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Re: Ostrom in Colorado
If you don't want to hear about Archeopteryx and birds, delete
this right now!
Just to comment a bit further on John Ostrom's visit to
Colorado...as Abbott said here, Ostrom has casts of all 7
Archies at Yale, and I think that's the only place that does.
I also saw the lecture on the School of Mines campus last
Thursday afternoon. It was mostly about osteology, and the
evolution of the muscle/tendon (supracoracoideal) that goes
through the intraossial canal. That muscle attaches to the top
of the humerus, and it is for supinating the wing during the
recovery stroke of flight. Archie didn't have this, but even in
modern birds, you can sever the attachment, and the bird can
I saw the "lunate carpal" that we've talked about in this group.
It's sort of a three-dimensional phenomenon, which might be why
it's hard to see in some orientations. In the highly developed
state in more modern birds, it looks a lot like a one-sided
artiodactyl tarsus--a deep groove with one high process
(represented by the lunate bone in Archie) defining it. Unlike
in artios, the groove is at an angle, maybe to facilitate the
rotation of the wing in the flight stroke, or during other
activities (as Lipps and Cowan have suggested, fighting and
display...and as I looked at the diagrams and fossils and
drawings--I began to believe.)
He did show the "insect trapping" diagram again, that shows
Archie grabbing or knocking insects out of the air with the
And the stuff about the long legs meaning cursorial (roadrunner,
secretary bird)--what about quail, which are cursorial but have
pretty short legs, and wading birds, which aren't exactly
cursorial but have long legs...oh well.
I also got to walk Dinosaur Ridge (Jurassic bones and tracks,
Cretaceous tracks) with Dr. Ostrom, Martin Lockley, Adrian Hunt,
Bob Weimer (not dinos, but stratigraphy) and a number of other
fairly well known folk on Saturday (be still my beating
He says Archie #7 has an ossified sternum, but is also smaller
than all the other Archies. So, it might imply some things about
size and age, but only if you think the sternums from the other
6 Archies are missing because they were cartilaginous.
He says he'll be looking for fused vertebrae in Confuciornis
when he gets a chance. He expressed some doubt about the age on
the Chinese specimens, based on the fact that there's been
considerable controversy about the dating of the rocks even
before the discovery of the fossils--that there's a possibility
they may not be much (any?) younger than say, Hesperornis.
Colorado School of Mines