Original paper

Problematic issues of cladistics: 22. HENNIG'S understanding of phylogenetic trees

Reif, Wolf-Ernst


The interpretation of HENNIG'S (1966) branching diagrams is still controversial. They serve to clarify the method of Phylogenetic Systematics. Recently DAYRAT (2005) has interpreted them as phylogenetic diagrams and claimed that they cannot (contra HENNIG!) be transformed into Venn diagrams. It is shown here that HENNIG'S Phylogenetic Systematics is a method to classify Recent taxa, and that HENNIG'S diagrams are dendrograms that provide exactly the same information as Venn diagrams. Attention is called upon the facts that DARWIN'S proposal of a genealogical classification and HENNIG'S idea of a classification that mirrors the phylogenetic process cannot be realized. Only static entities (taxa and clades) can be classified, but not processes.


phylogenetic treesPhylogeneticVenn diagrams