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1.
Cladistics ; 34(6): 684-701, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34641640

RESUMO

Although promoted as a sociological history of then-recent systematics, David L. Hull's () Science as a Process was, in fact, heavily fictionalized, particularly in its treatment of debates between pheneticists and cladists. Hull routinely suppressed or modified information unfavourable to pheneticists, so presenting a misleading portrayal of social interactions and even of the scientific content of published discussions.

2.
Cladistics ; 30(5): 555-561, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34772270

RESUMO

Hennig (1966) recognized symplesiomorphies as homologies, and that view is logically correct under the concept of homology (homogeny) prevalent among evolutionists since 1870. Nelson and Platnick (1981) instead wanted homology to exclude symplesiomorphies for reasons that they never made clear but which certainly included opposition to Hennig. They and some of their followers, most recently Platnick (2013) and Brower and de Pinna (2013), have continued to advocate that anti-Hennigian position, often under the slogan "homology equals synapomorphy," while ironically passing themselves off as cladists and often using ambiguous or falsified citations to pretend that legitimate phylogeneticists think likewise. Such authors have seldom shown much concern for accuracy or logic, with the result that a great deal of print has been wasted. Those problems can be avoided simply by maintaining a Hennigian view and so discarding the purported equivalence of homology and synapomorphy.

3.
Cladistics ; 30(1): 5-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34781596
4.
Cladistics ; 30(2): 113-115, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34784689
5.
Cladistics ; 30(2): 116-119, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34784692
6.
Cladistics ; 30(3): 236-239, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34788972
7.
Cladistics ; 29(3): 230-232, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34798764
8.
Cladistics ; 29(3): 228-229, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34809408
9.
Cladistics ; 29(1): 13-14, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34836448
10.
Cladistics ; 28(3): 227-228, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34836447
11.
Cladistics ; 28(5): 545-547, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34844377
12.
Cladistics ; 28(6): 551-553, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34844380
13.
Cladistics ; 28(3): 231-233, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34844383
14.
Cladistics ; 28(6): 554-559, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34856736
15.
Cladistics ; 25(3): 211-230, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34879616

RESUMO

Obtaining a well supported schema of phylogenetic relationships among the major groups of living organisms requires considering as much taxonomic diversity as possible, but the computational cost of calculating large phylogenies has so far been a major obstacle. We show here that the parsimony algorithms implemented in TNT can successfully process the largest phylogenetic data set ever analysed, consisting of molecular sequences and morphology for 73 060 eukaryotic taxa. The trees resulting from molecules alone display a high degree of congruence with the major taxonomic groups, with a small proportion of misplaced species; the combined data set retrieves these groups with even higher congruence. This shows that tree-calculation algorithms effectively retrieve phylogenetic history for very large data sets, and at the same time provides strong corroboration for the major eukaryotic lineages long recognized by taxonomists.

16.
Cladistics ; 24(6): 1065-1069, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34892890

RESUMO

Grant and Kluge have recently stated that Bremer support and their own REP ("relative explanatory power"), are the only objective measures of group support. This paper discusses their claim, showing that their philosophical arguments have no basis, and that their own numerical examples actually serve to illustrate shortcomings of REP.

17.
Trends Plant Sci ; 9(10): 477-83, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15465682

RESUMO

As systematists grapple with assembling the Tree of Life, recent studies have encouraged a genomic-scale approach, obtaining DNA sequence data for entire nuclear, plastid or mitochondrial genomes for a few exemplar taxa. Some have proclaimed that this comparative genomic strategy heralds the end of incongruence in phylogeny reconstruction. Although we applaud the use of many genes to resolve phylogenetic patterns, there is a significant caveat. In spite of, or even because of, the abundant data per taxon, whole-genome sequencing for a few exemplars can provide completely resolved and strongly supported, but incorrect, evolutionary reconstructions. We provide a conspicuous example that includes Amborella, the putative sister of all other extant angiosperms, highlighting the limits of phylogenetics when whole genomes are used but taxon sampling is poor.


Assuntos
Genoma de Planta , Magnoliopsida/classificação , Magnoliopsida/genética , Filogenia , Códon/genética , DNA Mitocondrial/genética , DNA de Plantas/genética , Reprodutibilidade dos Testes
18.
Am J Bot ; 91(12): 2102-18, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21652358

