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Re: A New Hypothesis for the Origin of Flight?
David Marjanovic wrote:
> Aren't feathers supposed to be lighter than tail
> vertebrae? (Or is that one
> of those truisms?)
Oh yes, of course. I suppose they would have to be
longer in order to generate enough torque to keep the
body perfectly balanced.
> Maybe just to make it stiffer -- few long instead of
> many short vertebrae
> means fewer joints in the tail.
Different ways of doing the same thing. What do you
know about the new long-tailed "deinonychosaur" from
the Jehol? Does it have retrices like Archie, and if
so, is there a distal fan?
> Thanks for the explanation... the above would be a
> good reason to evolve a reverted hallux very early.
> Instead, it comes very late.
Or is lost early on in forms that returned to the
ground. In DA, HP Gregory Paul suggested that in quite
a few specimens we are unsure of the placement and
condition of the hallux, due to disarticulation.
> Hardly enough to make a living when there are few or
> no angiosperms around.
Oops, my bad. Diet really isn't that important. The
pressure to move out further on branches may just be
to switch trees.
Cheers,
Waylon Rowley
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