaualbum ). As a consequence of this topology, Aglais is recognized as a taxon separate from Nymphalis . We present a hypothesis of species relationships within the focal group of genera. We also analyse and discuss the implications of excluding or including ecological data in phylogenetic tree construction, when the tree is to be used for studies in phylogenetic ecology.  相似文献   

3.
We reconstructed a phylogenetic tree of Chinese vascular plants (Tracheophyta) using sequences of the chloroplast genes atpB, matK, ndhF, and rbcL and mitochondrial matR. We produced a matrix comprising 6098 species and including 13?695 DNA sequences, of which 1803 were newly generated. Our taxonomic sampling spanned 3114 genera representing 323 families of Chinese vascular plants, covering more than 93% of all genera known from China. The comprehensive large phylogeny supports most relationships among and within families recognized by recent molecular phylogenetic studies for lycophytes, ferns (monilophytes), gymnosperms, and angiosperms. For angiosperms, most families in Angiosperm Phylogeny Group IV are supported as monophyletic, except for a paraphyletic Dipterocarpaceae and Santalaceae. The infrafamilial relationships of several large families and monophyly of some large genera are well supported by our dense taxonomic sampling. Our results showed that two species of Eberhardtia are sister to a clade formed by all other taxa of Sapotaceae, except Sarcosperma. We have made our phylogeny of Chinese vascular plants publically available for the creation of subtrees via SoTree (http://www.darwintree.cn/flora/index.shtml), an automated phylogeny assembly tool for ecologists.  相似文献   

4.
Large‐scale phylogenies provide a framework for interdisciplinary investigations in taxonomy, evolutionary biology, biogeography, ecology, and conservation. Integration of regional tree of life and species distribution data has greatly promoted spatial phylogenetic studies on biodiversity, floristic assembly, and biogeographic regionalization. In this study, we updated the phylogenetic tree of Chinese vascular plants by integrating data from public databases and sequences newly generated by our laboratory, to facilitate the exploration of floristic and ecological questions at a country scale. A phylogenetic tree with 15 092 tips and 14 878 species was obtained, including 13 663 species (44.0%) and 2953 genera (95.7%) native to China. Only two families (Corsiaceae and Mitrastemonaceae) and 133 genera native to China are not sampled in this study. Low proportion of sampling is detected in orders with high species diversity and those with low species diversity. The Hengduan Mountains, plus the western Qinghai–Tibet Plateau and western Xinjiang, show the greatest gap of target molecular data for angiosperms. Our phylogeny of Chinese vascular plants recovers relationships among and within major lineages that are highly congruent with published phylogenies at a broader scale. Most families (98.7%) are supported as monophyletic, and 573 genera (17.9%) are recognized as non‐monophyletic. Finally, hotspots of phylogenetic diversity for the Chinese angiosperms at both the genus and species levels are identified based on our phylogram, implicating conservation priorities for phylogenetic diversity. The updated phylogeny of Chinese vascular plants is publically available to generate subtrees through our automated phylogeny assembly tool SoTree in the DarwinTree platform ( http://www.darwintree.cn/flora-sotree-v2/index.shtml ).  相似文献   

