Catarrhine phylogeny and classification: Principles, methods and comments

Abstract

In recent years, zoological systematists have engaged in heated debate over methods of phylogeny reconstruction and classification, but little of this interaction has penetrated the anthropological literature. I have summarized part of it here, concentrating on the cladistic method of phylogeny analysis and the relationship of classification to its underlying phylogeny, with examples and comments from the evolutionary history of catarrhine primates. Phylogeny may be broken down into “cladogeny”, the study of branching points and phyletic linkages among taxa, and “scenarios”, or interpretive reconstructions of adaptation and ancestry. In cladogeny analysis, fossils are treated in the same way as modern taxa, with their stratigraphic age considered only in special circumstances. In a scenario, the identification of actual ancestor taxa may be attempted in a probabilistic manner only if specific criteria are fulfilled. Classifications must closely reflect the group's cladogeny, but several methods are available to assign ranks to taxa and to vary the final hierarchical pattern. These theoretical postulates are applied to the catarrhines, resulting in several cladograms of intertaxon relationship, a more extrapolative phylogeny diagram and some alternative classifications, including the insertion of new ranks.