首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 9 毫秒
1.
Territorial song structures are often the most prominent characters for distinguishing closely related taxa among songbirds. Learning processes may cause convergent evolution of passerine songs, but phylogenetic information of acoustic traits can be investigated with the help of molecular phylogenies, which are not affected by cultural evolutionary processes. We used a phylogeny based on cytochrome b sequences to trace the evolution of territorial song within the genus Regulus. Five discrete song units are defined as basic components of regulid song via sonagraphic measurements. Traits of each unit are traced on a molecular tree and a mean acoustic character difference between taxon pairs is calculated. Acoustic divergence between regulid taxa correlates strongly with genetic distances. Syntax features of complete songs and of single units are most consistent with the molecular data, whereas the abundance of certain element types is not. Whether song characters are innate or learned was interpreted using hand-reared birds in aviary experiments. We found that convergent character evolution seems to be most probable for learned acoustic traits. We conclude that syntax traits of whole verses or subunits of territorial song, especially innate song structures, are the most reliable acoustic traits for phylogenetic reconstructions in Regulus.  相似文献   

2.
通过构建分子钟对广义柏科主要分类群的起源时间进行探讨。采用相对速率检验法分析广义柏科mat K、rbc L进化速率的稳定性,结果显示rbc L的非同义替代速率只在Pinaceae与Taxodiaceae的分类群及柏科北半球的支系(Cupressoideae)之间通过相对速率检验,而Pinaceae与柏科南半球分支(Callitrodeae)之间没有通过相对速率检验。mar K基因的非同义替代速率在Pinaceae与广义柏科的所有分类群之间通过相对速率检验。根据通过相对速率检验的分类群之间的遗传距离和基因进化速率,计算它们发生分歧的时间。据此推测,杉科的主要分类群Taiwanioideae、Athrotaxidoideae、Sequoioideae与其他分支发生分歧的时间均在侏罗纪,支持现存杉科在侏罗纪就已经建立起来的观点;Cupressaceae(s.s.)的两个支系(亚科)发生分歧的时间在124Ma之前,相当于早白垩世早期,可能由于南北古大陆的完全分离,其祖先居群被分隔成两个亚群,随后各自演化为不同的支系。Callitirodeae、Cupressoideae各属发生分歧的时间也均在白垩纪,表明Cupressaceae(s.s.)在白垩纪就已经建立起来。  相似文献   

3.
This study investigates the molecular phylogeny of seven lionfishes of the genera Dendrochirus and Pterois. MP, ML, and NJ phylogenetic analysis based on 964 bp of partial mitochondrial DNA sequences (cytochrome b and 16S rDNA) revealed two main clades: (1) “Pterois” clade (Pterois miles and Pterois volitans), and (2) “Pteropterus–Dendrochirus” clade (remainder of the sampled species). The position of Dendrochirus brachypterus either basal to the main clades or in the “Pteropterus–Dendrochirus” clade cannot be resolved. However, the molecular phylogeny did not support the current separation of the genera Pterois and Dendrochirus. The siblings P. miles and P. volitans are clearly separated and our results support the proposed allopatric or parapatric distribution in the Indian and Pacific Ocean. However, the present analysis cannot reveal if P. miles and P. volitans are separate species or two populations of a single species, because the observed separation in different clades can be either explained by speciation or lineage sorting. Molecular clock estimates for the siblings P. miles and P. volitans suggest a divergence time of 2.4–8.3 mya, which coincide with geological events that created vicariance between populations of the Indian and Pacific Ocean.  相似文献   

