marc sosef Marc.Sosef at PROSEA.PT.WAU.NL
Mon Jun 16 14:37:38 CDT 1997

Dear Taxacomers,

With growing amazement I have been following the recent discussion on
paraphyly. It now seems to focus upon the question whether or not an
ancestral species becomes 'extinct' or not upon a speciation event. Let me
cite two parts from my recent article in Taxon 46, p. 79: "Hennig's
definition of a species is no longer regarded as being in line with
evolutionary reality." "The elements defined by Hennig as species since have
been called 'internodons' and proved useful as building blocks of a more
rigorous species concept: the composite species (Kornet, 1993)."

Hennig made an -artificial- construct in order to smoothen his theory of
monophyletic classification. He saw the dark clouds and thought this was a
nice way out, but indeed Thomas Lammers is right when he so fiercefully
stresses that it is not congruent with NATURE.

Again, I would like to stress that, when you have all began to see that
Hennig's ideas should be abandoned, you cannot discuss monophyletic
classification within the context of Linnaean nomenclature. A lot of the
discussion I have seen so far, misses the point, because it tries to force
our present concept of taxa (all species belong to a genus and all genera
belong to a family) upon a monophyletic system which is IMPOSSIBLE (see my
article in Taxon). Monophyletic classification needs its own nomenclature as
it is structurally different from Linnaean classification. A monophyletic
system will accept an (ancestral) species that does belong to a certain
'family' but not to any of is 'genera'. Anyone who discusses monophyletic
classifcation and uses Linnaean caterogies does, in my view, not deserve
further attention.

Marc S.M. Sosef
Dept. of Plant Taxonomy
Wageningen Agricultural University
P.O. Box 8010
6700 ED Wageningen
The Netherlands
Phone: (31) 317 483180
fax: (31) 317 484917
e-mail: marc.sosef at

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