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1.
Proc Biol Sci ; 273(1595): 1729-32, 2006 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-16790404

RESUMO

The Asian countries chronically infected with avian influenza A H5N1 are 'global hotspots' for biodiversity conservation in terms of species diversity, endemism and levels of threat. Since 2003, avian influenza A H5N1 viruses have naturally infected and killed a range of wild bird species, four felid species and a mustelid. Here, we report fatal disseminated H5N1 infection in a globally threatened viverrid, the Owston's civet, in Vietnam, highlighting the risk that avian influenza H5N1 poses to mammalian and avian biodiversity across its expanding geographic range.


Assuntos
Conservação dos Recursos Naturais , Virus da Influenza A Subtipo H5N1 , Infecções por Orthomyxoviridae/veterinária , Viverridae/virologia , Animais , Biodiversidade , Aves/virologia , Feminino , Virus da Influenza A Subtipo H5N1/classificação , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/virologia , Filogenia , Viverridae/anatomia & histologia , Viverridae/fisiologia
2.
Syst Biol ; 54(6): 865-94, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16282167

RESUMO

Adaptive convergence in morphological characters has not been thoroughly investigated, and the processes by which phylogenetic relationships may be misled by morphological convergence remains unclear. We undertook a case study on the morphological evolution of viverrid-like feliformians (Nandinia, Cryptoprocta, Fossa, Eupleres, Prionodon) and built the largest morphological matrix concerning the suborder Feliformia to date. A total of 349 characters grouped into four anatomical partitions were used for all species of Viverridae and viverrid-like taxa plus representatives of the Felidae, Hyaenidae, Herpestidae, and one Malagasy mongoose. Recent molecular phylogenetic analyses suggest that viverrid-like morphotypes appeared independently at least three times during feliformian evolution. We thus used a synthetic molecular tree to assess morphological evolutionary patterns characterizing the viverrid-like taxa. We examined phylogenetic signal, convergence and noise in morphological characters using (a) tree-length distribution (g1), (b) partitioned Bremer support, (c) RI values and their distribution, (d) respective contributions of diagnostic synapomorphies at the nodes for each partition, (e) patterns of shared convergences among viverrid-like taxa and other feliformian lineages, (f) tree-length differences among alternative hypotheses, and (g) the successive removal of convergent character states from the original matrix. In addition, the lability of complex morphological structures was assessed by mapping them onto the synthetic molecular tree. The unconstrained morphological analysis yielded phylogenetic groupings that closely reflected traditional classification. The use of a synthetic molecular tree (constraint) combined with our thorough morphological investigations revealed the mosaics of convergences likely to have contributed to part of the historical uncertainty over viverrid classification. It also showed that complex morphological structures could be subjected to reversible evolutionary trends. The morphological matrix proved useful in characterizing several feliformian clades with diagnostic synapomorphies. These results support the removal from the traditionally held Viverridae of several viverrid-like taxa into three distinct families: Nandiniidae (Nandinia), Prionodontidae (Prionodon), and the newly defined Eupleridae (including Cryptoprocta, Fossa, Eupleres plus all "mongoose-like" Malagasy taxa). No clearly "phylogenetically misleading" data subsets could be identified, and the great majority of morphological convergences appeared to be nonadaptive. The multiple approaches used in this study revealed that the most disruptive element with regards to morphological phylogenetic reconstruction was noise, which blured the expression of phylogenetic signal. This study demonstrates the crucial need to consider independent (molecular) phylogenies in order to produce reliable evolutionary hypotheses and should promote a new approach to the definition of morphological characters in mammals. [Constrained analysis; convergence; evolutionary scenario; Feliformia; morphology; noise; phylogenetic signal; phylogeny; Viverridae.].


Assuntos
Anatomia Comparada/métodos , Evolução Biológica , Pesos e Medidas Corporais/classificação , Filogenia , Viverridae/classificação , Animais , Biometria , Carnívoros/anatomia & histologia , Carnívoros/classificação , Especiação Genética , Modelos Estatísticos , Viverridae/anatomia & histologia
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