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1.
DNA sequences of the 5' end of the chloroplast ndhF gene for 15 species of Caryophyllaceae have been analyzed by parsimony and neighbor-joining analyses. Three major clades are identified, with little or no support for monophyly of traditionally recognized subfamilies. The first of the three major clades identified (Clade I) is constituted by part of the subfamily Paronychioideae. It includes members of the tribe Paronychieae and members of tribe Polycarpeae. The second (Clade II) contains members of the Paronychieae exclusively. Tribe Paronychieae is thus apparently polyphyletic and tribe Polycarpeae is at least paraphyletic. The third clade (Clade III) includes members of subfamilies Alsinoideae and Caryophylloideae along with the genus Spergularia. The genus Scleranthus is also part of Clade III, while Drymaria groups with the other genera of tribe Polycarpeae in Clade II. We conclude that morphological characters previously used to delimit subfamilial groupings in the Caryophyllaceae are apparently unreliable estimators of phylogeny. 相似文献
2.
Immigration and the ephemerality of a natural population bottleneck: evidence from molecular markers. 总被引:12,自引:0,他引:12
L F Keller K J Jeffery P Arcese M A Beaumont W M Hochachka J N Smith M W Bruford 《Proceedings. Biological sciences / The Royal Society》2001,268(1474):1387-1394
Population bottlenecks are often invoked to explain low levels of genetic variation in natural populations, yet few studies have documented the direct genetic consequences of known bottlenecks in the wild. Empirical studies of natural population bottlenecks are therefore needed, because key assumptions of theoretical and laboratory studies of bottlenecks may not hold in the wild. Here we present microsatellite data from a severe bottleneck (95% mortality) in an insular population of song sparrows (Melospiza melodia). The major findings of our study are as follows: (i) The bottleneck reduced heterozygosity and allelic diversity nearly to neutral expectations, despite non-random survival of birds with respect to inbreeding and wing length. (ii) All measures of genetic diversity regained pre-bottleneck levels within two to three years of the crash. This rapid recovery was due to low levels of immigration. (iii) The rapid recovery occurred despite a coincident, strong increase in average inbreeding. These results show that immigration at levels that are hard to measure in most field studies can lead to qualitatively very different genetic outcomes from those expected from mutations only. We suggest that future theoretical and empirical work on bottlenecks and metapopulations should address the impact of immigration. 相似文献
3.
This paper explores self-perceived mate value (SPMV), and its association with self-esteem, in eight cultures. 1066 participants, from 8 cultural groups in 7 countries, rated themselves on 24 SPMVs and completed a measure of self-esteem. Consistent with evolutionary theory, women were more likely to emphasise their caring and passionate romantic nature. In line with previous cross-cultural research, characteristics indicating passion and romance and social attractiveness were stressed more by respondents from individualistic cultures, and those higher on self-expression (rather than survival) values; characteristics indicative of maturity and confidence were more likely to be mentioned by those from Traditional, rather than Secular, cultures. Contrary to gender role theory, societal equality had only limited interactions with sex and SPMV, with honesty of greater significance for male self-esteem in societies with unequal gender roles. These results point to the importance of cultural and environmental factors in influencing self-perceived mate qualities, and are discussed in relation to broader debates about the impact of gender role equality on sex differences in personality and mating strategies. 相似文献
4.
Cheng Liu Guang-Rong Li Sunish Kumar Sehgal Ju-Qing Jia Zu-Jun Yang Bernd Friebe Bikram Gill 《Plant Systematics and Evolution》2010,288(3-4):149-156
The genus Dasypyrum (or Haynaldia) consists of two species, D. villosum and D. breviaristatum. However, the genomic relationships between these two species remain unclear. The objective of this study was to provide molecular phylogenic and cytological evidence on the evolutionary relationships of the genus Dasypyrum. Sequences of Chloroplast DNA (cpDNA) and α-gliadin genes both support the hypothesis that diploid D. breviaristatum is the progenitor of tetraploid D. breviaristatum, and the diploid D. villosum and D. breviaristatum evolved parallel from an ancestral species. Genomic and fluorescence in situ hybridization using ribosomal DNA and rye repetitive DNA sequence as probes also indicated that tetraploid D. breviaristatum originated from diploid D. breviaristatum. 相似文献
5.
DNA from 22 different species, accessions, cultivars and lines included in theSecale genus were analyzed by the polymerase chain reaction (PCR), using as primers five pairs of oligonucleotides derived from specific sequences. A total of 42 amplified bands were considered, and some of them appeared to be potentially useful as molecular markers for some of the analyzed groups. These amplified bands were used to generate molecular phenograms inside theSecale genus. 相似文献
6.
