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1.
The living Old World monkeys, family Cercopithecidae, are the most successful group of nonhuman primates alive today. Overall, they account for over one quarter of the extant genera of primates and approximately 40% of the species. They have an extensive fossil record extending back to the early and middle Miocene of Africa.1,2 Despite this specific diversity and a long evolutionary history, it is commonly argued that the group is relatively uniform in both its skeletal3 and dental4 anatomy, suggesting that much of the current taxonomic diversity is a relatively recent phenomenon. In such a species group, it is perhaps not surprising that the taxonomy of Old World monkeys is subject to many differing classifications. Thus, in recent years, authors have recognized as few as 10 and as many as 22 different genera within the family. Although some of this greater-than-two-fold difference in the number of genera can be attributed to the “splitting” versus “lumping” philosophies of different researchers, much of it is based on major disagreements over phylogenetic relationships. Recent studies of the genetics and chromosomes of this group have illuminated Old World monkey phylogeny in many ways. Some of these studies have resolved longstanding debates based on morphological data; others have revealed phylogenetic relationships that morphologists had never suspected.  相似文献   

2.
Z Yi  LA Katz  W Song 《PloS one》2012,7(7):e40635
The current understanding of ciliate phylogeny is mainly based on analyses of a single gene, the small subunit ribosomal RNA (SSU-rDNA). However, phylogenetic trees based on single gene sequence are not reliable estimators of species trees, and SSU-rDNA genealogies are not useful for resolution of some branches within Ciliophora. Since congruence between multiple loci is the best tool to determine evolutionary history, we assessed the usefulness of alpha-tubulin gene, a protein-coding gene that is frequently sequenced, for ciliate phylogeny. Here, we generate alpha-tubulin gene sequences of 12 genera and 30 species within the order Euplotida, one of the most frequently encountered ciliate clades with numerous apparently cosmopolitan species, as well as four genera within its putative sister order Discocephalida. Analyses of the resulting data reveal that: 1) the alpha-tubulin gene is suitable phylogenetic marker for euplotids at the family level, since both nucleotide and amino acid phylogenies recover all monophyletic euplotid families as defined by both morphological criteria and SSU-rDNA trees; however, alpha-tubulin gene is not a good marker for defining species, order and subclass; 2) for seven out of nine euplotid species for which paralogs are detected, gene duplication appears recent as paralogs are monophyletic; 3) the order Euplotida is non-monophyletic, and the family Uronychiidae with sequences from four genera, is non-monophyletic; and 4) there is more genetic diversity within the family Euplotidae than is evident from dargyrome (geometrical pattern of dorsal "silverline system" in ciliates) patterns, habit and SSU-rDNA phylogeny, which indicates the urgent need for taxonomic revision in this area.  相似文献   

3.
The babblers (Timaliidae) form a large songbird family, which achieves its highest diversity in South-East Asia. As part of an ongoing phylogenetic investigation of this group, we focus here on the systematic position of two Asian genera, Yuhina and Stachyris , using cytochrome b , 16S and 12S sequence data. The analysis suggests that the two genera, as defined by morphological characters, are not monophyletic. The white-bellied yuhina Yuhina zantholeuca , which has been placed among the typical yuhinas by most authors, is not a babbler. The other yuhinas studied, six continental species and a species endemic to Taiwan, form a clade that includes also three species of Stachyris endemic to the Philippines. The other Stachyris are not related to this clade, and can be divided into two groups that correspond to morphological and geographical differences among the species.  相似文献   

4.

Background  

Adaptive radiation, the evolution of ecological and phenotypic diversity from a common ancestor, is a central concept in evolutionary biology and characterizes the evolutionary histories of many groups of organisms. One such group is the Mustelidae, the most species-rich family within the mammalian order Carnivora, encompassing 59 species classified into 22 genera. Extant mustelids display extensive ecomorphological diversity, with different lineages having evolved into an array of adaptive zones, from fossorial badgers to semi-aquatic otters. Mustelids are also widely distributed, with multiple genera found on different continents. As with other groups that have undergone adaptive radiation, resolving the phylogenetic history of mustelids presents a number of challenges because ecomorphological convergence may potentially confound morphologically based phylogenetic inferences, and because adaptive radiations often include one or more periods of rapid cladogenesis that require a large amount of data to resolve.  相似文献   

