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Ostrom symposium notes
Fun symposium indeed; so much going on behind the scenes as well as
on the floor. And a fabulous party at the Peabody Friday night, what a
bash! Ouch, my aching head... Anyhoo, a few quick comments:
Ron Orenstein writes:
"One interesting historical footnote from the floor: Thomas Huxley was not
the first to suggest a link between dinosaurs and birds. Huxley apparently
cited the work of a German embryologist named Gegenbauer (?), who suggested
the connection after his study of chick embryos, which he saw as quite
dinosaur-like. Does anyone out there know more about this?"
A very nice review is in Larry Witmer's 1991 paper on the history of the
bird origin debate, IIRC. Don't have the precise ref but it's in the H.-P.
Schultze and L. Trueb (Eds.) Origins of the Major Groups of Tetrapods book.
"Peter Dodson raised the issue of Protoavis; Sereno replied that
he considered it a composite, but added that its braincase is that of a
By my memory it was Peter Galton who asked and Mark Norell who replied, but
I could be wrong. I've seen Protoavis recently and it does need to be
addressed in detail, but who's gonna take the time (and ruffle some
"In a provocative question, the moderator asked Phil Currie, Larry Martin
and Louis Chiappe what it would take to convince them that their theories
of bird origins were wrong. Currie replied (and Chiappe agreed) that it
would take the discovery of material showing a genuinely viable
alternative. [yep, that's the answer I wanted from them, they win a new car!]
Larry Martin plumped for a clearer character analysis,
remarking that elongate penultimate digits, for example, are widespread in
tetrapods and that anterorbital subsidiary fenestrae also occur in some
It is worth noting here that, amid some ramblings, he did say that an
unequivocal feathered dinosaur would cause him to rethink his ideas. Which
is the other answer I wanted to hear.
Philip Bigelow writes (quoting Ron first):
" > He <Phil Currie> showed slides indicating that
> these structures appear thicker at the base, with longer and thinner
> extending further out, a condition that also seems to prevail in
> Protarchaeopteryx. Currie interprets this as representing a thick
> breaking up into a distal plumulaceous portion, indicating a simple
> branching structure - though I am not sure I saw this in the slides.
We need SEMs!"
These are apparently being done along with other methods of analysis,
including looking for Paul Davis/Derek Briggs's feather-specific bacteria
On a few other issues that came up, or should have come up:
1) The Archaeopteryx pubis orientation controversy must die. Please. As
with many other specifics of its anatomy, you ultimately have to trust your
or another researcher's opinion, that's what it comes down to. Although
another specimen might clear things up a bit, couldn't it...?
2) Please stop citing Rayner's earlier work as "proving" that a ground-up
origin of flight is "biophysically impossible". He (and many others)
clearly doesn't agree with it now.
3) As Rayner noted, the ground up vs. arboreal dichotomy should die, too.
Or at least be put on hiatus pending more real data. Let's move on to more
interesting and testable questions.
4) Man oh man do we need those basal alvarezsaurids. I guess that has
already become a cliche, and their relationships with other
maniraptoriforms will remain unclear until we do find some earlier forms.
John R. Hutchinson
Department of Integrative Biology
3060 Valley Life Sciences Bldg.
University of California - Berkeley
Berkeley, CA 94720 - 3140
Phone: (510) 643-2109
Fax: (510) 642-1822