Description: (Biologist)
Willi Hennig, a German biologist and zoologist, is renowned as the pioneer of phylogenetic systematics. His groundbreaking contributions to evolution and systematics transformed the understanding of the natural order of organisms. Hennig focused on dipterans and introduced terms such as synapomorphy and paraphyly. His concept of the "auxiliary principle" highlighted the significance of apomorphic traits in determining relationships between species. Additionally, Hennig's progression rule in cladistics suggested that the most primitive species are situated at the earliest part of a group's range, generating debates within the scientific community.