5.
Despite their abundance and ecological importance in a wide variety of shallow and deep water marine communities, octocorals (soft corals, sea fans, and sea pens) are a group whose taxonomy and phylogenetic relationships remain poorly known and little studied. The group is currently divided into three orders (O: Alcyonacea, Pennatulacea, and Helioporacea); the large O. Alcyonacea (soft corals and sea fans) is further subdivided into six sub-ordinal groups on the basis of skeletal composition and colony growth form. We used 1429bp of two mitochondrial protein-coding genes, ND2 and msh1, to construct a phylogeny for 103 octocoral genera representing 28 families. In agreement with a previous 18S rDNA phylogeny, our results support a division of Octocorallia into two major clades plus a third, minor clade. We found one large clade (Holaxonia-Alcyoniina) comprising the sea fan sub-order Holaxonia and the majority of soft corals, and a second clade (Calcaxonia-Pennatulacea) comprising sea pens (O. Pennatulacea) and the sea fan sub-order Calcaxonia. Taxa belonging to the sea fan group Scleraxonia and the soft coral family Alcyoniidae were divided among the Holaxonia-Alcyoniina clade and a third, small clade (Anthomastus-Corallium) whose relationship to the two major clades was unresolved. In contrast to the previous studies, we found sea pens to be monophyletic but nested within Calcaxonia; our analyses support the sea fan family Ellisellidae as the sister taxon to the sea pens. We are unable to reject the hypothesis that the calcaxonian and holaxonian skeletal axes each arose once and suggest that the skeletal axis of sea pens is derived from that of Calcaxonia. Topology tests rejected the monophyly of sub-ordinal groups Alcyoniina, Scleraxonia, and Stolonifera, as well as 9 of 14 families for which we sampled multiple genera. The much broader taxon sampling and better phylogenetic resolution afforded by our study relative to the previous efforts greatly clarify the relationships among families and sub-ordinal groups within each of the major clades. The failure of these mitochondrial genes as well as previous 18S rDNA studies to resolve many of the deeper nodes within the tree (including its root) suggest that octocorals underwent a rapid radiation and that large amounts of sequence data will be required in order to resolve the basal relationships within the clade.  相似文献   

6.
We analyzed sequence data of the 18S rDNA gene from representatives of nine mycoparasitic or zooparasitic genera to infer the phylogenetic relationships of these fungi within the Zygomycota. Phylogenetic analyses identified a novel monophyletic clade consisting of the Zoopagales, Kickxellales, Spiromyces, and Harpellales. Analyses also identified a monophyletic mycoparasitic-zooparasitic Zoopagales clade in which Syncephalis, Thamnocephalis, and Rhopalomyces form a sister group to a Piptocephalis-Kuzuhaea clade. Although monophyly of the mycoparasitic Dimargaritales received strong bootstrap and decay index support, phylogenetic relationships of this order could not be resolved because of the unusually high rate of base substitutions within the 18S rDNA gene. Overall, the 18S gene tree topology is weak, as reflected by low bootstrap and decay index support for virtually all internal nodes uniting ordinal and superordinal taxa. Nevertheless, the 18S rDNA phylogeny is mostly consistent with traditional phenotypic-based classification schemes of the Fungi.  相似文献   

7.
Previous phylogenetic analyses of the tribe Phyllotini, one of the largest components of the subfamily Sigmodontinae, have been based on a single source of evidence. In particular, morphological analyses were largely based on craniodental data, almost neglecting the potential phylogenetic information present in the postcranium. Despite the significant advances made in relation to the knowledge of phyllotine phylogeny in recent times, there are several unsolved issues that highlight the importance of a phylogenetic analysis that integrates multiple sources of evidence, including previously considered sources as well as new sources of data. We present here the first combined phylogenetic analysis (morphological and molecular) of phyllotines, which includes the widest taxon and character sampling to date. Our dataset includes 164 morphological characters, of which 83 are postcranial characters, plus 3561 molecular characters, scored for 52 species from 34 genera of Oryzomyalia. In this study 75 postcranial characters not previously considered in this group are thoroughly described, and their utility for solving the relationships within Phyllotini is evaluated by means of different complementary analyses. Phyllotini was retrieved as a monophyletic clade in the combined analysis, with a composition that matches that obtained in most other recent analyses. All genera of phyllotines were monophyletic and show high support values. Abrotrichini, Akodontini and Oryzomyini were also monophyletic. The inclusion of postcranial data appears to be of limited utility to solve the phylogenetic relationships within Phyllotini.  相似文献   

