Artikel Andreas Schmidt-Rhaesa


Andreas Schmidt-Rhaesa Centrum für Naturkunde, University of Hamburg,
Martin-Luther-King-Platz 3, 20146 Hamburg, Germany



Peter Ax and the System of Metazoa


Besides his contributions to phylogenetic systematics, to research on flatworms and to the interstitial fauna and environment, the three volume book series ‘Multicellular Animals’ (German title: Das System der Metazoa) are one of the main outputs of Peter Ax´s scientific career. This article tries to reconstruct how the interest in metazoan systematics grew in Peter Ax. Additionally, some process in animal systematics, which took place around the publication date of Ax´s books is reviewed to estimate its importance. Finally, some selected hypotheses from the ‘Multicellular Animals’ are compared with current hypotheses.
Between 1995 and 2001, Peter Ax published three volumes of his book ‘Das System der Metazoa’ (Ax 1995, 1999, 2001) (English translation ‘Multicellular Animals’: Ax 1996, 2000, 2002). These volumes constitute a unique approach to systematize the multicellular animals according to the principles of phylogenetic systematics. These principles were developed by Willi Hennig (e.g. Hennig 1950, 1966) and elaborated by Ax (1984, 1988). This text is the attempt to outline Peter Ax´s relation to metazoan systematics by asking three questions: 1. Where did Ax´s interest in metazoan systematics come from? 2. How are the three books embedded in a historical context? 3. How did selected phylogenetic hypotheses develop since the publication of the books?


Peter Ax | Phylogenetic Systematics | Metazoan Relationships | Phylogenetic Hypotheses