对采自芜湖市三个不同水体中的萼花臂尾轮虫(Brachionus calyciflorus)17个克隆的线粒体COⅠ基因和rDNAITS1序列进行的分析结果表明:萼花臂尾轮虫不同克隆间COⅠ基因序列差异百分比为0-14.0%,平均为5.1%;ITS1序列差异百分比为0-7.4%,平均为2.2%。基于COⅠ基因序列构建的分子系统树(NJ树、MP树、ML树和贝叶斯树)均支持将17个克隆划分为三个姐妹种,各姐妹种间的序列差异百分比为7.2%-14.0%。基于ITS1序列构建的同样四种分子系统树也支持将17个克隆划分为三个姐妹种,但其中的克隆HE5在姐妹种中的归属与基于COⅠ基因序列构建的分子系统树所得出的结果不同,各姐妹种间的序列差异百分比为1.9%-7.4%。混交雌体和雄体间的交配实验结果表明,轮虫各姐妹种间存在着明显的生殖隔离,克隆HE5在姐妹种中的归属应与基于COⅠ基因序列构建的分子系统树所得出的结果一致;ITS1序列进化速率较低,不宜用于轮虫姐妹种的准确甄别。COⅠ基因进化钟计算结果显示,三个姐妹种间,克隆LE9所属的姐妹种早在8百万年前便分化形成出来,HE1、HE2、HE4-7所属的姐妹种于5百万年前分化产生。 相似文献
7.
BARRIE G. M. JAMIESON 《Zoologica scripta》1986,15(2):141-155
Onychophoran sperm share striking apomorphies with sperm of oligcchaetes: the elongate, cylindrical, strongly condensed nucleus with (enchytraeid oligochaetes only) spiral keel(s); interpolation of mitochondria, which are spiral as in some microdriles, between nucleus and axoneme (autapomorphy); presence of postmitochondrial annulus; occurrence of a basal cylinder at the anterior end of the two central singlets (autapomorphy). Onychophoran sperm differ notably from oligochaete sperm: in possessing periacrosomal material; in the helical coiling, reduction, or absence of the acrosome vesicle (though acrosomal coiling occurs in leeches); in the conical subacrosomal structure contrasting with the characteristic acrosome tube of euclitellates; in the absence of a perforatorium (though these two features could be consequent on the reduction of the acrosome); in lacking a distinct padlike thickening of the anterior nuclear envelope; in possessing (external to the mutual 9 + 2 axoneme) 9 peripheral singlets and a subplasmalemmal microtubular manchette (also present in questid annelids); and in the scattered, rather than regularly arranged, peripheral glycogen of the axoneme; they also lack two additional fibres which give the characteristic tetragon of the oligochaete axoneme; and, although the centriolar triplets are disrupted, having a more complete distal centriole than in euclitellates. The remarkable similarities to euclitellate sperm, coupled with embryological similarities between Onychophora and Euclitellata, suggest that the onychophoran-euclitellate assemblage is a monophyletic group and the sister-group of the myriapod-hexapod assemblage. Wider phylogenetic implications of these findings are discussed. 相似文献
8.
Eight names in five genera Delphinium (Ranunculaceae), Lindernia and Mimulicalyx (Scrophulariaceae), Sorbus and Spiraea (Rosaceae) from China were not validly published because two gatherings were simultaneously designated as types in the protologues,
or were simultaneously cited, without indicating the type in the protologues. These eight names are validated here, with one
specimen designated as the holotype. 相似文献
9.
To facilitate marker selection in sequence-based studies on genetic diversity and symbiont selectivity in lichens we conducted a comparison of eight molecular markers in the lichen-forming fungus Lasallia pustulata and its trebouxioid photobiont. We compared mtSSU rDNA, mtLSU rDNA, MCM7, TSR1 (mycobiont) and nrITS rDNA, COX2, psbJ-L intergenic spacer, rbcL (photobiont) of 45 individuals from European populations of L. pustulata. Mycobiont and photobiont loci had congruent phylogenetic signals. Based on the results of this study we recommend the use of MCM7 and TSR1 (mycobiont), and nrITS rDNA and COX2 (photobiont). In this specific study system we found no sequence variability in the mycobiont loci EF1, nrITS rDNA, RPB1, and RPB2, which we sequenced for a subset of individuals. We had limited success amplifying GPD (mycobiont), actin and chloroplast LSU rDNA (photobiont), however, we do not rule out that these loci could be valuable markers in other species. 相似文献
10.
