Dissecando a sistemática filogenética hennigiana

Abstract

Willi Hennig [1913-1976], a shy german dipterologist, during the end of World War II, as a war prisioner, writes and organizes the sketches that will constitute his book Grundzüge einer Theorie der Phylogenetischen Systematik (Foundations of a Theory of Phylogenetic Systematics), published in 1950, in german. The work is expanded and translated into english in 1966, with the title Phylogenetic Systematics. It appears in a very specific context, that of the complex coexistence of different systematic traditions in germany in the first half of the 20th century. Its content is dense, it involves a complex pantheon of intellectuals from different areas, whose ideas are articulated in a difficult writing style. In addition, the work has a strong philosophical burden, from where most of the problems of the philosophy of biological systematics were rescued or created. Despite its idiosyncrasies, this work unleashes the development of all the diversity of current research programs aimed at investigating the biota's kinship relations. The present work, based on analytical tools of the philosophy and history of biology, dissects the hennigian phylogenetic systematics, investigating the epistemological peculiarities that help to elucidate its theoretical-methodological coupling. The results of this investigation showed that the hennigian phylogenetic systematics: a) differently from some narratives (which reduce it as only one method), according to the ontological-epistemological panorama constructed by the author of the work, it has a theoretical dimension that does not only exist, as it is, from different paths, unavoidable; b) it has an object of investigation that suffers from “ontological amphibology”, insofar as it is the very representation of the unique and obligatory mereology (according to the hennigian panorama) existing between lineage and semaphoront, the entities that are related genealogically and need be explained genealogically; c) has at least 83 premises, including premises of a priori ontological nature, premises based on other theories and methodological premises, all of which are organized in subdivisions throughout the text; d) it has an extremely complex theoretical-methodological organization, and poorly presented in didactic terms, where a myriad of concepts, components of an eccentric theoretical vocabulary, are interconnected in a way that is difficult to abstract, which is why both this theoretical and methodological organization, in addition to the latter's connection to its pertinent inferential logic, are discussed in detail and graphically represented in this work.