4.
? Premise of the Study: Little research has been done at the molecular level on the tribe Fumarieae (Papaveraceae). Papaveraceae is a model plant group for studying evolutionary patterns despite the lack of a reference phylogeny for this tribe. We investigated the phylogenetic relationships within the tribe to complete the molecular data for this family in order to help understand its character evolution and biogeographic pattern. ? Methods: We used maximum-parsimony and Bayesian approaches to analyze five DNA regions for 25 species representing 10 of the 11 Fumarieae genera and five outgroups. Evolutionary pathways of four characters (habit, life span, type of fruit, and number of seeds per fruit) were inferred on the phylogeny using parsimony. The ancestral distribution areas were reconstructed using dispersal-vicariance analysis. ? Key Results: Fumarieae is monophyletic and includes three groups that agree with the morphology-based subtribes: Discocapninae, Fumariinae, and Sarcocapninae. Within subtribes, the relationships among genera were different from those obtained with morphological data. Annual life span, nonchasmophytic habit, and a several-seeded capsule were the basal character states for the tribe. The ancestor occupied a continuous area between West Eurasia and Africa. Vicariances explain the divergence between lineages Discocapninae (South Africa) and Fumariinae-Sarcocapninae (Mediterranean), and the disjunction of Fumariinae (Mediterranean-Central Asia). ? Conclusions: Molecular phylogeny confirms the subtribal classification of Fumarieae based on morphology. However it provides different results regarding the relationships among genera within each subtribe, which affects the inference of the evolutionary pathway followed by the four selected characters. The disjunct distribution of the tribe is explained by different vicariance scenarios.  相似文献   

5.
With about 60,000 described species, Curculionoidea represent the most species-rich superfamily in the animal kingdom. The immense diversity apparently creates difficulties in the reconstruction of the phylogenetic relationships. Independent morphological studies have led to very different classifications. This study is based on molecular data from two independent molecular sources, the 16S and 18S rDNA. Sensitivity analyses were conducted for the sequence alignment (gap costs were varied) as well as the phylogenetic reconstruction algorithms and some of their parameters. The higher-level relationships reconstructed within Curculionoidea are sensitive to alignment and reconstruction method. Nemonychidae or Oxycorynidae+Belidae were found to be sister to all remaining Curculionoidea in many analyses. The 16S rDNA sequence data (obtained from 157 species) corroborate many tribes and genera as monophyletic. It is observed that the phylogenetic reconstruction of genera with specific genetic features such as polyploidy and parthenogenetic reproduction is difficult in weevils. The curculionid subfamily Lixinae appears monophyletic. A new monophylum consisting of Entiminae, Hyperinae, Cyclominae, Myllorhinus plus possibly the Cossoninae is distinguished and we call it Entiminae s.l. For most other subfamilies and families homoplasy concealed the phylogenetic signal (due to saturation of the 16S sequences), or the species sampling was insufficient, although our sampling scheme was rather broad. We observed that although data from one source can easily be misleading (16S) or hardly informative (18S), the combination of the two independent data sets can result in useful information for such a speciose group of organisms. Our study represents the most thorough analysis of molecular sequence data of the Curculionoidea to date and although the phylogenetic results appear less stable than expected, they reflect the information content of these sequence data realistically and thus contribute to the total knowledge about the phylogeny of the Curculionoidea.  相似文献   

6.
Partial sequences of nuLSU rDNA were obtained to investigate the phylogenetic relationships of Pyronemataceae, the largest and least studied family of Pezizales. The dataset includes sequences for 162 species from 51 genera of Pyronemataceae, and 39 species from an additional 13 families of Pezizales. Parsimony, ML, and Bayesian analyses suggest that Pyronemataceae is not monophyletic as it is currently circumscribed. Ascodesmidaceae is nested within Pyronemataceae, and several pyronemataceous taxa are resolved outside the family. Glaziellaceae forms the sister group to Pyronemataceae in ML analyses, but this relationship, as well as those of Pyronemataceae to the other members of the lineage, are not resolved with support. Fourteen clades of pyronemataceous taxa are well supported and/or present in all recovered trees. Several pyronemataceous genera are suggested to be non-monophyletic, including Anthracobia, Cheilymenia, Geopyxis, Humaria, Lasiobolidium, Neottiella, Octospora, Pulvinula, Stephensia, Tricharina, and Trichophaea. Cleistothecial and truffle or truffle-like ascomata forms appear to have evolved independently multiple times within Pyronemataceae. Results of these analyses do not support previous classifications of Pyronemataceae, and suggest that morphological characters traditionally used to segregate the family into subfamilial groups are not phylogenetically informative above the genus level.  相似文献   