8.
Peintner U  Moncalvo JM  Vilgalys R 《Mycologia》2004,96(5):1042-1058
Research on the molecular systematics of Cortinarius, a species-rich mushroom genus with nearly global distribution, is just beginning. The present study explores infrageneric relationships using rDNA ITS and LSU sequence data. One large dataset of 132 rDNA ITS sequences and one combined da-taset with 54 rDNA ITS and LSU sequences were generated. Hebeloma was used as outgroup. Bayesian analyses and maximum-likelihood (ML) analyses were carried out. Bayesian phylogenetic inference performed equally well or better than ML, especially in large datasets. The phylogenetic analysis of the combined dataset with species representing all currently recognized subgenera recovered seven well-supported clades (Bayesian posterior probabilities BPP > 90%). These major clades are: /Myxacium s.l., /subg. Cortinarius, the /phlegmacioid clade (including the subclades /Phlegmacium and /Delibuti), the /calochroid clade (/Calochroi, /Ochroleuci and /Allutus), the /telamonioid clade (/Telamonia, /Orellani, /Anomali), /Dermocybe s.l. and /Myxotelamonia. Our results show that Cortinarius consists of many lineages, but the relationships among these clades could not be elucidated. On one hand, the low divergence in rDNA sequences can be held responsible for this; on the other hand, taxon sampling is problematic in Cortinarius phylogeny. Because of the incredibly high diversity (~2000 Cortinarius species), our sampling included <5% of the known species. By choosing type species of subgenera and sections, our sampling is strongly biased toward Northern Hemisphere taxa. More extensive taxon sampling, especially of species from the Southern Hemisphere, is essential to resolve the phylogeny of this important genus of ectomycorrhizal fungi.  相似文献   

9.
Blue‐tailed skinks (genus Plestiodon) are a common component of the terrestrial herpetofauna throughout their range in eastern Eurasia and North and Middle America. Plestiodon species are also frequent subjects of ecological and evolutionary research, yet a comprehensive, well‐supported phylogenetic framework does not yet exist for this genus. We construct a comprehensive molecular phylogeny of Plestiodon using Bayesian phylogenetic analyses of a nine‐locus data set comprising 8308 base pairs of DNA, sampled from 38 of the 43 species in the genus. We evaluate potential gene tree/species tree discordance by conducting phylogenetic analyses of the concatenated and individual locus data sets, as well as employing coalescent‐based methods. Specifically, we address the placement of Plestiodon within the evolutionary tree of Scincidae, as well as the phylogenetic relationships between Plestiodon species, and their taxonomy. Given our sampling of major Scincidae lineages, we also re‐evaluate ‘deep’ relationships within the family, with the goal of resolving relationships that have been ambiguous in recent molecular phylogenetic analyses. We infer strong support for several scincid relationships, including a major clade of ‘scincines’ and the inter‐relationships of major Mediterranean and southern African genera. Although we could not estimate the precise phylogenetic affinities of Plestiodon with statistically significant support, we nonetheless infer significant support for its inclusion in a large ‘scincine’ clade exclusive of Acontinae, Lygosominae, Brachymeles, and Ophiomorus. Plestiodon comprises three major geographically cohesive clades. One of these clades is composed of mostly large‐bodied species inhabiting northern Indochina, south‐eastern China (including Taiwan), and the southern Ryukyu Islands of Japan. The second clade comprises species inhabiting central China (including Taiwan) and the entire Japanese archipelago. The third clade exclusively inhabits North and Middle America and the island of Bermuda. A vast majority of interspecific relationships are strongly supported in the concatenated data analysis, but there is nonetheless significant conflict amongst the individual gene trees. Coalescent‐based gene tree/species tree analyses indicate that incongruence amongst the nuclear loci may severely obscure the phylogenetic inter‐relationships of the primarily small‐bodied Plestiodon species that inhabit the central Mexican highlands. These same analyses do support the sister relationship between Plestiodon marginatus Hallowell, 1861 and Plestiodon stimpsonii (Thompson, 1912), and differ with the mitochondrial DNA analysis that supports Plestiodon elegans (Boulenger, 1887) + P. stimpsonii. Finally, because the existing Plestiodon taxonomy is a poor representation of evolutionary relationships, we replace the existing supraspecific taxonomy with one congruent with our phylogenetic results. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 163–189.  相似文献   

