paraphyletic evolution

Ken Kinman kinman at HOTMAIL.COM
Sat Feb 5 11:08:59 CST 2000


Curtis,
    I was delightfully "stunned" when you started challenging another strict
cladist (Tom DiBenedetto).  You might become a cladisto-eclecticist yet.
    If most speciation is budding (paraphyletic), then you cannot cut a
continuous tree of life without creating paraphyletic groups.  The only
reason cladistic classifications work is because extinction and a
fragmentary fossil record have left us with huge gaps in that tree of life.
Hennigian assumptions and methodologies work most of the time, UNTIL the
gaps start getting smaller (and this naturally happens at species level more
quickly than at higher taxonomic levels).
     The philosophy that lies behind the Kinman System is to retain as much
information as possible, while minimizing the numbers (and arbitrariness) of
cuts in the tree of life.  The coding packs in lots of information without
destabilizing formal nomenclature, and the Kinman markers explicitly show
where the inevitable paraphyletic cuts have been made (thus
cross-referencing useful taxonomic "files", rather than splitting them into
uselessness).
    Tom and many other strict cladists want to define paraphyletic species
out of existence, and therefore they open themselves up to charges of
"essentialism".  Therefore, taken to "essentialistic" extremes, strict
cladism is not only impractical and counterproductive, but they actually
come to believe sister species have an objective reality.  In my opinion,
this blinds them to the increasing arbtrariness of strictly cladistic
classifications (different from much of the old eclectic arbritrariness, but
just as counterproductive).
     Cladisto-eclecticism isn't totally perfect, but I think it minimizes
arbitrariness, and maximizes information and stability.  I think cladistic
"analysis" is the greatest thing since slice bread, but purely cladistic
classifications (which Ernst Mayr cleverly named "cladifications") are now
counterproductive (or eventually become so).  Hennig's long-term
contributions should (and hopefully will) lie in his more rigorous cladistic
analytical techniques, not in a paraphylophobic paradigm of endless
splitting and classificatory instability.
                             -----Ken Kinman
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