5.
Elevational variation in species richness is ubiquitous and important for conservation, but remains poorly explained. Numerous studies have documented higher species richness at mid-elevations, but none have addressed the underlying evolutionary and biogeographic processes that ultimately explain this pattern (i.e. speciation, extinction and dispersal). Here, we address the evolutionary causes of the mid-elevational diversity hump in the most species-rich clade of salamanders, the tropical bolitoglossine plethodontids. We present a new phylogeny for the group based on DNA sequences from all 13 genera and 137 species. Using this phylogeny, we find no relationship between rates of diversification of clades and their elevational distribution, and no evidence for a rapid 'species pump' in tropical montane regions. Instead, we find a strong relationship between the number of species in each elevational zone and the estimated time when each elevational band was first colonized. Mid-elevation habitats were colonized early in the phylogenetic history of bolitoglossines, and given similar rates of diversification across elevations, more species have accumulated in the elevational zones that were inhabited the longest. This pattern may be widespread and suggests that mid-elevation habitats may not only harbour more species, but may also contain more phylogenetic diversity than other habitats within a region.  相似文献   

6.
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   

7.
Order Diplobathrida is a major clade of camerate crinoids spanning the Ordovician–Mississippian, yet phylogenetic relationships have only been inferred for Ordovician taxa. This has hampered efforts to construct a comprehensive tree of life for crinoids and develop a classification scheme that adequately reflects diplobathrid evolutionary history. Here, I apply maximum parsimony and Bayesian phylogenetic approaches to the fossil record of diplobathrids to infer the largest tree of fossil crinoids to date, with over 100 genera included. Recovered trees provide a framework for evaluating the current classification of diplobathrids. Notably, previous suborder divisions are not supported, and superfamily divisions will require significant modification. Although numerous revisions are required for families, most can be retained through reassignment of genera. In addition, recovered trees were used to produce phylogeny‐based estimates of diplobathrid lineage diversity. By accounting for ghost lineages, phylogeny‐based richness estimates offer greater insight into diversification and extinction dynamics than traditional taxonomy‐based approaches alone and provide a detailed summary of the ~150 million‐year evolutionary history of Diplobathrida. This study constitutes a major step toward producing a phylogeny of the Crinoidea and documenting crinoid diversity dynamics. In addition, it will serve as a framework for subsequent phylogeny‐based investigations of macroevolutionary questions.  相似文献   

8.
Chinese Araliaceae consist of 20 genera and ca. 175 species. To assess the evolutionary relationships of Araliaceae and their biogeographic diversification in China, the phylogeny of Chinese Araliaceae was constructed by sampling 96 accessions representing 20 genera and 50 species of Chinese Araliaceae and 45 closely related taxa using sequences of the nuclear ribosomal internal transcribed spacer (ITS) region and six plastid regions (the ndhF gene, the trnL-trnF region, the rps16intron, the atpB-rbcL intergenic spacer, the rpl16 intron, and the psbA-trnH intergenic spacer). Phylogenetic analyses of the combined plastid and ITS data supported the results of the previously studies that the Chinese members of Araliaceae were scattered within the Asian Palmate group and the Aralia-Panax group withOsmoxylon at the base of core Araliaceae. The generic status of Pentapanax and Tupidanthus is not supported. Our analysis clearly places them in Aralia and AsianSchefflera, respectively. In a broader phylogenetic framework of Araliaceae, based on the fossil-calibrated Bayesian dating, Chinese Araliaceae was inferred to have originated in Asia and underwent a rapid radiation in its evolutionary history. Its diversification is hypothesized to have been driven largely by the orogenies in Asia during the Cenozoic. In China, the distribution pattern of the phylogenetic diversity of Araliaceae corresponds with its taxonomic diversity across the entire region.  相似文献   

9.
Although tortoises of the family Testudinidae represent a familiar and widely distributed group of turtles, their phylogenetic relationships have remained contentious. In this study, we included 32 testudinid species (all genera and subgenera, and all species of Geochelone, representing 65% of the total familial species diversity), and both mitochondrial (12S rRNA, 16S rRNA, and cytb) and nuclear (Cmos and Rag2) DNA data with a total of 3387 aligned characters. Using diverse phylogenetic methods (Maximum Parsimony, Maximum Likelihood, and Bayesian Analysis) congruent support is found for a well-resolved phylogeny. The most basal testudinid lineage includes a novel sister relationship between Asian Manouria and North American Gopherus. In addition, this phylogeny supports two other major testudinid clades: Indotestudo+Malacochersus+Testudo; and a diverse clade including Pyxis, Aldabrachelys, Homopus, Chersina, Psammobates, Kinixys, and Geochelone. However, we find Geochelone rampantly polyphyletic, with species distributed in at least four independent clades. Biogeographic analysis based on this phylogeny is consistent with an Asian origin for the family (as supported by the fossil record), but rejects the long-standing hypothesis of South American tortoises originating in North America. By contrast, and of special significance, our results support Africa as the ancestral continental area for all testudinids except Manouria and Gopherus. Based on our systematic findings, we also propose modifications concerning Testudinidae taxonomy.  相似文献   