10.
Despite several recent studies, the phylogeny of plethodontid salamanders is not yet fully resolved and the phylogenetic positions of several key genera, especially Aneides, Hemidactylium, Hydromantes and Karsenia, are contentious. Here we present a combined dataset of complete mitochondrial genomes and three nuclear loci for 20 species (16 genera) of plethodontids, representing all major clades in the family. The combined dataset without mitochondrial third codon positions provides a fully resolved, statistically well-supported tree. In this topology two major clades are recovered. A northern clade includes Aneides, Desmognathus, Ensatina, Hydromantes, Karsenia, Phaeognathus and Plethodon, with Plethodon being the sister taxon to the rest of the clade. Hydromantes and Karsenia are sister taxa, and Aneides is recovered as the sister taxon to Ensatina. Desmognathus+Phaeognathus form the sister taxon to Aneides+Ensatina. An eastern/southern clade comprises two subclades. One subclade, the spelerpines (Eurycea, Gyrinophilus, Pseudotriton, Stereochilus, Urspelerpes) is the sister taxon to a subclade comprising Hemidactylium, Batrachoseps and the tropical plethodontids (represented by Bolitoglossa, Nototriton and Thorius). In this topology Hemidactylium is well-supported as the sister taxon to Batrachoseps. Only when mitochondrial third codon positions are included using maximum likelihood analysis is Hemidactylium recovered as the sister taxon to Batrachoseps+tropical genera. Hypothesis testing of alternative topologies supports these conclusions. On the basis of these results we propose a conservative taxonomy for Plethodontidae.  相似文献   

11.
Halichondrida is a pivotal demosponge order of which the classification underwent major changes in the recent history. The monophyly of this order and its intra-ordinal phylogeny cannot be reliably determined on the basis of morphology. Here we present a 28Sr RNA gene tree of selected halichondrids, which supports the hypothesis of halichondrid non-monophyly and elucidates further inter-ordinal relationships. We enlarged the analysis by previously published sequences, discuss how previous analyses suffer from taxon bias and analyse the resulting phylogenetic implications. Most halichondrid families (in particular Axinellidae und Dictyonellidae) cluster polyphyletic and the molecular classification of several genera does not agree with the current (morphological) system.  相似文献   

12.
Betulaceae is a well‐defined family of Fagales, including six living genera and more than 160 modern species. Species of the family have high ecological and economic value for the abundant production of wood. However, phylogenetic relationships within Betulaceae have remained partly unresolved, likely due to the lack of a sufficient number of informative sites used in previous studies. Here, we re‐investigate the Betulaceae phylogeny with whole chloroplast genomes from 24 species (17 newly assembled), representing all genera of the family. All the 24 plastomes are relatively conserved with four regions, and each genome is ∼158–161 kb long, with 111 genes. The six genera are all monophyletic in the plastome tree, whereas Ostrya Scop. is nested in the Carpinus clade in the internal transcribed spacer tree. Further incongruencies are also detected within some genera between species. Incomplete lineage sorting and/or hybrid introgression during the diversification of the family could account for such incongruencies. Our dating analysis, based on four fossils, suggests that the most recent common ancestors of the extant genera date back to the mid‐ to late Miocene, and confirms that Betulaceae started to diversify in the upper Cretaceous/early Paleocene. Our results highlight the significance of using more informative sites in resolving phylogenetic relationships. Plastome data and increased taxon sampling will help to better understand the evolutionary history of Betulaceae in the future.  相似文献   

13.
Abstract.  In this study, we assessed the ability of mitochondrial genome sequences to recover a test phylogeny of five hymenopteran taxa from which phylogenetic relationships are well accepted. Our analyses indicated that the test phylogeny was well recovered in all nucleotide Bayesian analyses when all the available holometabolan (i.e. outgroup) taxa were included, but only in Bayesian analyses excluding third codon positions when only the hymenopteran representatives and a single outgroup were included. This result suggests that taxon sampling of the outgroup might be as important as taxon sampling of the ingroup when recovering hymenopteran phylogenetic relationships using whole mitochondrial genomes. Parsimony analyses were more sensitive to both taxon sampling and the analytical model than Bayesian analyses, and analyses using the protein dataset did not recover the test phylogeny. In general, mitochondrial genomes did not resolve the position of the Hymenoptera within the Holometabola with confidence, suggesting that an increased taxon sampling, both within the Holometabola and among outgroups, is necessary.  相似文献   

