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1.
Phylogenetic relationships of Greek cyprinidae: molecular evidence for at least two origins of the Greek cyprinid fauna. 总被引:4,自引:0,他引:4
A phylogeny of the main cyprinid species that live in Greece was based on the complete mitochondrial cytochrome b gene (1140 bp). The great diversity of the Greek cyprinid fauna, with at least 4 different lineages of barbins, 1 of gobionins, and 10 of leuciscinids, was confirmed. The validity and composition of the genera Tropidophoxinellus and Pachychilon were demonstrated. Likewise, the close phylogenetic relationships of genera Vimba, Blicca, and Abramis, as well as Telestes, Chondrostoma, and Phoxinellus, were established. Moreover, Pseudophoxinus beoticus was found to be closely related to Phoxinellus rather than to other Pseudophoxinus species. The most interesting outcome of our analyses was the existence of at least two different origins of the Greek cyprinid fauna. Most of the Greek cyprinids were directly related to the Danubian (i.e., central European) ichthyofauna. However, we found at least four cases of a close phylogenetic relationship between Greek and Iberian endemic species. 相似文献
2.
The phylogenetic relationships among all Iberian endemic cyprinids were inferred using the complete nucleotide sequence of the cytochrome b gene. The inferred molecular phylogeny included representatives from Central European, Asian and North African species, and is highly congruent with previous phylogenies based on osteological characters. Iberian cyprinids were grouped into only five, very speciose lineages (with the exception of the monotypic Anaecypris): Barbus, Luciobarbus, Chondrostoma, Leuciscus and Anaecypris. The existence of such a relatively small number of Iberian cyprinid lineages can be explained by the historical isolation of the Iberian Peninsula. North African and Asian barbels are the sister group of Iberian Luciobarbus, supporting a south-eastern route of colonization of the Iberian Peninsula for this subgenus. With leuciscins, Anaecypris hispanica was considered a relict species as it could not be related to any other Iberian cyprinid. The phylogenetic relationships among the main lineages of Iberian cyprinids based on cytochrome b sequence data supported the traditional division of the Cyprinidae into two subfamilies: Cyprininae and Leuciscinae. 相似文献
3.
The cytochrome b gene as a phylogenetic marker: the limits of resolution for analyzing relationships among cichlid fishes 总被引:12,自引:0,他引:12
The mitochondrial cytochrome b (cyt-b) gene is widely used in systematic studies to resolve divergences at many taxonomic levels. The present study focuses mainly
on the utility of cyt-b as a molecular marker for inferring phylogenetic relationship at various levels within the fish family Cichlidae. A total
of 78 taxa were used in the present analysis, representing all the major groups in the family Cichlidae (72 taxa) and other
families from the suborders Labroidei and Percoidei. Gene trees obtained from cyt-b are compared to a published total evidence tree derived from previous studies. Minimum evolution trees based on cyt-b data resulted in topologies congruent with all previous analyses. Parsimony analyses downweighting transitions relative to
transversions (ts1:tv4) or excluding transitions at third codon positions resulted in more robust bootstrap support for recognized
clades than unweighted parsimony. Relative rate tests detected significantly long branches for some taxa (LB taxa) which were
composed mainly by dwarf Neotropical cichlids. An improvement of the phylogenetic signal, as shown by the four-cluster likelihood
mapping analysis, and higher bootstrap values were obtained by excluding LB taxa. Despite some limitations of cyt-b as a phylogenetic marker, this gene either alone or in combination with other data sets yields a tree that is in agreement
with the well-established phylogeny of cichlid fish.
Received: 11 October 2000 / Accepted: 26 February 2001 相似文献
4.
Lukas Rüber Maurice Kottelat Heok Hui Tan Peter KL Ng Ralf Britz 《BMC evolutionary biology》2007,7(1):38
Background
Paedocypris, a highly developmentally truncated fish from peat swamp forests in Southeast Asia, comprises the world's smallest vertebrate. Although clearly a cyprinid fish, a hypothesis about its phylogenetic position among the subfamilies of this largest teleost family, with over 2400 species, does not exist. Here we present a phylogenetic analyses of 227 cypriniform taxa, including 213 cyprinids, based upon complete mitochondrial DNA cytochrome b nucleotide sequences in order to determine the phylogenetic position of Paedocypris and to study the evolution of miniaturization among cyprinids. 相似文献5.