Relationships among the five groups of extant seed plants (cycads, Ginkgo, conifers, Gnetales, and angiosperms) remain uncertain. To explore relationships among groups of extant seed plants further and to attempt to explain the conflict among molecular data sets, we assembled a data set of four plastid (cpDNA) genes (rbcL, atpB, psaA, and psbB), three mitochondrial (mtDNA) genes (mtSSU, coxI, and atpA), and one nuclear gene (18S rDNA) for 19 exemplars representing the five groups of living seed plants. Analyses of the combined eight-gene data set (15?772 base pairs/taxon) with maximum parsimony (MP), maximum likelihood (ML), and Bayesian approaches reveal a gymnosperm clade that is sister to angiosperms. Within the gymnosperms, a conifer clade includes Gnetales as sister to Pinaceae. Cycads and Ginkgo are either successive sisters to this conifer clade (including Gnetales) or a clade that is sister to conifers and Gnetales. All analyses of the mtDNA partition and ML analyses of the nuclear partition yield very similar topologies. However, MP analyses of the combined cpDNA genes place Gnetales as sister to all other seed plants with strong bootstrap support, whereas ML and Bayesian analyses of the cpDNA data set place Gnetales as sister to Pinaceae. Maximum parsimony and ML analyses of first and second codon positions of the cpDNA partiation also place Gnetales as sister to Pinaceae. In contrast, MP analyses of third codon positions place Gnetales as sister to other seed plants, although ML analyses of third codon positions place Gnetales with Pinaceae. Thus, most of the discrepancies in seed plant topologies involve third codon positions of cpDNA genes. The likelihood ratio (LR) and Shimodaira-Hasegasa (SH) tests were applied to the cpDNA data. The preferred topology based on the LR test is that Gnetales are sister to Pseudotsuga. The SH test based on first and second codon and all three codon positions indicated that there is no significant difference between the best topology (Gnetales sister to Pseudotsuga) and Gnetales sister to a conifer clade. However, there is a significant difference between the best topology and topologies in which Gnetales are sister to the rest of the seed plants or Gnetales sister to angiosperms. 相似文献
11.
Genetic techniques are providing tools that are necessary to answer questions concerning the ecology and evolution of cnidarians that, until recently, could not be easily addressed. In developing molecular markers for cnidarians with algal symbionts (zooxanthellae), however, caution must be used to ensure the markers in question are derived from the cnidarian host and not zooxanthellae. Unless the DNA template is from asymbiotic tissue, both host and symbiont genomes are present in the DNA template and zooxanthella-specific markers are often inadvertently generated. Steps should be taken to minimize the contamination by zooxanthella DNA in the template, and the origin of the molecular marker (host or symbiont) must be verified. Including zooxanthella-specific markers in analyses for cnidarians will confound interpretations of the results as biogeographic and phylogeographic patterns of zooxanthellae do not necessarily reflect those of the host. 相似文献
12.
Abstract Identifying germplasm is an important component for efficient and effective management of plant genetic resources. This investigation was undertaken for the identification and analysis of genetic variation within 9 species of Albizzia through 33 morphological parameters, and 15 Random Amplified Polymorphic DNA (RAPD) and 17 Inter Simple Sequence Repeat (ISSR) primers. The use of selected RAPD and ISSR primers generated a total of 163 and 201 amplified DNA fragments, respectively. High frequencies of polymorphism, 95.05% for RAPD and 96.02% for ISSR, were detected. Statistical approaches were employed to construct genetic relationships by RAPD, ISSR and morphological analysis. Cluster analysis by the unweighted pair-group method (UPGMA) of Nei's similarity generated dendograms with similar topology that gave a better reflection of the diversity and affinities between species. These molecular results were comparable to main morphological characteristics. The correlation matrices generated by RAPD and ISSR markers were highly correlated (r = 0.843 at p = 1.0), thereby indicating congruence between these two marker systems. Both morphometric data and molecular markers have the potential to analyse genetic variation among the nine species of Albizzia, thus providing a major input for management strategy of plant genetic resources. 相似文献
13.
