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Re: Sifaka and Chukar Behavior: Trees Down or Ground Up?



David Marjanovic (david.marjanovic@gmx.at) wrote:

<I don't, and neither does Dial in the Ostrom Symposium volume. The finger
claws are perpendicular to the plane of the wing, and only the 2nd finger
is involved in the wing at all.>

  This was done prior to the discovery of NGMC 91, "Dave" as well as
expansive integument in *Cryptovolans* and *Microraptor*, which show a
tuft of alula-like feathers in the first digit, and the overlaying of the
second digit rachis on the third metacarpal and digit. The advanced
structure in early birds shows that, at least theoretically, that the
third metacarpal and third digit were advancing at a similar rate and time
in feather-winged theropods to aerodynamic constrainsts and pressures.
Dial is out of diate slightly on that issue.
 
<I forgot who wrote that Solnhofen doesn't preserve any flying dinosaurs
except *Archaeopteryx*... there is the isolated feather which is more
asymmetrical than any known feather of *Archaeopteryx*. More like the foot
feathers of *M. gui* :-) or the primaries of a recent flying bird.>

  You'd have to prove that the feather could not pertain to
*Archaeopteryx*; similarly, others have differentiated several distinct
species from the complex of birds, so the idea of *Archaeopteryx* as the
only bird my be wrong on another level, even though the conceivers of the
sole-bird idea considered all fossils a single or at least two species.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

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