Re: A New Hypothesis for the Origin of Flight?

[Waylon Rowley <whte_rbt_obj@yahoo.com>]

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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