Re: Why all the fuss? (flame-free)

["Ken Kinman" <kinman@hotmail.com>]

Mike,
     Perhaps the following is the third difference which slipped your mind 
;-)  , but it BY FAR the most important and fundamental difference which 
causes more difficulties than all the others put together:  (3) Whether or 
not formal paraphyletic groups should be recognized.  [Added Note:  I just 
read David's post, and we agree that this is a really big deal].
     This is at the very heart of the difference between strictly cladistic 
(phylogenetic) taxonomy and those who are not strict cladists (many of whom 
*do* use cladistic analysis).  Michael Benton and countless others recognize 
paraphyletic groups, but use the traditional endings (like Saurischia), so 
my standardized endings are just a very minor issue that are not at the 
heart of the debate at all.
    It all boils down to whether phylogeny is the *sole* criterion for 
classification, which would force us to *always* formally embed subclades 
within larger clades.  The price of doing classification in such a strictly 
cladistic manner is very high and as Benton's paper last year pointed out, 
it will probably only get worse (although strict cladists clearly disagree 
and believe it will eventually get better).
    Therefore we have two choices: (1) strict cladism (for which we may pay 
an steep price); or (2) a hybrid system similar to the one used by Benton in 
his 1997 book.  I think most of us would agree that the third alternative, 
the old traditional eclecticism, is no longer adequate (untestable since 
paraphyletic groups are not marked as such, and sister group information is 
lost).  If we are going to formally remove Aves from Reptilia, some kind of 
explicit marker must be left behind to avoid the loss of information and 
testability.
    So that is the heart of the matter.  Is the banning of formal 
paraphyletic groups worth the price (especially in instability and 
confusion)?  And the answer to that depends on how stiff you think that 
price will be.  Benton obviously thinks the price is too high and will only 
rise as time goes on, while strict cladists believe it will be a shorter 
term problem and that we will not have to continue paying that price 
indefinitely.  I obviously think a modest amount of explicit paraphyly would 
avert a lot of these problems, and could give us the best of both worlds, 
but others clearly disagree.
               -------Ken

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