(1) The Journal of the Willi Hennig Society. (2) The scientific discipline of classifying organisms according to the doctrine of Willi Hennig's 1966 book. (3) The belief that the organisation of taxa into groups can only be done by the identification of synapomorphies for that group.
A phylogenetic approach that stresses the importance of understanding the evolutionary relevance of the characters that are studied. A particular systematic approach to building evolutionary trees and interpreting their meaning.
Method of classifying organisms into groups (taxa) based on 'recency of common descent ' as judged by the possession of shared derived (i.e., not primitive) characters.