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Mark Siddall mes at zoo.toronto.edu
Tue Jun 21 10:43:53 EST 1994

Paddy wrote:

>The word 'monophyly' has a variety of meanings within the community of 
>systematists.  The word 'holophyly' has a single meaning.  That provides 
>the word 'holophyly' with a significant advantage.

I agree to an extent, however, the term monophyly DID have a singular
meaning until Ashlock, and currently still has a singular meaning in MOST
circles.  My concern is the fact that the largest portion of the
systematic community applies monophyly as wholly distinct from paraphyly
and ignores holophyly as simply redundant with monophyly such that when a
minority resurrects "holophyly", we require clarification of what is meant
by "monophyly".  This confusion is uneccessary given that we all know what
we are talking about anyway.  

>The following is a quote about this particular issue:
>'Although scientists not involved in a particular terminological squabble 
>are likely to dismiss it as being "merely semantic", more than conceptual 
>clarity is involved in such disputes.  By and large it is easier to say 
>what one wants to say in one's own terminology than in the terminology 
>preferred by one's opponents, even when on occasion their are fairly 
>precise mappings ...  Getting one's preferred terminology adopted 
>strongly biases the game in one's favor.  ...  If the terminology of a 
>particular research program is adopted, subsequent generations will 
>assume that this particular program succeeded, no matter how much the 
>meanings of these terms may have been transmuted in the process.'

I'm not so sure that this is applicable.  The issue at hand is not one of
competing schools of systematic thought.  In fact, we are not even
debating what it is we are referring to.  What I call monophyly you call
holophyly; what I call paraphyly, you call paraphyly, what I call
polyphyly, you call polyphyly.  So there is no substantive theoretical,
methodological or philosophical issue at stake here.  I contend that it is
semantic.  The source, I believe, of the semantic issue IS a philosophical
difference in which you would recognize paraphyletic classifications,
whereas I would not.  I recognize your right to make such a judgement, and
am not arguing that I ought to be dictatorial about classification. 
Expanding the term monophyly to include paraphyly, however, obscures this
philosophical difference and does nothing to further the process of
healthy scientific discourse.  

>and also still in respect of this particular issue
>'The dispute continues undiminished to the present.'
>This was not written by a protozoologist.  Clearly, not everyone concurs 
>that the matter is inactive.
>Tolerance of diversity is a virtue.

As is clarity of thought and purpose.  I _am_ tolerant of the diversity of
opinion regarding what deserves to recognized in taxonomic schemes (the
real substantive issue here).  I regard the murky waters of what
"holophyly" does to monophyly to be contrary to greeting that diversity as
it runs the risk of preventing us from knowing precisely what one is
talking about.

I recognize that my arguing for rejecting "holophyly" on the grounds that
most systematists don't use it smacks of tyrrany by the majority.  Yet I
do not believe that anyone's substantive opinions are being trodden on
since the real debate of whether to recognize paraphyly can continue
regardless of the terminology.  


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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