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Florida



I guess I'll throw my 2 cents into the various thoughts that
have come out of the meeting.

As far as great talks, I particularly enjoyed Larry
Witmer's talk on various types of inferences from I to III
and some of his new reconstructions. It was, as is usual for
Larry, a nice and concise discussion of exactly how we can
say what we say and with what confidence. Type I inferences
are fully supported by phylogenetic data using phylogenetic
bracketing. Feathers in  Eocene birds is a safe one.
Accepted unless the evidence suggests otherwise. This is why
the position of Caudipteryx is so important in many of
today's discussions. On the other end of the spectrum, Type
III inferences have no phylogenetic support (from before or
after) and need a strong case be made for acceptance using
morphology or other lines of evidence. I'll wait for Larry
to publish to outline the examples he gave - all very
convincing and, at times, quite decimating to current
reproductions.

Postosuchus urinating on WWD would be a type III that could
still be strongly implied with good solid evidence for it,
which, of course, there is not at this time. Jack Horner at
SVP a couple of years ago stated that Pachy head-banging was
also a type III inference (which it is) and  implied that,
as a consequence, it  was a long-shot to be supported. I beg
to differ (on the available support, not the type III
inference part) and am finally getting back to building the
large rebuttal. We must remember that herbivory in dinosaurs
also is a type III inference and I suspect few would argue
against the presence of some herbivory in dinosaurs

All-in-all a great talk - as was Gatesy's talk. A real
class act and great stuff on bird flying. Hope to really
combine some of his, Kent's and our approaches on a whole
list of things over the next couple of years - throw in Rolf
Johnson, Don Henderson, Weishampel and Dave Norman  and I
think we'll have some exciting times. Got to play golf on
Monday with Art Andersen, Steve and his Dad - who lives
there sometimes - and, of couse, his dad killed us all.
Steve, Art & I hit the ball a mile a few times, sometimes
even in the fairway!

I also had a warm part in my heart for Sankar's talk. I
have to confess I have always assumed flight happened along
that line from an at least partially arboreal dinosaur,
which I consider small theropods to be preadapted for as
well as flying in general, and Sankar took a very sane
approach to the problem. I don't know if I at all agree with
the exact taxa he would infer are at the various stages, but
his talk was very enjoyable and important food for thought.
As always, missed lots of talks due to talking in the halls.
As you get older, you seem to talk in the halls more and
more.

Finally (for this note, not for good talks), Kevin Padian
gave a nice, rational talk on the vacuousness of the
anti-dino bird origin arguments and pressing people to do
what was possible to finish getting Bambi permanently into
the Graves. It was very nice.

As to the debates, I actually found them disappointing and
found the anti-dino group's arguments to be old and, at
times, way off the scale for believability. I was hoing for
stuff that would throw us into a real tizzy on this matter
but it did not happen. I would greatly enjoy having real
contrary evidence on this  to stir stuff up. I was doomed to
be disappointed here, however.

Thankfully, John Ruben did not reassert his previous
suggestion that the apparent pubic foot in Archie is just a
hyperpubic cup that had been folded over onto itself to look
like a foot. A very strange suggestion of big distortion in
Solnhofen stuff. His current line really came across as, I
don't believe things when they look exactly like I think
they shouldn't, and I happily ignore evidence of
transposition of elements when it meets my expectations. A
VERY disappointing talk, frankly, which I think, along with
his very unbelievable stuff on Sinosauropteryx and Skippy
innards and their implications for breathing mechanisms,
pretty much took him out of the debate as a strong player.

Larry Martin based much of his talk on his model of Archie
and made arguments from it. Of course, without the model to
play with, it is tough to see this as more than an analysis
of the ancestor possibilities of Larry's model. Feduccia's
talk was incredibly disappointing both for its bluster and
his apparent purposeful obfuscation of the evidence. He
seems to think that ground-up and trees-down discussions
currently have a strong effect on the phylogenetic
arguments. They do not - they are independent discussions. I
fully see (until an amazing series of fossils moves the
reconstructions elsewhere, which could happen) dinos as bird
ancestors but think, as I mention above, the most likely
route is top down. His discussion of pterosaurs was totally
irrelevant and it was a surprise to Jim Clark the other day
when I told him that Feduccia used his work as anti-dino
evidence when, in fact, it only suggested that pterosaurs
were not running marathons on the ground. As far as we all
know, it has not changed the phylogenetic position of
pterosaurs one bit. The developmental stuff is obviously the
most interesting but Jacques has dismembered it already and
it was a surprise to hear Feduccia actually mention during
the discussion that the there were contra arguments that had
a little merit. He didn't mention that during his talk and,
frankly, to be scientific you should at least discuss the
strong points of the opposition. He relies on this one
character to be a keystone character that outweighs all
others and, frankly, if we have learned nothing else over
the past 50 years and with recent developmental work, it's
that we fail badly whenever we opt to accept a single
character as that overbearing. About Feduccia's talk -
REJECTED!

Frankly, for the arguments they were making against
bird-origins in the dinosaurs there are well established
mechanisms for testing various alternatives quantitatively -
including Larry Martin's suggestion that we all test for
Greg's secondarily flightless bird origin of some theropods
idea - but Neither Alan or Larry or John or Storrs seems to
want to be bothered. Shame, there is lots of leeway
available to recoding and even experimenting with
character-weighting that might shed neat light on the
subject. Many of us are not blindly accepting of parsimony
as the only criterion for acceptance of hypotheses and
commonly people discuss how various reasonable hypotheses
imply varying tree lengths. I also suspect if Larry were to
code things his way and do as I mention, they could
strengthen their argument. Not enough, I think, but I would
like to see it. However, it would require explicit
statements that could be discussed in detail and that seems
to be where the anti-dinos people don't like to tred.

So, the discussions were less stimulating for me because I
was greatly disappointed in the strength of the anti-dino
groups arguments. I hope someone will do a better job as a
contra argument than they have because I could enjoy a lot
more fuzziness on this issue but you gotta go where the
evidence points you for now, which is in the dinos.

Anyway, the Graves people were uniformly very nice. Enjoyed
all the activities and enjoyed seeing the crocs. Figured the
alligator wrestler didn't know he was in front of
paleontologists who seemed to be rooting for the alligator,
though the crocs really didn't seem particularly worse for
the effort, although the wrestler got cracked in the leg
once with a tail that must have smarted some and the good
chief lost a finger a month ago. All the people at Chief
Billies, including the wrestler, were very nice as well and
it was a great field trip overall with plenty of crocs
apparent out the window of the bus on the way there. I
suggest evryone go if they find their way down there.

Just some thoughts.

Ralph Chapman

Ralph E. Chapman
Applied Morphometrics Laboratory
National Museum of Natural history
ADP, EG-15  NHB, 10th & Constitution, NW
Smithsonian Institution
Washington, DC 20560-0136
(202) 786-2293, Fax: (202) 357-4122
Chapman.Ralph@nmnh.si.edu