[Taxacom] systematics eggs in one basket

[Richard Zander]

Information from both molecular and morphological studies must be dealt
with, most of us agree, Curtis. But just how is the puzzle.

I figure that morphological characters are good clues in the context of
the Modern Synthesis, with which one can infer adaptive strategies and
the like. It's like using Newton's laws in the mesocosm, such laws work
in the world we live in. Neutral evolution is either working at the
molecular level or is dealt with by standard concepts of bottlenecking
and drift. Recognizing species and higher categories that document or
hypothesize functional evolution or otherwise hypothetically explain the
phenome and environment interaction are important.

Molecular phylogenetics is a kind of relentless pedigree study based on
the generally acceptable idea that neutral base changes (and the like)
track events of genetic isolation. It should not work well with groups
that are not liable to the biological species concept (plants.
Molecular tracking goes right down to the nut of tokogenetic or
panmictic populations, theoretically. But do we want base classification
on that? How do we take the good and slough the bad?

Many of us have an answer: recognize paraphyly when appropriate.
Example: If morphology and good analysis of functional evolution give
(AB)C and molecular pedigree says (AC)B, we can, if we eschew strict
monopyly in this case, say that AB is a taxon with coherent unifying
evolutionary strategies (nonteleological of course) and C is a divergent
lineage coming off (sharing an ancestor with) a genetically isolated
population. 

Thus any family discovered deeply embedded in a lineage of another
family can be continued to be recognized at the family if it represents
a new evolutionary direction. 

Strict monophyly is a classificatory short-cut having the attraction of
ease-of-paradigm. Inferring a process of functional evolution involves
eventually a huge amount of work in population and reproductive biology,
biophysics (exactly what does this plant use this structure for?), and
biosystematics. We make a good start but thirty years ago got
sidetracked.

Remember biosystematics? I think it is time for a rededication.

-----Original Message-----
From: taxacom-bounces at mailman.nhm.ku.edu
[mailto:taxacom-bounces at mailman.nhm.ku.edu] On Behalf Of Curtis Clark
Sent: Thursday, February 01, 2007 9:38 PM
To: taxacom at mailman.nhm.ku.edu
Subject: Re: [Taxacom] systematics eggs in one basket

On 2007-02-01 11:25, John Grehan wrote:
> (and I would explicitly say a morphologist who
> does not include molecular studies).

A morphologist who eschews molecular studies is as bad as a molecular 
systematist who eschews morphology.

-- 
Curtis Clark                  http://www.csupomona.edu/~jcclark/
Web Coordinator, Cal Poly Pomona                 +1 909 979 6371
Professor, Biological Sciences

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