10.
Most plant phylogenetic inference has used DNA sequence data from the plastid genome. This genome represents a single genealogical sample with no recombination among genes, potentially limiting the resolution of evolutionary relationships in some contexts. In contrast, nuclear DNA is inherently more difficult to employ for phylogeny reconstruction because major mutational events in the genome, including polyploidization, gene duplication, and gene extinction can result in homologous gene copies that are difficult to identify as orthologs or paralogs. Gene tree parsimony (GTP) can be used to infer the rooted species tree by fitting gene genealogies to species trees while simultaneously minimizing the estimated number of duplications needed to reconcile conflicts among them. Here, we use GTP for five nuclear gene families and a previously published plastid data set to reconstruct the phylogenetic backbone of the aquatic plant family Pontederiaceae. Plastid-based phylogenetic studies strongly supported extensive paraphyly of Eichhornia (one of the four major genera) but also depicted considerable ambiguity concerning the true root placement for the family. Our results indicate that species trees inferred from the nuclear genes (alone and in combination with the plastid data) are highly congruent with gene trees inferred from plastid data alone. Consideration of optimal and suboptimal gene tree reconciliations place the root of the family at (or near) a branch leading to the rare and locally restricted E. meyeri. We also explore methods to incorporate uncertainty in individual gene trees during reconciliation by considering their individual bootstrap profiles and relate inferred excesses of gene duplication events on individual branches to whole-genome duplication events inferred for the same branches. Our study improves understanding of the phylogenetic history of Pontederiaceae and also demonstrates the utility of GTP for phylogenetic analysis.  相似文献   

11.
ABSTRACT: BACKGROUND: The fish family Haemulidae is divided in two subfamilies, Haemulinae and Plectorhynchinae (sweetlips), including approximately 17 genera and 145 species. The family has a broad geographic distribution that encompasses contrasting ecological habitats resulting in a unique potential for evolutionary hypotheses testing. In the present work we have examined the phylogenetic relationships of the family using selected representatives of additional Percomorpha based on Bayesian and Maximum likelihood methods by means of three mitochondrial genes. We also developed a phylogenetic hypothesis of the New World species based on five molecular markers (three mitochondrial and two nuclear) as a framework to evaluate the evolutionary history, the ecological diversification and speciation patterns of this group. RESULTS: Mitochondrial genes and different reconstruction methods consistently recovered a monophyletic Haemulidae with the Sillaginidae as its sister clade (although with low support values). Previous studies proposed different relationships that were not recovered in this analysis. We also present a robust molecular phylogeny of Haemulinae based on the combined data of two nuclear and three mitochondrial genes. All topologies support the monophyly of both sub-families (Haemulinae, Plectorhinchinae). The genus Pomadasys was shown to be polyphyletic and Haemulon, Anisotremus, and Plectorhinchus were found to be paraphyletic. Four of seven presumed geminate pairs were indeed found to be sister species, however our data did not support a contemporaneous divergence. Analyses also revealed that differential use of habitat might have played an important role in the speciation dynamics of this group of fishes, in particular among New World species where extensive sample coverage was available. CONCLUSIONS: This study provides a new hypothesis for the sister clade of Hamulidae and a robust phylogeny of the latter. The presence of para- and polyphyletic genera underscores the need for a taxonomic reassessment within the family. A scarce sampling of the Old World Pomadasys species prevents us to definitively point to a New World origin of the sub-familiy Haemulinae, however our data suggest that this is likely to be the case. This study also illustrates how life history habitat influences speciation and evolutionary trajectories.  相似文献   