7.
Mitochondrial DNA sequences of approximately 1.5 kbp including the NADH dehydrogenase subunit 2 (ND2) gene and its flanking gene regions were determined for 20 species from the freshwater fish family Channidae and 3 species from Nandidae, Badidae, and Osphronemidae. Channa orientalis and C. gachua had an approximately 170-bp insertion between the tRNAMet and ND2 genes, where a 5′-half of the insertion was similar to the 5′-end portion of the ND2 gene and a 3′-half was homologous to the tRNAMet gene. This insertion may thus have originated from a tandem gene duplication that occurred in a common ancestor of these two sister species. Molecular phylogenetic analyses from different tree-building methods consistently suggested the mutual monophyly of the African and Asian taxa and the existence of several clades within the Asian taxa, some of which correspond to distinct morphological features. Our molecular phylogeny clearly supported multiple independent losses of pelvic fins on Asian lineages in parallel. Divergence time estimation based on some reasonable assumptions without assuming the molecular clock suggested the early Cretaceous divergence of the African and Asian channids. The results thus support an ancient vicariant divergence of the African and Asian channids, rather than the more recent dispersal between African and Eurasian continents.  相似文献   

8.
Historically, Pappophoreae included the genera Cottea, Enneapogon, Kaokochloa, Pappophorum and Schmidtia. Some authors consider this tribe as a well-supported monophyletic group; while other evidences reveals Pappophoreae as polyphyletic, with Pappophorum separated from the rest of the tribe. When the latter happens, it can form a clade with Tridens flavus. Molecular phylogenetic analyses of the subfamily Chloridoideae have included few species of Pappophoreae; therefore, further research involving more representatives of this tribe is needed. With the aim of providing new evidence to help clarify the phylogenetic position of Pappophorum and its relationships with other genera of the tribe and the subfamily Chloridoideae, eight new sequences of ITS and trnL-F regions of Pappophoreae species were generated. These sequences were analyzed together with other available sequence data obtained from GenBank, using maximum parsimony and Bayesian inference, for individual (trnL-F or ITS) or combined trnL-F/ITS data sets. All analyses reveal that Pappophoreae is polyphyletic, with Pappophorum separated from the rest of the tribe forming a well-supported clade sister to Tridens flavus.  相似文献   

9.
Phylogenetic relationships within Malvaceae s.l., a clade that includes the traditional families Bombacaceae, Malvaceae s.str., Sterculiaceae, and Tiliaceae, have become greatly clarified thanks to recent molecular systematic research. In this paper, we use DNA sequences of four plastid regions (atpB, matK, ndhF, and rbcL) to study relationships within Malvadendrina, one of the two major clades of Malvaceae s.l. The four data sets were generally in agreement, but five terminal taxa manifested highly unexpected affinities in the rbcL partition, and the non-coding sequences of the trnK intron were found to provide limited phylogenetic information for resolving relationships at the base of Malvadendrina. The remaining data strongly support the existence of six major clades within Malvadendrina: Brownlowioideae, Dombeyoideae, Helicteroideae, Malvatheca (comprising Bombacoideae and Malvoideae), Sterculioideae, and Tilioideae. These data also resolve the placement of two problematic taxa: Nesogordonia (in Dombeyoideae) and Mortoniodendron (in Tilioideae). The relationships among the six clades are not definitively resolved, but the best-supported topology has Dombeyoideae as sister to the remainder of Malvadendrina (posterior probability PP=80%) and Sterculioideae as sister to Malvatheca (PP=86%). This early branching position of Dombeyoideae is supported by similarities in floral characters between members of that clade and outgroup taxa in Byttnerioideae. Similarly, the sister-group relationship of Sterculioideae and Malvatheca receives support from androecial characteristics, like subsessile or sessile anthers and an absence of staminodes, shared by these two clades.  相似文献   