RESUMO

B-function MADS-box genes play crucial roles in floral development in model angiosperms. We reconstructed the structural and functional implications of B-function gene phylogeny in the earliest extant flowering plants based on analyses that include 25 new AP3 and PI sequences representing critical lineages of the basalmost angiosperms: Amborella, Nuphar (Nymphaeaceae), and Illicium (Austrobaileyales). The ancestral size of exon 5 in PI-homologues is 42 bp, typical of exon 5 in other plant MADS-box genes. This 42-bp length is found in PI-homologues from Amborella and Nymphaeaceae, successive sisters to all other angiosperms. Following these basalmost branches, a deletion occurred in exon 5, yielding a length of 30 bp, a condition that unites all other angiosperms. Several shared amino acid strings, including a prominent "DEAER" motif, are present in the AP3- and PI-homologues of Amborella. These may be ancestral motifs that were present before the duplication that yielded the AP3 and PI lineages and subsequently were modified after the divergence of Amborella. Other structural features were identified, including a motif that unites the previously described TM6 clade and a deletion in AP3-homologues that unites all Magnoliales. Phylogenetic analyses of AP3- and PI-homologues yielded gene trees that generally track organismal phylogeny as inferred by multigene data sets. With both AP3 and PI amino acid sequences, Amborella and Nymphaeaceae are sister to all other angiosperms. Using nonparametric rate smoothing (NPRS), we estimated that the duplication that produced the AP3 and PI lineages occurred approximately 260 mya (231-290). This places the duplication after the split between extant gymnosperms and angiosperms, but well before the oldest angiosperm fossils. A striking similarity in the multimer-signalling C domains of the Amborella proteins suggests the potential for the formation of unique transcription-factor complexes. The earliest angiosperms may have been biochemically flexible in their B function and "tinkered" with floral organ identity.

19.
Cladistics ; 20(6): 558-578, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34892961

RESUMO

The transition to a vermiform body shape is one of the most important events in animal evolution, having led to the impressive radiation of Bilateria. However, the sister group of Bilateria has remained obscure. Cladistic analyses of morphology indicate that Ctenophora is the sister group of Bilateria. Previous analyses of SSU rRNA sequences have yielded conflicting results; in many studies Ctenophora forms the sister group of Cnidaria + Bilateria, but in others the ctenophores group with poriferans. Here we re-examine the SSU sequence by analyzing a dataset with 528 metazoan + outgroup sequences, including almost 120 poriferan and diploblast sequences. We use parsimony ratchet and jackknife methods, as well as Bayesian methods, to analyze the data. The results indicate strong phylogenetic signals for a cnidarian + bilaterian group and for the comb jellies to have branched off early within a group uniting all epithelial animals [(Ct,(Cn,Bi))]. We demonstrate the importance of inclusive taxonomic coverage of ribosomal sequences for resolving this problematic part of the metazoan tree: topological stability increases dramatically with the addition of taxa, and the jackknife frequencies of the internal nodes uniting the lineages [(Cn,Bi) and ((Ct,(Cn,Bi))] also increase. We consider the reconstructed topology to represent the current best hypothesis of the interrelationships of these old lineages. Some morphological features supporting alternative hypotheses are discussed in the light of this result.

20.
Mycol Res ; 107(Pt 8): 901-16, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14531615

RESUMO

A data set with 1551 fungal sequences of the small subunit ribosomal RNA has been analysed phylogenetically. Four animal sequences were used to root the tree. The parsimony ratchet algorithm in combination with tree fusion was used to find most parsimonious trees and the parsimony jackknifing method was used to establish support frequencies. The full-length consensus tree, of the most parsimonious trees, is published and jackknife frequencies above 50% are plotted on the consensus tree at supported nodes. Until recently attempts to find the most parsimonious trees for large data sets were impractical, given current computational limitations. The parsimony ratchet in combination with tree fusion was found to be a very efficient method of rapid parsimony analysis of this large data set. Parsimony jackknifing is a very fast and efficient method for establishing group support. The results show that the Glomeromycota are the sister group to a monophyletic Dikaryomycota. The majority of the species in the Glomeromycota/Dikaryomycota group have a symbiotic lifestyle--a possible synapomorphy for a group 'Symbiomycota'. This would suggest that symbiosis between fungi and green plants evolved prior to the colonization of land by plants and not as a result of the colonization process. The Basidiomycotina and the Ascomycotina are both supported as monophyletic. The Urediniomycetes is the sister group to the rest of the Basidiomycotina successively followed in a grade by Ustilaginomycetes, Tremellomycetes, Dacrymycetales, Ceratobasidiales and Homobasidiomycetes each supported as monophyletic except the Homobasidiomycetes which are left unsupported. The ascomycete node begins with a polytomy consisting of the Pneumocystidomycetes, Schizosaccharomycetes, unsupported group with the Taphrinomycetes and Neolectales, and finally an unnamed, monophyletic and supported group including the Saccharomycetes and Euascomycetes. Within the Euascomycetes the inoperculate euascomycetes (Inoperculata) are supported as monophyletic excluding the Orbiliomycetes which are included in an unsupported operculate, pezizalean sister group together with Helvellaceae, Morchellaceae, Tuberaceae and others. Geoglossum is the sister group to the rest of the inoperculate euascomycetes. The Sordariomycetes, Dothideomycetes, Chaetothyriomycetes and Eurotiomycetes are each highly supported as monophyletic. The Leotiomycetes and the Lecanoromycetes both appear in the consensus of the most parsimonious trees but neither taxon receives any jackknife support.


Assuntos
Fungos/classificação , Fungos/genética , Filogenia , DNA Fúngico/genética , DNA Ribossômico/genética , RNA Ribossômico/genética , Análise de Sequência de DNA
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