Of uropods and isopod crustacean trees: A comparison of 'groundpattern' and empirical cladistic methods
Contents
Abstract
In a recent paper, Wägele (1994) attacked widely-used computer-assisted cladistic methods for estimating phylogenetic trees, specifically those used in isopod phylogeny. This paper evaluates his alternative method, based on the allegedly "Hennigian" determination of groundpatterns, and compares it with empirical cladistic methods. Wägele's groundpattern method for determining phylogenies is logically circular, because it finds monophyletic groups that were assumed in the assembly of the groundpatterns. The method is also unscientific because it does not test the hypotheses that it proposes. Trees obtained using this method are likely to be unparsimonious because characters are not evaluated globally. As examples of how Wägele's method fails, and how cladistic methods are more rigorous, three cases from isopod phylogeny are discussed in some detail: the distribution of character states in the uropods, the sister groups of the Protognathiidae, and the relationships of taxa in the Microcerberidae.