10.
The phylogeny of representative species of Chinese ranids was reconstructed using two nuclear (tyrosinase and rhodopsin) and two mitochondrial (12S rRNA, 16S rRNA) DNA fragments. Maximum parsimony, Bayesian, and maximum likelihood analyses were employed. In comparison with the results from nuclear and mitochondrial data, we used nuclear gene data as our preferred phylogenetic hypothesis. We proposed two families (Ranidae, Dicroglossidae) for Chinese ranids, with the exception of genus Ingerana. Within Dicroglossidae, four tribes were supported including Dicroglossini, Paini, Limnonectini, and Occidozygini. A broader sampling strategy and evidence from additional molecular markers are required to decisively evaluate the evolutionary history of Chinese ranids.  相似文献   

11.
The Order Stolidobranchiata comprises the families Pyuridae, Styelidae and Molgulidae. Early molecular data was consistent with monophyly of the Stolidobranchiata and also the Molgulidae. Internal phylogeny and relationships between Styelidae and Pyuridae were inconclusive however. In order to clarify these points we used mitochondrial and nuclear sequences from 31 species of Styelidae and 25 of Pyuridae. Phylogenetic trees recovered the Pyuridae as a monophyletic clade, and their genera appeared as monophyletic with the exception of Pyura. The Styelidae, on the other hand, appeared as a paraphyletic group split into several clades. One of them was formed by solitary oviparous species, of which the Pyuridae were a sister group. A second clade included the colonial genera Botryllus, Botrylloides and Symplegma. The remaining colonial and solitary genera formed several poorly resolved clades. One of the more species genus, Polycarpa, was shown to be polyphyletic, and the species Styela plicata grouped into two genetically distant clades suggesting the existence of two cryptic species. The internal phylogeny of Styelidae has bearings on the origin of coloniality in this family. We suggest to abandon the traditional division of colonial forms into social and compound species and use instead the categories of aggregated colonies that do not have common vascular systems, and integrated colonies, that do possess such systems. Our molecular results indicate that there have been several independent acquisitions of coloniality in the Styelidae, and that viviparity may be a pre-adaptation for a colonial life-style.  相似文献   

12.
After reconsidering the specific characters of Omphalia giovanellae and applying data from the sequences of the D1–D2 domain of the 28S rRNA gene and the ITS region of material collected in Italy and Spain, the species is ascribed to the genus Clitopilus. Considering the rather peculiar characters, especially the smooth spores, C. giovanellae is ascribed to the new section Omphaloidei sect. nov. The species is illustrated with drawings of fresh basidiomata observed in situ, as well as with SEM micrographs of the spores. Also based on DNA sequence data, O. farinolens, recently described from Spain, is shown to be a synonym of C. giovanellae.  相似文献   

13.
14.
Rhipicephalus sanguineus Latreille (1806) (Ixodida: Ixodidae) is considered to be the most widely distributed tick and to have a vast range of habitats and hosts, including livestock, pets and wildlife. In addition to morphological differences, recent investigations using approaches based on molecular genetic markers have revealed the existence of different R. sanguineus lineages in different geographic regions. In this study, 475 ticks collected from dogs in the western Iberian peninsula were studied both morphologically and genetically, using 12S and 16S rDNA and COI gene markers in order to clarify the controversy over the systematic status of R. sanguineus sensu lato in Western Europe, and to compare the present data with those sourced from studies conducted in other regions of the world. Despite the high morphometric variability, particularly on spiracles in both genders and in female genitalia, data obtained with different genetic molecular markers show very low variability, suggesting the existence of a unique species. In addition, the phylogenetic analysis showed genetic uniformity, supporting the existence of a well‐defined clade consisting of R. sanguineus s.l. specimens from Western Europe that are distinct from R. sanguineus s.l. from Africa. Furthermore, these data corroborate the existence of a polymorphic species in Western Europe, which requires to be consensually redescribed in view of its medical and veterinary importance in pathogen transmission.  相似文献   

