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	Provedor de dados Naturalis (3) Zoologia (1) Autor Jenner, Ronald A. (2) Almeida,Waltécio de Oliveira (1) Amorim,Dalton de Souza (1) Christoffersen,Martin Lindsey (1) Garraffoni,André Rinaldo Senna (1) Silva,Gustavo Sene (1) Telford, Maximilian J. (1) Mais... Palavra-chave Metazoa (4) Phylogeny (3) Bilateria (2) 18S rDNA (1) Absence/presence coding (1) Boolean logic (1) Character coding (1) Character state identity (1) Cladistics (1) Clitellata (1) Ecdysozoa (1) Enterocoela (1) Gnathostomulida (1) Metazoan cladistics (1) Molecular synapomorphy (1) Morphological cladistics (1) Nemertea (1) Nonadditive binary coding (1) Platyhelminthes (1) Polychaeta (1) Mais... Tipo do documento Article / Letter to the editor (3) Info:eu-repo/semantics/article (1) Ano 2004 (1) 2003 (1) 2002 (2) País Netherlands (3) Brazil (1) Idioma Inglês (1)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 4 Primeira ... 1 ... Última Boolean logic and character state identity: pitfalls of character coding in metazoan cladistics Naturalis Jenner, Ronald A.. A critical study of the morphological data sets used for the most recent analyses of metazoan cladistics exposes a rather cavalier attitude towards character coding. Binary absence/presence coding is ubiquitous, but without any explicit justification. This uncompromising application of Boolean logic in character coding is remarkable since several recent investigations have nominated absence/presence coding as the most problematic coding method available for standard cladistic analysis. Moreover, the prevalence of unspecified “absence” character states in the published data sets introduces a discrepancy between the theoretical foundations of phylogenetic parsimony and current practices in metazoan cladistics. Because phylogenetic parsimony assumes... Tipo: Article / Letter to the editor Palavras-chave: Metazoan cladistics; Metazoa; Character coding; Character state identity; Boolean logic; Nonadditive binary coding; Absence/presence coding. Ano: 2002 URL: http://www.repository.naturalis.nl/record/534396 Towards a phylogeny of the Metazoa: evaluating alternative phylogenetic positions of Platyhelminthes, Nemertea, and Gnathostomulida, with a critical reappraisal of cladistic characters Naturalis Jenner, Ronald A.. This paper critically assesses all morphological cladistic analyses of the Metazoa that were published during the last one and a half decades. Molecular and total evidence analyses are also critically reviewed. This study focuses on evaluating alternative phylogenetic positions of the ‘acoelomate’ worms: Platyhelminthes, Nemertea, and Gnathostomulida. This paper consists of two parts. In Part I, all recently proposed sister group hypotheses and the supporting synapomorphies for these phyla are evaluated. Discrepancies in the treatment of corresponding characters in different cladistic analyses are identified, and where possible, resolved. In Part II, the overall phylogenetic significance across the Metazoa of all characters relevant for placing the... Tipo: Article / Letter to the editor Palavras-chave: Platyhelminthes; Nemertea; Gnathostomulida; Metazoa; Bilateria; Phylogeny; Morphological cladistics; 18S rDNA; Total evidence. Ano: 2004 URL: http://www.repository.naturalis.nl/record/534337 Cladistic analyses of molecular characters: The good, the bad and the ugly Naturalis Telford, Maximilian J.. Molecular cladistics is an emerging discipline in which any heritable molecular characteristic can be treated in the same way that a traditional cladist would treat a morphological character. Taxa that share specific derived molecular characters (synapomorphies) are recognized as more closely related to each other than they are to other taxa without these characters. Herein, I point out that molecular characters are susceptible to the same problems of homoplasy and uncertain polarity as morphological characters and illustrate these problems (and point towards a general solution) using examples from the Metazoa. Tipo: Article / Letter to the editor Palavras-chave: Molecular synapomorphy; Phylogeny; Rare genomic change; RGC; Metazoa; Cladistics. Ano: 2002 URL: http://www.repository.naturalis.nl/record/534289 Polychaeta, Annelida, and Articulata are not monophyletic: articulating the Metameria (Metazoa, Coelomata) Zoologia Almeida,Waltécio de Oliveira; Christoffersen,Martin Lindsey; Amorim,Dalton de Souza; Garraffoni,André Rinaldo Senna; Silva,Gustavo Sene. Polychaetes are metameric worms recognized for having parapodia, chaetae, and nuchal organs. Some authors have extended the Annelida to include Pogonophora, Echiura, and Clitellata. These suggestions are insufficient to generate a monophyletic group. They do not take into account two very large and important clades that in a cladistic analysis at a higher level are shown to be nested within the Annelida: the Ecdysozoa (arthropods and related taxa) and Enterocoela (deuterostomes and related taxa). Evolutionary histories of most characters across metazoan phyla are still very poorly known. Metameres and coeloms have been considered homoplastic in the literature, and yet the homeobox genes responsible for the expression of metamerism and of paired appendages,... Tipo: Info:eu-repo/semantics/article Palavras-chave: Bilateria; Clitellata; Ecdysozoa; Enterocoela; Metazoa; Phylogeny; Polychaeta. Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752003000100006 Registros recuperados: 4 Primeira ... 1 ... Última

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