12.
Canonical microsporidians are a group of obligate intracellular parasites of a wide range of hosts comprising ~1,300 species of >220 genera. Microsporidians are related to fungi, and many characterised and uncharacterized groups closely related to them have been discovered recently, filling the knowledge gaps between them. These groups assigned to the superphylum Opisthosporidia have provided several important insights into the evolution of diverse intracellular parasitic lineages within the tree of eukaryotes. The most studied among opisthosporidians, canonical microsporidians, were known to science more than 160 years ago, however, the classification of canonical Microsporidia has been challenging due to common morphological homoplasy, and accelerated evolutionary rates. Instead of morphological characters, ssrRNA sequences have been used as the primary data for the classification of canonical microsporidians. Previous studies have produced a useful backbone of the microsporidian phylogeny, but provided only some nodal support, causing some confusion. Here, we reconstructed phylogenetic trees of canonical microsporidians using Bayesian and Maximum Likelihood inferences. We included rRNA sequences of 126 described/named genera, by far the broadest taxon coverage to date. Overall, our trees show similar topology and recovered four of the five main clades demonstrated in previous studies (Clades 1, 3, 4 and 5). Family level clades were well resolved within each major clade, but many were discordant with the recently revised classification. Therefore, revision and some reshuffling, especially within and between Clades 1 and 3 are required. We also reconstructed phylogenetic trees of Opisthosporidia to better integrate the evolutionary history of canonical microsporidians in a broader context. We discuss several traits shared only by canonical microsporidians that may have contributed to their striking ecological success in diverse metazoans. More targeted studies on the neglected host groups will be of value for a better understanding of the evolutionary history of these interesting intracellular parasites.  相似文献   

13.
Phylogenies are essential to studies investigating the effect of evolutionary history on assembly of species in ecological communities and geographical and ecological patterns of phylogenetic structure of species assemblages. Because phylogenies well resolved at the species level are lacking for many major groups of organisms such as vascular plants, researchers often generate a species-level phylogenies using a phylogeny well resolved at the genus level as a backbone and attaching species to their respective genera in the phylogeny as polytomies or by using a megaphylogeny well resolved at the genus level as a backbone and adding additional species to the megaphylogeny as polytomies of their respective genera. However, whether the result of a study using species-level phylogenies generated in these ways is robust, compared to that based on phylogenies fully resolved at the species level, has not been assessed. Here, we use 1093 angiosperm tree assemblages (each in a 110 × 110 km quadrat) in North America as a model system to address this question, by examining six commonly used metrics of phylogenetic structure (phylogenetic diversity and phylogenetic relatedness) and six climate variables commonly used in ecology. Our results showed that (1) the scores of phylogenetic metrics derived from species-level phylogenies resolved at the genus level with species being attached to their respective genera as polytomies are very strongly or perfectly correlated to those derived from a phylogeny fully resolved at the species level (the mean of correlation coefficients is 0.973), and (2) the relationships between the scores of phylogenetic metrics and climate variables are consistent between the two sets of analyses based on the two types of phylogeny. Our study suggests that using species-level phylogenies resolved at the genus level with species being attached to their genera as polytomies is appropriate in studies exploring patterns of phylogenetic structure of species in ecological communities across geographical and ecological gradients.  相似文献   

14.
The publication of the world catalog of terrestrial isopods some ten years ago by Schmalfuss has facilitated research on isopod diversity patterns at a global scale. Furthermore, even though we still lack a comprehensive and robust phylogeny of Oniscidea, we do have some useful approaches to phylogenetic relationships among major clades which can offer additional insights into isopod evolutionary dynamics. Taxonomic diversity is one of many approaches to biodiversity and, despite its sensitiveness to biases in taxonomic practice, has proved useful in exploring diversification dynamics of various taxa. In the present work, we attempt an analysis of taxonomic diversity patterns among Oniscidea based on an updated world list of species containing 3,710 species belonging to 527 genera and 37 families (data till April 2014). The analysis explores species diversity at the genus and family level, as well as the relationships between species per genera, species per families, and genera per families. In addition, we consider the structure of isopod taxonomic system under the fractal perspective that has been proposed as a measure of a taxon’s diversification. Finally, we check whether there is any phylogenetic signal behind taxonomic diversity patterns. The results can be useful in a more detailed elaboration of Oniscidea systematics.  相似文献   

15.
The phylogenetic relationships of the Timaliidae (babblers) and Sylviidae (warblers) have long challenged ornithologists. We focus here on three Malagasy genera currently assigned to the Timaliidae, Mystacornis, Oxylabes, and Neomixis, and on their relationships with other babblers and warblers using the sequences of two mitochondrial genes (cytochrome b and 16S rRNA). Maximum parsimony analyses show that the Malagasy "babblers" are not related to any of the other African and Asian babblers. The genus Mystacornis is neither a babbler nor a warbler. The other Malagasy "babblers" are members of warbler groups (the monophyly of the Sylviidae is not demonstrated). Oxylabes madagascariensis and Hartertula flavoviridis (we recognize Hartertula as a genus for the species flavoviridis, previously Neomixis flavoviridis) constitute, with two presumed sylviine taxa, Thamnornis chloropetoides and Cryptosylvicola randrianasoloi, a warbler radiation endemic to the island of Madagascar. The other Neomixis species (tenella, striatigula, and viridis) belong to another warbler group comprising cisticoline taxa. These results show that the Timaliidae did not disperse to Madagascar. Rather, the island has been colonized, independently, by at least two clades of warblers, probably originating from Africa, where the Sylviidae radiation has been the most extensive.  相似文献   

