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Re: CNN: how first birds flew



This quote from the Nature (at:
http://helix.nature.com/nsu/990506/990506-3.html )article by Henry Gee:

Some of Archie`s relatives..." seem to have been able to have moved their
forelimbs in a flapping fashion. "

I was under the impression that Maniraptoriformes (at least) were restricted
in the motion of their forearms to this "flapping type" of motion in a
single plane. Is this not true? What about theropods in general, wasn`t  the
arm motions of all similarly restricted? How was it in T_Rex?


Theropods may have been fast enough for takeoff flight from the ground, but
there are other factors involved. Flight feathers (for one), which to me are
extremely specialized structures, and flapping motion, which if restricted
to such would seem to be an unlikely "pre-adaptation" to have developed for
the future use in flying. These two items alone seem better explained as
holdovers from a previously specialized function of actual flight rather
than being of significant use to a non-flight -capable organism in it`s
forays on the ground.