14.
Ecological studies are increasingly considering phylogenetic relationships among species. The phylogeny is used as a proxy or filter to improve statistical tests and retain evolutionary elements, such as niche conservation. We used the phylogenetic topology to improve the model for occurrence of Trichoptera genera in Cerrado (Brazilian Savanna) streams. We tested whether parameters generated by logistic models of occurrence, using phylogenetic signals, are better than models generated without phylogenetic information. We used a model with Bayesian updating to examine the influence of stream water pH and phylogenetic relationship among genera on the occurrence of Trichoptera genera. Then, we compared this model with the logistic model for each Trichoptera genus. The probability of occurrence of most genera increased with water pH, and the phylogeny‐based explicit logistic model improved the parameters estimated for observed genera. The inferred relationship between genera occurrence and stream pH improved, indicating that phylogeny adds relevant information when estimating ecological responses of organisms. Water with elevated acidity (low pH values) may be restrictive for the occurrence of Trichoptera larvae, especially if the regional streams exhibit neutral to alkaline water, as is observed in the Cerrado region. Using phylogeny‐based modeling to predict species occurrence is a prominent opportunity to extend our current statistical framework based on environmental conditions, as it enables a more precise estimation of ecological parameters.  相似文献   

15.
16.
17.
The relative contribution of taxon number and gene number to accuracy in phylogenetic inference is a major issue in phylogenetics and of central importance to the choice of experimental strategies for the successful reconstruction of a broad sketch of the tree of life. Maximization of the number of taxa sampled is the strategy favored by most phylogeneticists, although its necessity remains the subject of debate. Vast increases in gene number are now possible due to advances in genomics, but large numbers of genes will be available for only modest numbers of taxa, raising the question of whether such genome-scale phylogenies will be robust to the addition of taxa. To examine the relative benefit of increasing taxon number or gene number to phylogenetic accuracy, we have developed an assay that utilizes the symmetric difference tree distance as a measure of phylogenetic accuracy. We have applied this assay to a genome-scale data matrix containing 106 genes from 14 yeast species. Our results show that increasing taxon number correlates with a slight decrease in phylogenetic accuracy. In contrast, increasing gene number has a significant positive effect on phylogenetic accuracy. Analyses of an additional taxon-rich data matrix from the same yeast clade show that taxon number does not have a significant effect on phylogenetic accuracy. The positive effect of gene number and the lack of effect of taxon number on phylogenetic accuracy are also corroborated by analyses of two data matrices from mammals and angiosperm plants, respectively. We conclude that, for typical data sets, the number of genes utilized may be a more important determinant of phylogenetic accuracy than taxon number.  相似文献   

18.
The phylogenetic relationships of species are fundamental to any biological investigation, including all evolutionary studies. Accurate inferences of sister group relationships provide the researcher with an historical framework within which the attributes or geographic origin of species (or supraspecific groups) evolved. Taken out of this phylogenetic context, interpretations of evolutionary processes or origins, geographic distributions, or speciation rates and mechanisms, are subject to nothing less than a biological experiment without controls. Cypriniformes is the most diverse clade of freshwater fishes with estimates of diversity of nearly 3,500 species. These fishes display an amazing array of morphological, ecological, behavioral, and geographic diversity and offer a tremendous opportunity to enhance our understanding of the biotic and abiotic factors associated with diversification and adaptation to environments. Given the nearly global distribution of these fishes, they serve as an important model group for a plethora of biological investigations, including indicator species for future climatic changes. The occurrence of the zebrafish, Danio rerio, in this order makes this clade a critical component in understanding and predicting the relationship between mutagenesis and phenotypic expressions in vertebrates, including humans. With the tremendous diversity in Cypriniformes, our understanding of their phylogenetic relationships has not proceeded at an acceptable rate, despite a plethora of morphological and more recent molecular studies. Most studies are pre-Hennigian in origin or include relatively small numbers of taxa. Given that analyses of small numbers of taxa for molecular characters can be compromised by peculiarities of long-branch attraction and nodal-density effect, it is critical that significant progress in our understanding of the relationships of these important fishes occurs with increasing sampling of species to mitigate these potential problems. The recent Cypriniformes Tree of Life initiative is an effort to achieve this goal with morphological and molecular (mitochondrial and nuclear) data. In this early synthesis of our understanding of the phylogenetic relationships of these fishes, all types of data have contributed historically to improving our understanding, but not all analyses are complementary in taxon sampling, thus precluding direct understanding of the impact of taxon sampling on achieving accurate phylogenetic inferences. However, recent molecular studies do provide some insight and in some instances taxon sampling can be implicated as a variable that can influence sister group relationships. Other instances may also exist but without inclusion of more taxa for both mitochondrial and nuclear genes, one cannot distinguish between inferences being dictated by taxon sampling or the origins of the molecular data.  相似文献   

