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At 11:57 AM 10/16/96 -0500, Daniel Lipkowitz wrote:

>On the subject of propatagia, which I hope I am correctly
>identifying as the web of skin which you placed on the arms of the
>various maniraptors in the book, I recently saw a life-size model
>Deinonychus in a shop in New York which possessed this feature.

        I am afraid that I must return to the horrible bird-origins thread
for moment to propose that, if you accept the current proponderance of
evidence that birds are the sister to dromaeosaurs, there is one interesting
side-effect to the propatageum proposal.
        DANGER:  Speculation...
        I think the possibility and problem of the propatagium is directly
linked to the old "birds started as gliders with patagia" theory.  Several
people, expert and novice alike, have argued here and elsewhere that this
theory is untenable for various reasons.  If it is untenable (I said "if"),
and birds started with feathered wings and not patagia, it is *possible*
(note, I do not say "necessary") that dromaeosaurs, if they required a
propatagium, would have developed feathered arms instead, or retained them
from a "protobird" ancestor.  Certainly, I believe it is easy to see where
these two problems (flight and the reasons cited for a patagium on
dromaeosaurs) might find a similar solution either way.
        In fact, the argument for propatagia which was put forth sounds a
lot like the scenarios Dr. Norton and I proposed for the development of flight.


>-undergraduate senior in search of a Ph.D.-
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| Jonathan R. Wagner                    "You can clade if you want to,     |
| Department of Geosciences              You can leave your friends behind |
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