Utility of nuclear DNA intron markers at lower taxonomic levels: Phylogenetic resolution among nine Tragelaphus spp.

Date
2005
Authors
Willows-Munro S.
Robinson T.J.
Matthee C.A.
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Phylogenetic relationships among the nine spiral-horn antelope species of the African bovid tribe Tragelaphini are controversial. In particular, mitochondrial DNA sequencing studies are not congruent with previous morphological investigations. To test the utility of nuclear DNA intron markers at lower taxonomic levels and to provide additional data pertinent to tragelaphid evolution, we sequenced four nuclear DNA segments (MGF, PRKCI, SPTBN, and THY) and combined these data with mitochondrial DNA sequences from three genes (cytochrome b, 12S rRNA, and 16S rRNA). Our molecular supermatrix comprised 4682 characters which were analyzed independently and in combination. Parsimony and model based phylogenetic analyses of the combined nuclear DNA data are congruent with those derived from the analysis of mitochondrial gene sequences. The corroboration between nuclear and mtDNA gene trees reject the possibility that genetic processes such as lineage sorting, gene duplication/deletion and hybrid speciation account for the conflict evident in the previously published phylogenies. It suggests rather that the morphological characters used to delimit the Tragelaphid species are subject to convergent evolution. Divergence times among species, calculated using a relaxed Bayesian molecular clock, are consistent with hypotheses proposing that climatic oscillations and their impact on habitats were the major forces driving speciation in the tribe Tragelaphini. © 2005 Elsevier Inc. All rights reserved.
Description
Keywords
mitochondrial DNA, animal, antelope, article, biological model, cell nucleus, classification, comparative study, DNA sequence, genetics, intron, methodology, molecular evolution, molecular genetics, nucleotide sequence, phylogeny, species difference, statistical analysis, statistical model, Animals, Antelopes, Base Sequence, Cell Nucleus, Data Interpretation, Statistical, DNA, Mitochondrial, Evolution, Molecular, Introns, Likelihood Functions, Models, Genetic, Molecular Sequence Data, Phylogeny, Sequence Analysis, DNA, Species Specificity, Antelope, Bovidae, Tragelaphus
Citation
Molecular Phylogenetics and Evolution
35
3