Genetic Affinities Within the Herring Gull Larus argentatus Assemblage Revealed by AFLP Genotyping 总被引:2,自引:0,他引:2
de Knijff P Denkers F van Swelm ND Kuiper M;Port of Rotterdam Gull Study Group 《Journal of molecular evolution》2001,52(1):85-93
To date, the taxonomic status of circumpolar breeding populations of the Herring Gull Larus argentatus, the Lesser Black-backed Gull Larus fuscus, and the closely related Yellow-legged Gull Larus cachinnans has been based on differences or similarities in phenotype, morphology, and feeding and premating behavior. To shed some
new light on the many taxonomic uncertainties surrounding these taxa, we describe the results of a large DNA study based on
comparing the distribution of 209 biallelic markers among 109 gulls, representing 11 gull taxa of the Herring Gull assemblage
and the Common Gull Larus canus. A detailed phylogenetic analysis failed to show clustering of individuals into groups representing either geographic origin
or phenotype. Alternatively, birds were grouped into taxa defined on the basis of phenotype and geographic origin or phenotype
alone. Genetic analyses revealed significantly different genetic distances between all pairs of taxa. However, based on these
genetic distances, again no consistent phylogenetic tree could be constructed. Analysis of molecular variance indicated that
about 77% of the total genetic variability among these gulls could be explained by within-taxon differences. Only 23% of the
total genetic variability was due to genetic differences between taxa, irrespective of their species or subspecies status.
Although this seems to challenge the current taxonomic treatment of the herring gull assemblage, our results are too premature
and too incomplete to recommend a drastic change.
Received: 27 January 2000 / Accepted: 18 September 2000 相似文献
6.
The genus Chrysolina consists of specialized phytophagous leaf-beetles (Coleoptera, Chrysomelidae) with feed on several plant families. There
is no explicit phylogenetic hypothesis available for this genus, which includes 65 subgenera and more than 400 species with
a wide distribution. We obtained 839-bp sequence data from the 16S rDNA and cytochrome oxidase subunit I (COI) mitochondrial
genes. Thirty Chrysolina taxa representing eight host–plant affiliations, two species of the closely related genus Oreina, and two outgroups were sampled. These data sets were used separately and combined to obtain the mitochondrial cladogram of
the group using maximum-parsimony and maximum-likelihood criteria. The results were compared to current proposals for Chrysolina systematics that are based on morphological, ecological, and karyological data. The trees obtained were in the most part
congruent with the proposed ancestral association of Chrysolina to Lamiaceae based on chromosome number in several lineages. A minimum of five host-plant switches from the ancestral state
inferred at the family level and two at the subclass level suggests the absence of parallel evolution of beetles and their
host plants. Another switch leading to oligophagy at the family level was deduced to have occurred in the lineage of the subgenus
Chrysolina s.str.
Received: 22 May 1998 / Accepted: 16 September 1998 相似文献
7.
Nuclear and Nucleomorph SSU rDNA Phylogeny in the Cryptophyta and the Evolution of Cryptophyte Diversity 总被引:5,自引:0,他引:5
The plastid-bearing members of the Cryptophyta contain two functional eukaryotic genomes of different phylogenetic origin,
residing in the nucleus and in the nucleomorph, respectively. These widespread and diverse protists thus offer a unique opportunity
to study the coevolution of two different eukaryotic genomes within one group of organisms. In this study, the SSU rRNA genes
of both genomes were PCR-amplified with specific primers and phylogenetic analyses were performed on different data sets using
different evolutionary models. The results show that the composition of the principal clades obtained from the phylogenetic
analyses of both genes was largely congruent, but striking differences in evolutionary rates were observed. These affected
the topologies of the nuclear and nucleomorph phylogenies differently, resulting in long-branch attraction artifacts when
simple evolutionary models were applied. Deletion of long-branch taxa stabilized the internal branching order in both phylogenies
and resulted in a completely resolved topology in the nucleomorph phylogeny. A comparison of the tree topologies derived from
SSU rDNA sequences with characters previously used in cryptophyte systematics revealed that the biliprotein type was congruent,
but the type of inner periplast component incongruent, with the molecular trees. The latter is indicative of a hidden cellular
dimorphism (cells with two periplast types present in a single clonal strain) of presumably widespread occurrence throughout
cryptophyte diversity, which, in consequence, has far-reaching implications for cryptophyte systematics as it is practiced
today. 相似文献
8.
