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Re: cladobabble.../Some clarification... (long)



In a message dated 97-11-19 11:36:33 EST, martz@holly.ColoState.EDU writes:

<< Having read
 Gauthier's paper on phylogenetic taxonomy, I am still at a loss to
 understand (or at least agree with) the philosophical basis for
 considering a monophyletic group to be any more real then a
 paraphyletic group >>

This is a point I've been trying to get across for several years now, to
little avail.

If taxon A is monophyletic and includes taxon B, which is also monophyletic,
then whatever reality there is for A and B must also extend to their set
difference, A-B, which is a paraphyletic taxon (because it excludes the
descendants of A that are in B). Accepting >only< monophyletic groups as
valid taxa is, to be blunt, nothing more than dogmatic (and irritating
besides). The idea of taxonomy is to give names to scientifically interesting
groups of organisms, and limiting the formal naming process to monophyletic
taxa implies that these are the only interesting groups. Thus some people now
feel compelled to employ such needless circumlocutions as "non-avian
dinosaurs" when discussing the animals known to most other people simply as
"dinosaurs." Some paraphyletic groups are just as, if not more, interesting
than either the smallest monophyletic group they are included in or the
monophyletic groups that are excluded from them, and such groups should have
formal scientific names.