RE: Shoehorning (Augury and Alvarezsauria)

["Jaime A. Headden" <qilongia@yahoo.com>]

Ken Kinman (kinman@hotmail.com) quoted Norman Platnick (), a research
arachnologist at the AMNH:

<"It seems that there are at least two motivations behind this movement,
which I'm ashamed to say was originated by two herpetologists from the
U.S., Kevin De Queiroz and Jacques Gauthier.  One motivation, seemingly,
is just to find some way to salvage non-monophyletic groups like Reptilia
and Dinosauria, so that herpetologists are not inconvenienced by increased
understanding of amniote interrelationships."

  This goes back to the pre-1990's debate that still suggested that
Dinosauria was polyphyletic. Based on the use of feathers that Thulborn,
and Bakker and Galton used, there has been much work to resolve this
contention. Ever since Gauthier and Padian, in fact, and the work of
Thulborn and von Huene, Paul, Bakker foremost, Novas, and Sereno,
Dinosauria was considered to be as evenly polyphyletic as much as
monophyletic, but not any more. Carroll's 1988 book Vertebrate
Paleontology still had a Thecodontia section within which Dinosauria was
mentioned as a possible monophyly.

  You will no longer find a reference worth it's salt in vertebrate
paleontology post-1991 that suggests that Dinosauria is polyphyletic or
_anything_ other than monophyletic. If this is the substance of Platnick's
statement, then _duh_! Okay, no attack on an otherwise excellent
researcher and well-known entomologist, also curator at the AMNH and
former Entomology Chair, but to suggest an underlying motivation to any
cladistic result is just bad form, and furthering it worse still. The work
of Gauthier has been built up and improved upon, and even he will say
this, and now the work of Norell et al., Novas, Sereno, Holtz, etc., work
to create increasingly complex and involved matrices including every
conceivable character relating between two taxa (provided it's not
size-related or functional) and then just adding taxa like there no
mañana. Unpublished work by Rauhut and Mortimer also help to elaborate
saurischian monophyly, but this is beside the point.

  Platnick's info and opinion are seriously dated, and I would be
intrigued to know the context and date of the quote. Bulldogging this to
pull down cladistic methodology in conflict to non-cladistic is similar,
and is not scientific.

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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