A.D. Shutov H. Braun Yu.V. Chesnokov Ch. Horstmann I.A. Kakhovskaya H. Bäumlein 《Journal of molecular evolution》1998,47(4):486-492
The development of seeds as a specialized organ for the nutrition, protection, and dispersal of the next generation was an
important step in the evolution of land plants. Seed maturation is accompanied by massive synthesis of storage compounds such
as proteins, starch, and lipids. To study the processes of seed storage protein evolution we have partially sequenced storage
proteins from maturing seeds of representatives from the gymnosperm genera Gnetum, Ephedra, and Welwitschia—morphologically diverse and unusual taxa that are grouped in most formal systems into the common order Gnetales. Based on
partial N-terminal amino acid sequences, oligonucleotide primers were derived and used for PCR amplification and cloning of
the corresponding cDNAs. We also describe the structure of the nuclear gene for legumin of Welwitschia mirabilis. This first gnetalean nuclear gene structure contains introns in only two of the four conserved positions previously characterized
in other spermatophyte legumin genes. The distinct phylogenetic status of the gnetalean taxa is also reflected in a sequence
peculiarity of their legumin genes. A comparative analysis of exon/intron sequences leads to the hypothesis that legumin genes
from Gnetales belong to a monophyletic evolutionary branch clearly distinct from that of legumin genes of extant Ginkgoales
and Coniferales as well as from all angiosperms.
Received: 5 June 1997 / Accepted: 31 March 1998 相似文献
9.
Stefan Hiendleder Heidrun Lewalski Rudolph Wassmuth Axel Janke 《Journal of molecular evolution》1998,47(4):441-448
The complete mitochondrial DNA (mtDNA) molecule of the domestic sheep, Ovis aries, was sequenced, together with part of the mtDNA of a specimen representing the other major O. aries haplotype group. The length of the complete ovine mtDNA presented is 16,616 nucleotides (nt). This length is not absolute,
however, due to heteroplasmy caused by the occurrence of different numbers of a 75-nt-long tandem repeat in the control region.
The sequence data were included in analyses of intraspecific ovine molecular differences, molecular comparisons with bovine
mtDNAs, and phylogenetic analyses based on complete mtDNAs. The comparisons with bovine mtDNAs were based on the central domains
of the ovine control regions, representing both major ovine haplotype groups, and the corresponding domains of Bos taurus and B. indicus. The comparisons showed that the difference between the bovids was 1.4 times greater than the intraspecific ovine difference.
These findings suggest that the strains of wild sheep from which domestic sheep originated were more closely related than
were the B. primigenius subspecies which gave rise to B. indicus and B. taurus cattle. Datings based on complete mtDNAs suggest that the bovine and ovine lineages diverged about 30 million years before
present. This dating is considerably earlier than that proposed previously.
Received: 5 September 1997 / Accepted: 5 May 1998 相似文献
10.
Partial sequences of two mitochondrial genes, the 12S ribosomal gene (739 bp) and the cytochrome b gene (672 bp), were analyzed in hopes of reconstructing the evolutionary relationships of 11 leporid species, representative
of seven genera. However, partial cytochrome b sequences were of little phylogenetic value in this study. A suite of pairwise comparisons between taxa revealed that at
the intergeneric level, the cytochrome b gene is saturated at synonymous coding positions due to multiple substitution events. Furthermore, variation at the nonsynonymous
positions is limited, rendering the cytochrome b gene of little phylogenetic value for assessing the relationships between leporid genera. If the cytochrome b data are analyzed without accounting for these two classes of nucleotides (i.e., synonymous and nonsynonymous sites), one
may incorrectly conclude that signal exists in the cytochrome b data. The mitochondrial 12S rRNA gene, on the other hand, has not experienced excessive saturation at either stem or loop
positions. Phylogenies reconstructed from the 12S rDNA data support hypotheses based on fossil evidence that African rock
rabbits (Pronolagus) are outside of the main leporid stock and that leporids experienced a rapid radiation. However, the molecular data suggest
that this radiation event occurred in the mid-Miocene several millions of years earlier than the Pleistocene dates suggested
by paleontological evidence.
Received: 23 April 1998 / Accepted: 14 May 1998 相似文献