[Taxacom] classifications (was: no subject)

Mario Blanco mblanco at flmnh.ufl.edu
Thu Apr 2 18:10:36 CDT 2009

   Ken, as a "strict cladist", I do not like classifications that allow 
paraphyletic groups. If I want to see "ancestor-descendant information" 
I can simply consult the latest phylogenetic hypotheses on the group of 
interest, as some have repeatedly said.

   And, do you really think you can convince everyone (even most people) 
to use a moderately paraphyletic classification like yours? There will 
always be many people like me, who prefer a strictly cladistic 
classification. And there will always be a lot of people that prefer 
much more paraphyletic classifications (e.g., accepting Reptilia), just 
because it is easier for them to remember. That is why you are wrong 
when you say that the APG could "very, very easily make their 
classification almost universally acceptable" by allowing some 
paraphyletic families.

    I like a monophyletic Ericaceae as it is in the APG system. If you 
want to use your paraphyletic classification, that's fine; I will keep 
using the APG one. What is the problem with that? As long as we 
explicitly indicate which system we use, we will always know what 
organisms you are talking about, and we can concentrate on learning more 
about their biology instead of wasting time on fighting for competing 
mental constructs (classifications).

    By the way, this is to discuss "issue No. 2" in Richard's post, 
which does a great job at distinguishing the three separate lines of 
discussion in this thread. And I agree with your other two points.


From:     kennethkinman at webtv.net (Kenneth Kinman)

     Well, I believe that a totally phylogenetic classification that is
broken by a single paraphyletic break is still totally phylogenetic in
an informational sense.  Using my {{exgroup}} markers you can still hook
the two resulting cladograms into a single large cladogram.  The
phylogenetic information is still 100%, but you add in some
ancestor-descendant information as a bonus.  
      But just for the sake of argument, let's say some might consider
the paraphyletic break reducing it from 100% to 90% phylogenetic (in
some philosophical way).  If traditionalists start using these "90%"
phylogenetic classifications, then almost everyone will be using highly
phylogenetic classifications that are identical or with very minor
differences.  All those very unphylogenetic classifications will
disappear.  You don't even have to meet them half-way.  Virtually all
classifications would become 90-100% phylogenetic, would become more
stable and more useful, and the differences would be very minor.  We
would be working together rather than working at cross purposes.
     The APG (Angiosperm Phylogeny Group) could VERY, VERY easily make
their classifications almost universally acceptable by (1) partially
reversing a couple cases of their excessive lumping at ordinal level;
and (2) allow some paraphyletic families instead of stubbornly
insistently that they must all be holophyletic.  For example, a
paraphyletic Ericaceae is a very small price to pay, and an
{{Epacridaceae}} exgroup marker allows us to keep 100% of the
phylogenetic information anyway.
       --------Ken Kinman
Mario wrote:
if "strict cladists" agreed to "allow occasional paraphyletic breaks",
we would no longer be "strict cladists". And I am puzzled as to how you
can view non phylogenetic classifications as "more phylogenetic".
 From Kenneth Kinman:
  "But until strict cladists agree to allow occasional paraphyletic
breaks, the destabilization and arguments will continue. Why they
wouldn't want to do this really puzzles me, as it would make all
classifications more phylogenetic."

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