The pollinium morphology of the two members of the Asclepiadoideae, tribe Fockeeae, Fockea Endl. and Cibirhiza Bruyns, has been studied in detail and compared with that of eight genera of Marsdenieae, the tribe in which Fockea and Cibirhiza were previously accommodated and thus their putative closest relatives, as well as nine genera of Asclepiadeae. Both Fockea and Cibirhiza have several morphological characteristics in common, the most important of which is the absence of well-developed caudicula, which distinguishes them from all other genera of Asclepiadoideae known. The pollinium structure of these two genera, however, differs significantly. Whereas the pollinium of Cibirhiza consists of single pollen grains and is covered by a pollinium wall, as is typical for other Asclepiadoideae, the pollinium of Fockea consists of tetrads and is not covered by a pollinium wall, a condition otherwise typical of Secamonoideae. Fockea, however, has only two pollinia per anther, as does Cibirhiza and all other Asclepiadoideae, whereas the Secamonoideae have four pollinia per anther. Sequence data from two intergenic spacers, trnT-L and trnL-F and the trnL intron of cpDNA was analyzed. The ingroup included three species of Fockea and one species of Cibirhiza. The outgroup taxa consisted of three representatives each of Periplocoideae, and Secamonoideae and 24 species of Asclepiadoideae, including representatives of all tribes, of which eight genera belong to Marsdenieae, as outgroups. The results of the DNA analysis provide strong support for Fockeeae as a monophyletic tribe, distinct from Marsdenieae and, to the rest of the Asclepiadoideae. With the exception of pollen data, all morphological and molecular evidence clearly support recognition of the tribe Fockeeae. The occurrence of two such significantly different types of pollinia structure – characters elsewhere in the family used to distinguish subfamilies – within the small tribe Fockeeae was unexpected, and can perhaps best be understood as yet another attestment to the basal position of the Fockeeae in the nascence of the Asclepiadoideae. 相似文献
14.
C. A. Lehnebach A. Cano C. Monsalve P. McLenachan E. Hörandl P. Lockhart 《Plant Systematics and Evolution》2007,264(1-2):109-116
Laccopetalum giganteum (Ranunculaceae) is a rare endemic buttercup from the montane regions of the Peruvian Andes. The systematic position of this monotypic genus within Ranunculaceae was investigated using cpDNA matK sequence data. Our findings indicate that L. giganteum forms a highly supported clade together with Krapfia. Several morphological characters are shared by these genera; large subglobose and fleshy flowers, presence of androgynophore with a separated staminal and carpellate region and many tiny achenes. The Laccopetalum-Krapfia clade is sister to the core Ranunculus group with a high bootstrap support. The number of sepals and similar characteristics of achene morphology support an affinity of Laccopetalum with Ranunculus s.s tr. 相似文献
15.
BACKGROUND AND AIMS: Aglaonema is an important ornamental foliage plant genus, but genetic relationships among its species and cultivars have not been reported. This study analysed genetic relatedness of 54 cultivars derived from nine species using amplified fragment length polymorphism (AFLP) markers. METHODS: Initially, 48 EcoRI + 2/MseI + 3 primer set combinations were screened, from which six primer sets that showed clear scoreable and highly polymorphic fragments were selected and used for AFLP reactions. AFLP fragments were scored and entered into a binary data matrix as discrete variables. Jaccard's coefficient of similarity was calculated for all pair-wise comparisons among the 54 cultivars, and a dendrogram was constructed by the unweighted pair-group method using the arithmetic average (UPGMA). KEY RESULTS: The number of AFLP fragments generated per primer set ranged from 59 to 112 with fragment sizes varying from 50 to 565 bp. A total of 449 AFLP fragments was detected, of which 314 were polymorphic (70 %). All cultivars were clearly differentiated by their AFLP fingerprints. The 54 cultivars were divided into seven clusters; cultivars within each cluster generally share similar morphological characteristics. Cluster I contains 35 cultivars, most of them are interspecific hybrids developed mainly from A. commutatum, A. crispum or A. nitidum. However, Jaccard's similarity coefficients among these hybrids are 0.84 or higher, suggesting that these popular hybrid cultivars are genetically much closer than previously thought. This genetic similarity may imply that A. nitidum and A. crispum are likely progenitors of A. commutatum. CONCLUSIONS: Results of this study demonstrate the efficiency and ease of using AFLP markers for investigating genetic relationships of ornamental foliage plants, a group usually propagated vegetatively. The AFLP markers developed will help future Aglaonema cultivar identification, germplasm conservation and new cultivar development. 相似文献
16.
