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Re: _Caudipteryx_ feathers (was secondary flightlessness)



I wrote:

<<These primaries are, actually, very similar to the arm feathers of
the emu (*Dromaius*) which are tapered down to a point (at least for
those first primaries) and are symmetrically "vaned". The barbs of the
feathers do not seem to interlock, so this is a minus for
*Caudipteryx* being a sustained-leaper.>>

Ralph Chapman III wrote:

<Regarding the pronounced double flexion of the remiges you observe in
the _Caudipteryx_ specimen, is it possible that this flexion you see
occurred after death?  Could not the rachises have been subjected to
unusual traumas postmortem?>

  Ah. I had not considered this. The specimen in question, the
holotype, seems to have suffered what I assume to be post mortem
scavenging, where the extremities are intact but the juicy bits (the
innards) have been scattered about, and given the prescence of turtles
in the formation, would it be possible that the animal (but apparently
not the paratype) was scavenged after it fell (or whatever) into the
water?

  Now, saving face, I offer a theory to cover my rear.
  
<Regarding interlocking barbs, at the National Geographic Society
press conference on Tuesday, June 23, 1998, Dr. Philip J. Currie said
of the _Caudipteryx_ feathers that "barbules must have been present"
to hold the barbs parallel (as they appear in the specimens).  The
rachises of adjacent remiges likewise appear to have been preserved
parallel to one another in the photographs, as well as in the
accompanying illustrations.>

  In my haste, I got confused. I mixed *Protarchaeopteryx* up with
*Caudipteryx*, and in fact made a double error, confusing either with
the lack of evidence concerning "emu feathers" [see below].

<Given the lack of resolution in the fossil feathers (in so far as the
photographs reveal them), I fail to see the basis for applying emu
feathers as an appropriate analog to the preserved feathers of
_Caudipteryx_.>

  I used the emu's feathers for their superficial resemblance, but
ostrich feathers, which have barbules (I believe) may be the better
analogy? For the sake of it, I seemed to have carried the emu analogy
a bit far.

  Appologies for my jump in logic.

  Jaime A. Headden
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