[Taxacom] More precise sound bite

Kenneth Kinman kennethkinman at webtv.net
Fri Mar 27 10:11:35 CDT 2009

Dear All, 
        Well, to be fair to the strict cladists (their
intentions are good), I would add three words to Paul's sound bite (in
order to more precisely reflect the real differences):    The denial
of paraphyly is a denial of "important aspects of" history. 

      They don't really deny history, they are just overly obsessed
with one aspect (the branching patterns).  There is other important
information that needs to be reflected in order to produce complete,
useful, and relatively stable classifications.  As a cladist
(non-strict), I am also fascinated with more and more synapomorphies and
dividing the Tree of Life.  HOWEVER, some synapomorphies are far more
fundamental and important than others, and ranks help us reflect that
(and ranks also yield classifications that are more balanced).    
          Example:   The separation of ear
ossicles from the jawbone (between therapsids and mammals) is an
extremely important step toward the development of acute mammalian
hearing. It is fortuitous that mammary glands and hair developed along
this same lineage, but they evolved more gradually (and don't fossilize
well), so it makes sense to peg the beginning of Class Mammalia on the
equally important character of ear structure. This is reflected in the
presence of external ear "pinnae" which gather sound. And the fact that
mammals' external ears are rarely lost (as in some sea mammals) make
mammals instantly recognizable. All of this contrasts with the HUGE
importance strict cladists have attached to the synapsid skull (one
hole, while diapsids have two), and this gives them an excuse to rip the
mammal-like reptiles out of Class Reptilia. Their fear of paraphyletic
taxa results in too much emphasis on some synapomorphies and too little
on others.  Thus their cladifications lack important information, are
less useful, and are often less stable.  

Paul wrote: 
kennethkinman at webtv.net (Kenneth Kinman) wrote: 
  Conclusion. The most important kinds of complexity, be >they
structural, or otherwise, are where paraphyletic cuts in >the Tree of
Life are most useful (to both scholars and lay people). 

To put it in a sound byte: The denial of paraphyly is the denial of

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