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1.
Evolution ; 55(6): 1198-206, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11475055

RESUMO

The bird fauna of Madagascar includes a high proportion of endemic species, particularly among passerine birds (Aves: Passeriformes). The endemic genera of Malagasy songbirds are not allied obviously with any African or Asiatic taxa, and their affinities have been debated since the birds first were described. We used mitochondrial sequence data to estimate the relationships of 13 species of endemic Malagasy songbirds, 17 additional songbird species, and one species of suboscine passerine. In our optimal trees, nine of the 13 Malagasy species form a clade. although these birds currently are classified in three different families. In all optimal trees, the sister to this endemic clade is a group of Old World warblers including both African and Malagasy birds. The endemic Malagasy songbird clade rivals other island radiations, including the vangas of Madagascar and the finches of the Galapagos, in ecological diversity.


Assuntos
DNA Mitocondrial/genética , Aves Canoras/genética , Animais , Sequência de Bases , DNA Mitocondrial/efeitos da radiação , Variação Genética , Funções Verossimilhança , Aves Canoras/classificação , Especificidade da Espécie
2.
Mol Phylogenet Evol ; 13(3): 581-95, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10620415

RESUMO

The phylogenetic relationships of the Timaliidae (babblers) and Sylviidae (warblers) have long challenged ornithologists. We focus here on three Malagasy genera currently assigned to the Timaliidae, Mystacornis, Oxylabes, and Neomixis, and on their relationships with other babblers and warblers using the sequences of two mitochondrial genes (cytochrome b and 16S rRNA). Maximum parsimony analyses show that the Malagasy "babblers" are not related to any of the other African and Asian babblers. The genus Mystacornis is neither a babbler nor a warbler. The other Malagasy "babblers" are members of warbler groups (the monophyly of the Sylviidae is not demonstrated). Oxylabes madagascariensis and Hartertula flavoviridis (we recognize Hartertula as a genus for the species flavoviridis, previously Neomixis flavoviridis) constitute, with two presumed sylviine taxa, Thamnornis chloropetoides and Cryptosylvicola randrianasoloi, a warbler radiation endemic to the island of Madagascar. The other Neomixis species (tenella, striatigula, and viridis) belong to another warbler group comprising cisticoline taxa. These results show that the Timaliidae did not disperse to Madagascar. Rather, the island has been colonized, independently, by at least two clades of warblers, probably originating from Africa, where the Sylviidae radiation has been the most extensive.


Assuntos
Aves/fisiologia , Grupo dos Citocromos b/genética , RNA Ribossômico 16S/genética , África , Animais , Ásia , Aves/classificação , Variação Genética , Genética Populacional , Madagáscar , Modelos Biológicos , Aves Canoras/classificação , Aves Canoras/genética , Aves Canoras/fisiologia
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