terms

Mark Siddall mes at zoo.toronto.edu
Sun Jun 19 23:56:32 EST 1994



Regarding the mono/holo/paraphyly issue, I've had to rehash this a number of 
times.

Why does everyone remember Ashlock's work and not Farris' very sound 
refuations of it?
"Haekel, History and Hull"
"Hennig defined monophyly"

I will post the full citations tomorrow.  Please read them if you really 
think all that had to be said was said by Ashlock.

In fact, the term monophyly was defined by Haekel and his usage can be show 
be identical to that of Hennig's, which was NOT at all vague.

The ONLY rationale for the holophyly point of view is to make paraphyly
a subset of monophyly and thereby legitimize it.  

The fact remains that monophlyetic groups are defined by synapomorphy,
paraphyletic groups are defined by symplesiomorphy, and polyphyletic
groups are defined by convergence.

Neither symplesiomorphy or convergence are acceptable as evidence of
common ancestry.

If you want to keep archaic classification schemes that are not
phylogenetic by allowing paraphyly for the naming of higher taxa, then 
just say so and forget the now-dead semantic argument for holophyly.
And forget trying to legimitimize it.  Don't forget that Ashlock openly
admitted that his argument was intended as a defense of the old
synthetic evolutionary-taxonomy school.  Surely no one would argue
that we should go back to that school of thought and abandon empiricism!

The rest of the systematic community uses monophyly, paraphyly and
polyphyly... period.  I suppose it's no surprise that protistan 
systematists hold to paraphyly given that Protozoa is the ultimate
paraphyletic group!  The only thing that distinguishes them is what they
are NOT, not what they ARE.  (i.e., eukaryotic not plant, not animal,
not fungus).

Just how long will the protozoologists stand outside of the rest of the
systematic community???

Mark
-- 
Mark E. Siddall                "I don't mind a parasite...
mes at vims.edu                    I object to a cut-rate one" 
Virginia Inst. Marine Sci.                     - Rick
Gloucester Point, VA, 23062



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