Artikel zur Phylogenese

Hi,

manchmal stösst man im Netz auf sehr vielversprechende Artikel, die aber leider Otto dem Normal-Aquarianer nicht zugänglich sind. Das Thema Phylogenese, also die wissenschaftliche Klärung der Abstammungs- und Verwandschaftsgeschichte ist für sowas wie das Amazonasgebiet super interessant. Im folgenden Artikel geht es zwar um den afrikanischen Grabensee, aber ich kann mir vorstellen, dass dieses Ergebnis auch einige Anregungen für uns bietet. Kommt jemand an diese wissenschaftlichen Arbeiten ran und kann sie mal für uns bewerten? (oder mir einfach mailen?)

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Phylogenetic relationships of the Lake Tanganyika cichlid tribe Lamprologini: The story from mitochondrial DNA
Day, JJ, S Santini & J Garcia-Moreno, 2007. Phylogenetic relationships of the Lake Tanganyika cichlid tribe Lamprologini: The story from mitochondrial DNA. Molecular Phylgenetics and Evolution 45: 29–642.

Abstract

The Lamprologini are the most species-rich and diverse tribe of Lake Tanganyika cichlids, comprising around 90 described species. We reconstruct the most complete (70 species) mtDNA phylogeny to date for this tribe, based on NADH dehydrogenase subunit 2 (ND2 1047 bp) and the non-coding control region (874 bp) and examine the degree to which mtDNA trees are good proxies for species trees. Phylogenetic relationships are assessed using Bayesian inference, maximum likelihood and maximum parsimony to determine the robustness of relationships. The resulting topologies are largely congruent and only the tree produced by an unpartitioned BI analysis is rejected using the non-parametric likelihood-based AU test. The trees are remarkably balanced, with two major clades consistently recovered in all analyses and with reasonable support. A smaller clade of deep-water species is also recovered. Overall support is good, when compared to some groups that have undergone adaptive radiation and rapid lineage formation. The much-expanded phylogeny of the group helps resolve the placement of some previously problematic taxa, such as Neolamprologus moori, highlighting the importance of greater taxonomic sampling. The results include a number of divergent placements of closely related species, and the following genera Neolamprologus, Lamprologus, Julidiochromis, Telmatochromis are not monophyletic, with alternative hypotheses consistent with traditional taxonomy providing a significantly worse fit to the data. We find several examples of divergent mtDNA taxa sequences of presumed closely related species. This could be due to incorrect taxonomy or to the failure of the mtDNA to reflect species relationships and may support the hypothesis that speciation within this group has been facilitated by introgressive hybridisation.


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