Before revision: History upWilli Hennig 1972 upPeter Chalmers Mitchell in 1920 upRobert John Tillyard The original methods used in cladistic analysis and the school of taxonomy derived from the work of the German entomologist Willi Hennig, who referred to it as phylogenetic systematics (also the title of his 1966 book); the terms "cladistics" and "clade" were popularized by other researchers.
After revision: butHistory upWilli Hennig 1972 upPeter Chalmers Mitchell in 1920 upRobert John Tillyard The original methods used in cladistic analysis and the school of taxonomy derived from the work of the German entomologist Willi Hennig, who referred to it as phylogenetic systematics (also the title of his 1966 book); the terms "cladistics" and "clade" were popularized by other researchers.