Willi Hennig

Willi Hennig
Willi Hennig in 1972
Born
Emil Hans Willi Hennig

(1913-04-20)20 April 1913
Died5 November 1976(1976-11-05) (aged 63)
EducationState Museum of Zoology, Dresden, University of Leipzig
Known forCladistics, Hennig's progression rule
SpouseIrma Wehnert
AwardsLinnean Medal (1974), honorary doctorate from the Freie Universität Berlin
Scientific career
FieldsTaxonomy, Entomology
InstitutionsKaiser-Wilhelm-Gesellschaft, Berlin-Dahlem; State Museum of Natural History, Stuttgart

Emil Hans Willi Hennig (20 April 1913 – 5 November 1976) was a German biologist and zoologist who is considered the founder of phylogenetic systematics, otherwise known as cladistics.[1][2][3] In 1945 as a prisoner of war, Hennig began work on his theory of cladistics, which he published in German in 1950, with a substantially revised English translation published in 1966. With his works on evolution and systematics he revolutionised the view of the natural order of beings.[4][5] As a taxonomist, he specialised in dipterans (true flies).

Hennig coined the key terms synapomorphy, symplesiomorphy, and paraphyly. He also asserted, in his "auxiliary principle", that "the presence of apomorphous characters in different species 'is always reason for suspecting kinship [i.e., that species belong to a monophyletic group], and that their origin by convergence should not be presumed a priori' (Hennig, 1953). This was based on the conviction that 'phylogenetic systematics would lose all ground on which it stands' if the presence of apomorphous characters in different species were considered first of all as convergences (or parallelisms), with proof to the contrary required in each case."[6] This has been viewed as an application of the parsimony principle to the interpretation of characters, an important component of phylogenetic inference.[7]

He is also remembered for Hennig's progression rule in cladistics, which argues controversially[8] that the most primitive species are found in the earliest, central part of a group's area.

  1. ^ Dupuis, C (November 1984). "Willi Hennig's Impact on Taxonomic Thought". Annual Review of Ecology and Systematics. 15 (1): 1–25. doi:10.1146/annurev.es.15.110184.000245. ISSN 0066-4162.
  2. ^ Brower, Andrew V. Z. (2013). "Willi Hennig at 100". Cladistics. 30 (2): 224–225. doi:10.1111/cla.12057.
  3. ^ Wheeler, Q (17 April 2013). "Heed the father of cladistics". Nature. 496 (7445). Nature Research: 295–296. doi:10.1038/496295a. ISSN 1476-4687. PMID 23598324.
  4. ^ Palmer, Douglas. Evolution: the story of life. University of California Press: Berkeley. 2009. p. 13
  5. ^ Engel, Michael S.; Kristensen, Niels P. (7 January 2013). "A History of Entomological Classification". Annual Review of Entomology. 58 (1): 585–607. doi:10.1146/annurev-ento-120811-153536. ISSN 0066-4170. PMID 23317047.
  6. ^ Hennig, W. 1966. Phylogenetic Systematics. University of Illinois Press, Urbana.
  7. ^ Farris, J. S. 1983. The logical basis of phylogenetic analysis. Pp.7-36 in Advances in Cladistics, vol. 1 (eds. N. I. Platnick and V. A. Funk). Columbia Iniversity Press, NY.
  8. ^ Briggs, J.C. (1987). Biogeography and Plate Tectonics. Elsevier. p. 11. ISBN 978-0-08-086851-6.