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Sun Apr 10 17:33:32 EST 2005


"Ashlock's definition was less restrictive than Hennig's because Ashlock
took 'monophyly' to include both Hennig's monophyly and Hennig's
paraphyly.  Hennig explained 'A monophylytic group is a group of species
descended from a single "stem" species, and which includes all species
descended from this species.'  To Hennig, a paraphyletic group was one
united only by symplesiomorphies... according to Ashlock, Haekel's wording
matched Hennig's definition - not Ashlock's own - in the crucial
requirement that that a monophylyetic group comprise all of the
descendants of it's common ancestor."

In relation to Haekel having recognized Reptilia as monophyletic and that
being justification of the author of the term having recognized paraphyly
as part of monophyly Farris points out that Haekel's "Monophyletischer
Stammbaum der Organism" depicts Reptilia as a monophyletic group in the
strict Hennigian sense NOT in the Ashlockian sense.

Though Ashlock pointed out that 40% of the 400 higher taxa recognized by
Haekel were paraphyletic, this has nothing to do with what Haekel meant by
monophyletic... it was simply an indication that Haekel did not require
monophyly of higher taxa!  For that matter, Haekel DID recognize Protozoa
even though he had decided that they were POLYphyletic!




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