16.
Grasses are widespread on every continent and are found in all terrestrial biomes. The dominance and spread of grasses and grassland ecosystems have led to significant changes in Earth′s climate, geochemistry, and biodiversity. The abundance of DNA sequence data, particularly chloroplast sequences, and advances in placing grass fossils within the family allows for a reappraisal of the family′s origins, timing, and geographic spread and the factors that have promoted diversification. We reconstructed a time-calibrated grass phylogeny and inferred ancestral areas using chloroplast DNA sequences from nearly 90% of extant grass genera. With a few notable exceptions, the phylogeny is well resolved to the subtribal level. The family began to diversify in the Early–Late Cretaceous (crown age of 98.54 Ma) on West Gondwana before the complete split between Africa and South America. Vicariance from the splitting of Gondwana may be responsible for the initial divergence in the family. However, Africa clearly served as the center of origin for much of the early diversification of the family. With this phylogenetic, temporal, and spatial framework, we review the evolution and biogeography of the family with the aim to facilitate the testing of biogeographical hypotheses about its origins, evolutionary tempo, and diversification. The current classification of the family is discussed with an extensive review of the extant diversity and distribution of species, molecular and morphological evidence supporting the current classification scheme, and the evidence informing our understanding of the biogeographical history of the family.  相似文献   

17.
Tao W  Zou M  Wang X  Gan X  Mayden RL  He S 《PloS one》2010,5(10):e13508
Despite their great diversity and biological importance, evolutionary relationships among the endemic clade of East Asian Cyprinidae remain ambiguous. Understanding the phylogenetic history of this group involves many challenges. For instance, ecomorphological convergence may confound morphology-based phylogenetic inferences, and previous molecular phylogenetic studies based on single genes have often yielded contradictory and poorly supported trees. We assembled a comprehensive data matrix of 100 nuclear gene segments (~ 71132 base pairs) for representative species of the endemic East Asian cyprinid fauna and recovered a robust phylogeny from this genome-wide signal supported by multiple analytical methods, including maximum parsimony, maximum likelihood and Bayesian inference. Relaxed molecular clock analyses indicated species radiations of this clade concentrated at approximately 1.9-7.6 MYA. We provide evidence that the bursts of diversification in this fauna are directly linked to major paleoenvironmental events associated with monsoon evolution occurring from late Miocene to Pliocene. Ancestral state reconstruction reveals convergent morphological characters are hypothesized to be independent products of similar selective pressures in ecosystems. Our study is the first comprehensive phylogenetic study of the enigmatic East-Asian cyprinids. The explicit molecular phylogeny provides a valuable framework for future research in genome evolution, adaptation and speciation of cyprinids.  相似文献   

18.
19.
The bulbuls comprise an ecologically important group of frugivorous, seed‐dispersing birds found in Asia and Africa. Although several studies have examined the phylogenetic relationships of subsets of bulbul species, a comprehensive phylogeny of the family Pycnonotidae has hitherto been lacking. We used publicly available sequences generated from previous phylogenetic studies, augmented by new sequences from several unstudied taxa, to create a supermatrix from which to infer the phylogeny of the family. In all, we compared 121 of the 130 bulbul species. Our tree supports the monophyly of the family and comprises an exclusively African and a predominantly Asian clade. Several genera were found not to be monophyletic and we suggest taxonomic changes to provide a more accurate classification based on phylogeny.  相似文献   

20.

Background  

The teleost order Lophiiformes, commonly known as the anglerfishes, contains a diverse array of marine fishes, ranging from benthic shallow-water dwellers to highly modified deep-sea midwater species. They comprise 321 living species placed in 68 genera, 18 families and 5 suborders, but approximately half of the species diversity is occupied by deep-sea ceratioids distributed among 11 families. The evolutionary origins of such remarkable habitat and species diversity, however, remain elusive because of the lack of fresh material for a majority of the deep-sea ceratioids and incompleteness of the fossil record across all of the Lophiiformes. To obtain a comprehensive picture of the phylogeny and evolutionary history of the anglerfishes, we assembled whole mitochondrial genome (mitogenome) sequences from 39 lophiiforms (33 newly determined during this study) representing all five suborders and 17 of the 18 families. Sequences of 77 higher teleosts including the 39 lophiiform sequences were unambiguously aligned and subjected to phylogenetic analysis and divergence time estimation.  相似文献   

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