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Re: Air sacs in extant non-avian reptiles?


Ronald et al.,
I am obviously not a Feducciary, since I love cladistic "analysis" and I have decided to continue regarding birds as theropod descendants (eggshell microstructure has swept any recent doubts that I had), just as I did in my 1994 classification.
But on the other hand, I am not a strict cladist and have no desire to adopt Gauthier's cladistic Reptilia sensu stricto, and like most people, I regard synapsids as reptiles, and birds as a separate Class. Cladists can call such a Reptilia a "grade" (another politically-charged term??), but I prefer the traditional paraphyletic Reptilia, and only insist that it be made semi-paraphyletic by the addition of markers for its descendants (mammals and birds). In terms of information stored, a properly marked Reptilia is a clade, not a grade. Pure "cladifications" (which lack anagenetic information) are an overreaction to the old "unmarked" eclectic classifications (which lacked needed sister group information), and I think a more moderate approach will win out in the long run. There is a fruitful middle ground between "traditional eclectic" and "strictly cladistic" classification methodologies, but most people just aren't aware of it yet. You've been fighting like the Hatfields and McCoys for over 30 years now, and I think both sides are wrong (each in different ways).
------Ken Kinman
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From: Ronald Orenstein <ornstn@home.com>
Reply-To: ornstn@home.com
To: dinosaur@usc.edu
Subject: Re: Air sacs in extant non-avian reptiles?
Date: Mon, 31 Jul 2000 10:42:16 -0400

At 09:36 AM 31/07/00 -0400, ELurio@aol.com wrote:

The convention of naming groups is a highly political activity, and the
change of the term "reptile" is an example of this. The preferred term is
"amniote." A chicken is as much of a reptile as you are.


Here Mr Lurio is wrong. First of all, naming only becomes political if you
let it do so, and there is no need for this (creationists aside). But
since there seems to be a very good argument for excluding Synapsida from
Reptilia on the grounds that they were separately derived from early
tetrapods, a chicken is considerably more of a reptile than you are because
some of its ancestors were reptiles, while none of yours (or mine, or even
Mr Lurio's) were. We are, of course, all amniotes (or tetrapods, if you like).

--
Ronald I. Orenstein                           Phone: (905) 820-7886
International Wildlife Coalition              Fax/Modem: (905) 569-0116
1825 Shady Creek Court
Mississauga, Ontario, Canada L5L 3W2          mailto:ornstn@home.com


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