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Diversification of Ramphastinae (Aves, Ramphastidae) prior to the Cretaceous/Tertiary boundary as shown by molecular clock of mtDNA sequences
Provedor de dados: 74
Autores: Nahum,Laila Alves; Pereira,Sérgio Luiz; Campos Fernandes,Flora Maria de; Russo Matioli,Sergio; Wajntal,Anita.
Partial cytochrome b and 12S rDNA mitochondrial DNA sequences of eight representatives of the Ramphastidae family were analyzed. We applied the linearized tree method to identify sequences evolving at similar rates and estimated the divergence times among some of the taxa analyzed. After excluding Ramphastos tucanus and Capito dayi from our data set, the remaining taxa presented a constant rate of DNA substitution, and branch lengths could be re-estimated with a clock constraint using the maximum likelihood method. Branch lengths were calibrated assuming that Galliformes and Piciformes split around 100 million years ago (mya). Our results indicate that Ramphastinae, and probably Capitoninae, diverged from other Piciformes in the Late Cretaceous (~82 mya),...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Divergence times; K/T; Mass extinction; Cytochrome b; 12S rDNA; Paleogeography; Phylogeny.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000400003