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RE: 11th specimen of Archaeopteryx
> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu]
> On Oct 27, 2011, at 3:42 AM, Tim Williams wrote:
> > Yes, there are several lines of evidence that _Archaeopteryx_ was
> > incapable of sustained, flapping flight. _Confuciusornis_ too; and
> > probably _Sapeornis_ as well. If this is true (and I'm sure not
> > everyone agrees!) all basal birds might have been gliders.
> > Nevertheless, it is possible that these gliders might have
> used simple
> > flapping motions in order to gain height or added forward momentum
> > during the glide.
> This is certainly not impossible, but it should be noted that
> any model suggesting a "limited flapping" precursor needs to
> consider the potential for appropriately manipulating
> vorticity on the wing (and, in this case, rapidly increasing
> circulation and abruptly reducing it - otherwise, the animal
> loses more than it gains). I have yet to see this even
> whispered in the literature with regards to early birds,
> which is pretty concerning.
I wonder to what degree "controlled flapping descent" may have a role here?
Thomas R. Holtz, Jr.
Email: firstname.lastname@example.org Phone: 301-405-4084
Office: Centreville 1216
Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
Faculty Director, Science & Global Change Program, College Park Scholars
Mailing Address: Thomas R. Holtz, Jr.
Department of Geology
Building 237, Room 1117
University of Maryland
College Park, MD 20742 USA