19.
基于细胞色素b的鸫亚科部分鸟类的系统进化   总被引:8,自引:0,他引:8  
采用分子系统学方法对鸫亚科(Turdinae)16属35种鸟类的线粒体细胞色素b基因进行系统发生分析。所测序列经对位排列后共983bp,包含变异位点399个,简约信息位点349个。以太平鸟(Bombycillagarrulus)和雪松太平鸟(Bombycillacedrorum)为外群,采用邻接法、最大简约法、最大似然法和贝叶斯法分别构建鸫亚科的系统发生树。研究结果表明:构建的系统树将所研究鸫亚科鸟类分为2个支系。第1个支系包括鸫属(Turdus)、地鸫属(Zoothera)和宽嘴鸫属(Cochoa);第2个支系包括歌鸲属(Luscinia)、鸲属(Tarsiger)、鹊鸲属(Copsychus)、薮鸲属(Cercotrichas)、红尾鸲属(Phoenicurus)、水鸲属(Rhyacornis)、燕尾属(Enivurus)、啸鸫属(Myiophoneus)、石属(Saxicola)、属(Oenanthe)、溪鸲属(Chaimarrornis)、矶鸫属(Monticola)和欧亚鸲属(Erithacus)。其中地鸫属并非单系类群;红尾鸲属为并系发生,水鸲属和溪鸲属归并到这一支系;石属与矶鸫属互为姐妹群,再与属聚合构成另一支系;然后上述两个支系构成姐妹群;歌鸲属和鸲属聚成姐妹群。对于鹊鸲属、薮鸲属、啸鸫属、欧亚鸲属、宽嘴鸫属和燕尾属,本研究结果并没有完全解决它们在大分支内与其它属间的亲缘关系  相似文献   

20.
The phylogeny of the flycatcher genus Anairetes was previously inferred using short fragments of mitochondrial DNA and parsimony and distance-based methods. The resulting topology spurred taxonomic revision and influenced understanding of Andean biogeography. More than a decade later, we revisit the phylogeny of Anairetes tit-tyrants using more mtDNA characters, seven unlinked loci (three mitochondrial genes, six nuclear loci), more closely related outgroup taxa, partitioned Bayesian analyses, and two coalescent species-tree approaches (Bayesian estimation of species trees, BEST; Bayesian evolutionary analysis by sampling trees, (*)BEAST). Of these improvements in data and analyses, the fourfold increase in mtDNA characters was both necessary and sufficient to incur a major shift in the topology and near-complete resolution. The species-tree analyses, while theoretically preferable to concatenation or single gene approaches, yielded topologies that were compatible with mtDNA but with weaker statistical resolution at nodes. The previous results that had led to taxonomic and biogeographic reappraisal were refuted, and the current results support the resurrection of the genus Uromyias as the sister clade to Anairetes. The sister relationship between these two genera corresponds to an ecological dichotomy between a depauperate humid cloud forest clade and a diverse dry-tolerant clade that has diversified along the latitudinal axis of the Andes. The species-tree results and the concatenation results each reaffirm the primacy of mtDNA to provide phylogenetic signal for avian phylogenies at the species and subspecies level. This is due in part to the abundance of informative characters in mtDNA, and in part to its lower effective population size that causes it to more faithfully track the species tree.  相似文献   

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