15.
广义铃兰族包括6属200余种单子叶植物,具有较为稳定的染色体数目以及明显的核型变化,是研究植物染色体进化非常理想的类群.该研究采用常规压片法对铃兰族5个物种植物的染色体形态、数目及其核型进行了观察分析,并全面收集和整理了铃兰族所有已报道的共81种253条的染色体记录,通过综合统计、重建系统发育树,探讨铃兰族属间以及各属...  相似文献   

16.
17.
The Sematophyllaceae s.l. (Sematophyllaceae s.str. + Pylaisiadelphaceae) is one of the most diversified families of pleurocarpous mosses, distributed worldwide. The familial definition and subfamilial delimitation of the family have been controversial since their inception. Phylogenetic analyses were carried out using Bayesian inference, maximum likelihood, and maximum parsimony analyses. Our molecular phylogenetic analysis using five molecular markers (nad5, rbcL, rps4, trnL-F, and 26S) from mitochondrial, chloroplast, and nuclear genomes revealed the paraphyly of the Pylaisiadelphaceae and the monophyly of Sematophyllaceae s.l. Based on the molecular and morphological evidence, the Sematophyllaceae s.l. were further divided into six subfamilies, Taxithelioideae, Isopterygoideae, Pylaisiadelphoideae, Aptychelloideae, Platygyrioideae, and Sematophylloideae. The Taxithelioideae is established to accommodate Taxithelium, Taxitheliella, and Vernieri, the Isopterygoideae is established to accommodate Isopterygium and Yakushimabryum, the Pylaisiadelphoideae is newly circumscribed to accommodate Brotherella, Pylaisiadelpha, and Orientobryum, the Aptychelloideae is established to accommodate Aptychella, the Platygyrioideae is temporarily established to accommodate Clastobryella, Clastobryum, Gammiella, Platygyrium, and Trachyphyllum, the Sematophylloideae is resurrected to accommodate the Sematophyllaceae s.str., and Isocladiella, Isocladiellopsis, Mastopoma, Heterophyllium, Pseudotrismegistia, Trismegistia, and Wijkia are transferred to the subfamily. A new classification for the Sematophyllaceae s.l. is then proposed.  相似文献   

18.
The mitochondrial DNA evolution of the western Canary Island lacertid, Galloti galloti , was studied using six restriction enzymes ( Hae III, Mva I, Hin fl, Taq I, Msp I and Dsa V). The population phytogeny ( G. stehlini , from the adjacent island of Gran Canada, was used as an outgroup) based on 56 restriction fragments from the first two enzymes indicates two distinct lineages; a 'northern' lineage of La Palma, north Tenerife and south Tenerife populations and a 'southern' lineage of populations from Gomera and Hierro. The relationships within the northern lineage are also supported by an additional analysis of 132 restriction fragments from the remaining four enzymes. This molecular phylogeny argues for the recognition of two subspecies corresponding to the two main lineages and against the recognition of the six current subspecies which are based on inadequate 'conventional' criteria.  相似文献   

19.
20.
四个DNA片段在山茶属分子系统学研究中的应用   总被引:6,自引:1,他引:5  
选取山茶属14个组中的10组21种植物对目前常用于属内种间的4个DNA片段(ITS、waxy、trnL-F、rpL16)进行序列测定。结果表明:(1)来自叶绿体基因组的2个片段(trnL-F、rpL16)其PCR扩增和测序都很容易,但两者的进化速率都非常慢,序列矩阵只有很少信息位点(trnL-F含9个,rpL16为20个),不能提供必要的系统发育信息。(2)来自核基因组的ITS片段其PCR产物比较容易获得,但其序列的测定存在较多问题。(3)waxy是来自核基因组的另一个片段,其PCR扩增因受模板DNA的数量和质量的影响很大而有一定难度,但其进化速率较快,序列矩阵具有较多信息位点(92个),并且在山茶属是单拷贝,这对于解决山茶属这类具有许多近缘物种的类群的系统关系有重要价值。基于tsnL-F、rpL16和waxy三组数据所建分子系统树支持山茶属为一单系,但属下系统由于取样等原因有待进一步研究。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号