Kawai K Nikaido M Harada M Matsumura S Lin LK Wu Y Hasegawa M Okada N 《Journal of molecular evolution》2002,55(3):284-301
The family Vespertilionidae comprises the largest number of species in the order Chiroptera, and its members are distributed
over most of the world. We collected sequences of the mitochondrial NDI (NADH dehydrogenase subunit 1) gene from 38 species
as well as 20 sequences of exon28 of the vWF (von Willebrand Factor) gene and analyzed phylogenetic relationships in Vespertilionidae
using maximum-likelihood analyses and SINE (short interspersed elements) insertions. Our data strongly suggest the following:
(1) Murininae and Myotis, each of which is classified into different subfamilies, are monophyletic; (2) the monophyly of Murininae,
Myotis, Pipistrellini, and Plecotini is supported by our analyses of the NDI and nuclear vWF as well as data from SINE insertions,
while Miniopterinae was not included in this group; and (3) Rhinolophoidea (microchiroptera) is separated from all the other
microchiropteran species. Our study represents the most comprehensive phylogenetic model of Vespertilionidae to date. 相似文献
17.
The family Lemuridae includes four genera: Eulemur, Hapalemur, Lemur,Varecia. Taxonomy and phylogenetic relationships between L. catta, Eulemur and Hapalemur, and of Varecia to these other lemurids, continue to be hotly debated. Nodal relationships among the five Eulemur species also remain contentious. A mitochondrial DNA sequence dataset from the ND 3, ND 4 L, ND 4 genes and five tRNAs (Gly, Arg, His, Ser, Leu) was generated to try to clarify phylogenetic relationships w ithin the Lemuridae. Samples (n=39) from all ten lemurid species were collected and analysed. Three Daubentonia madagascariensis were included as outgroup taxa. The approximately 2400 bp sequences were analysed using maximum parsimony, neighbor-joining and maximum likelihood methods. The results support monophyly of Eulemur, a basal divergence of Varecia, and a sister-group relationship for Lemur/Hapalemur. Based on tree topology, bootstrap values, and pairwise distance comparisons, we conclude thatVarecia and Eulemur both represent distinct genera separate from L. catta. H. griseus andH. aureus form a clade with strong support, but the sequence data do not permit robust resolution of the trichotomy involving H. simus, H. aureus/H. griseus and L. catta. Within Eulemur there is strong support for a clade containing E. fulvus, E. mongoz and E. rubriventer. However, analyses failed to clearly resolve relationships among those three species or with the more distantly related E. coronatus and E. macaco. Our sequencing data support the current subspecific status of E.m. macaco and E.m. flavifrons, and that of V.v. variegata and V.v. rubra. However, tree topology and relatively large genetic distances among individual V.v. variegata indicate that there may be more phylogenetic structure within this taxon than is indicated by current taxonomy. 相似文献
18.
J R Lukacs 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》1987,45(2):97-116
Morphological variation in permanent teeth of prehistoric populations yields clues to their relationships with other prehistoric and living people. This paper documents variation in fourteen variants of the permanent tooth crown for the late Chalcolithic skeletal series from Inamgaon (1600-700 BC), an early farming settlement in western India. In comparison of the dental morphology profile at Inamgaon with American Indians and American Whites, the people of Inamgaon were found to more closely resemble American Whites. However, specific traits deviated in the direction of Amerindian dental trait frequencies, suggesting gene flow from north and east Asian populations. The dental morphology of the Inamgaon sample is similar to dental patterns characteristic of prehistoric Pakistani samples from Sarai Khola and Timargarha. However, Inamgaon and Timargarha exhibit somewhat more complex crown morphology than the Sarai Khola sample, suggesting a closer relationship between them and greater antiquity of residence in the subcontinent, in contrast to Sarai Khola sample. 相似文献
19.
Three tilapiine species belonging to the endemic Lake Malawi species flock known as' chambo' Oreochromis ( Nyasalapia ) karongae , O. (N.) lidole and O. (N.) squamipinnis and the species Oreochromis (Oreochromis) shiranus were collected from the wild. These four species were analysed at 43 enzyme loci using starch gel electrophoresis. No significant deviations from Hardy-Weinberg equilibrium were observed after correcting for multiple simultaneous testing. The expected heterozygosity ( H e ) was lowest in O. (O.) shiranus ( H e =0.082). The three chambo species had higher levels: H e =0.103 to H e =0.116. The three chambo species as a whole were polymorphic (99%) at 16 different loci sharing 10 of these in common. No fixed differences between the three chambo species were observed but highly significant allele frequency differences existed between all the chambo species. The F ST calculated for the three chambo species was 0051, closer to intra-specific than to inter-specific levels. O. (O.) shiranus could be clearly separated from all chambo species at five fixed loci. Comparison of the allozyme data from these species with five species from the same sub genera support the hypothesis that the chambo form a monophyletic group and that O. (N.) macrochir or a related species represents the sister taxon. 相似文献