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Re: Fixing dinosaurian carnivour question



Since when was there any question that dino-groupies couldn't be included?  Who 
is
this List for anyhow?  Big hint:  those of us who don't have subscriptions to 
all
the journals where the original papers come out, along with those who do.  I am
not in favor of excluding Aves, but do we want to turn this into a discussion of
which is the better flooring for their cages, Nature or Science?     I agree 
that
I haven't seen too many refer to dinosaurs as "extinct avians", but those who do
are rather strident, while even ignoring all of the dinosaurs that had nothing 
to
do with the lineage that led to birds.  On the other hand, those who "love" to
call our prehistoric faves "non-avian dinosaurs" do include some prominent names
in the field.  I can't get through any publication from the American Museum, 
much
less their fourth floor, without getting beaten over the head repeatedly with 
that
appellation.  Well, if you don't want to call it "love," then don't.  But no
matter how lonely it gets on those digs, and how many beers you end your day 
with,
watch it on loving those non-human primates or any other extant synapsids.
Considering the diversity  of extant mammals, should we be *precise* by calling
ourselves non-rodent, non-chiropteran placentals?  Scientific precision can get 
a
bit long-winded.  I do realize that there is a spectrum of changes that leads 
from
what we might unequivocally call a dinosaur to what can be called a bird.  Where
in this sequence does the tail disappear get traded for a pygostyle, and when 
does
the semilunate fuse to the metacarpals?  Did maniraptor dinosaurs have a hinged
maxilla (do all modern birds?)  Are there enough distinctly bird features that
modern Avians can be called dinosaur descendants  rather than dinosaurs?  I 
don't
mind being told that the answer is no, but then how is criteria determined to
separate these Classes?
Frank, the Dino-groupie
{I certainly do not want to denigrate the importance of pre-KT birds, and wish
there was a lot more information available about them, but how popular would 
this
list be without the big scaley beasts?)

"Thomas R. Holtz, Jr." wrote:

> At 08:30 AM 5/26/99 -0700, Frank wrote:
>
> >Well, if you really want to be paleo-politically correct,  I suppose that
> >birds may be dinosaurs.
>
> If you want to be *SCIENTIFIC*, then we must regard birds as dinosaurs.  On
> the other hand, if all you are interested in is a chat room for
> "dino-groupies", then go ahead and exclude Aves.
>
> >I know there are those who love to refer to
> >(classic)dinosaurs as extinct avians,
>
> Actually, there are very few who would do that: George Olshevsky's taxonomy
> includes some (but not all) of the "classic" dinosaurs in Aves, and
> Patterson once suggested using a definition for Aves which was the same as
> Gauthier's formulation of Pseudosuchia (i.e., modern birds and all taxa
> closer to modern birds than to crocodilians).  However, the majority of
> working paleontologists and other interested folks are content with
> restricting Aves to some subset within maniraptoran coelurosaurian dinosaurs.
>
> _Diatryma_, _Foro_, _Dinornis_: now those are some critters everyone would
> agree are extinct avians.
>
> >and others love to refer to them as
> >non-avian dinosaurs.
>
> Oh, yeah, we "love" to.  Just as I "love" when I refer to non-human
> primates.  It has nothing to do with trying to be precise, I guess...
>
> >I guess that makes us non-extinct pelycosaurs.
>
> No, but we are extant synapsids.
>
> >Even if
> >we agree to confine our discussions to pre-KT creatures, I wonder how many of
> >us would stick around if the focus was extensive rambles on prehistoric
> >pigeons and sparrows.
>
> (Hey, a pigeon or sparrow prior to the K-T boundary (which would be
> different from a "pre-KT", or Jurassic and earlier, taxon... sorry, more
> nits to pick...) would be a MAJOR discovery!!).
>
> Focus on Mesozoic birds?  Not exclusively (I like my theropods with stumpy
> two-fingered arms!), but they certainly fall within the bounds of the reason
> this list was established (i.e., discussion of dinosaur science).
>
> Thomas R. Holtz, Jr.
> Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
> Dept. of Geology              Email:tholtz@geol.umd.edu
> University of Maryland        Phone:301-405-4084
> College Park, MD  20742       Fax:  301-314-9661