Hennig, Emil Hans Willi (The Father of Cladism)


Emil Hans Willi Hennig was a German systematist and entomologist. As a specialist in Diptera, he published a fundamental treatise on dipteran larvae and taxonomic monographs on several families. Hennig, however, is best known for his theoretical and methodological contributions to biological systematics. Indeed, he is considered the founder of phylogenetic systematics, or cladistics. Hennig articulated a method by which the evolutionary relationships of organisms (phylogeny) can be reconstructed and this reconstruction is subsequently turned into a hierarchical classification. This method contrasted with the mainstream approach to biological systematics adopted till the 1960s, but eventually succeeded to replace it, although in a modified version in respect to Hennig's original outline. Hennig's phylogenetic systematics has heavily impacted other biological disciplines, especially biogeography.

Keywords: cladistics; classification; phylogeny; species; tree of life

Figure 1.

Willi Hennig. Courtesy of Prof. Dr. Michael Schmitt, Greifswald. © Prof. Dr. Michael Schmitt.

Figure 2.

A page from a notebook dated 1944, documenting Willi Hennig's early studies on phylogenetics. Courtesy of Dr. Gerd Hennig, Tübingen, with permission of Brill, Leiden. © Brill.



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Further Reading

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Schmitt M (2013) From Taxonomy to Phylogenetics. Life and work of Willi Hennig. Leiden‐Boston: Brill.

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Minelli, Alessandro(Jan 2014) Hennig, Emil Hans Willi (The Father of Cladism). In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0025061]