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Re: Feathers as fossilized behaviour (was:Re: Function Talks at Ostrom Symposium)

I wrote:

<<Okay, oviraptors may not have had feathers to preen, yet they (or at
least two, *Ingenia* and *Conchoraptor*) have denticulate margins to
their premaxillae; who knows what shape the rhamphothecae (if any) may
have taken on _top_ of those margins.>>


<...again, this was a sort of throwaway speculation at the end of my
post. I gather you buy the main points?>

  Yes, that both dromaeosaurids may have reduced their brachial
feathers in response to bloody feeding practices and that
*Caudipteryx* may have used its long, slender teeth to comb and
"arrange" its feathers, putting all in order. 

Betty Cunningham wrote:

<<...since all birds preen feathers and all birds lack teeth, I don't
see how anyone could imply that lack of teeth meant lack of preening
ability and thus no feathers.>>

  He's not implying this, as he may say, but that *Caudipteryx* may
have exapted teeth to comb with, only that. Many (maybe even all)
diving birds arrange their pelage with their jaws. Some have adapted
other parts of their bodies to perform the task, such as the galliform
(just an example, not excluding other groups) comb claw of the second
pedal digit, yet even these still use their beaks to preen (I actually
refer specifically to chickens and turkeys).

and Dinogeorge wrote:

<Conversely, it's therefore also difficult to see why anyone might
suggest preening as a function for teeth.>

  Why not use the teeth? No, this isn't a vacuous answer. The arms
were short and probably insuitable for grooming, even though the claws
were each hetero-"ungulate" (new term, suggests differentiation in
claws of the same limb); and while the legs were particularly long, it
would be awkward for the animal to have to sit or put itself in some
uncomfortable position just to rearrange it's arm feathers; the head
is the next best thing, perhaps _the_ best thing considering modern
avians, and it just happens to retain teeth, perhaps for dietary
reasons. Why not use the teeth? They're perfectly shaped for such a
job, though I would think serrations would be better, but sometimes
you gotta make due with what you got. It _could_ use the denticulate
margin of the premaxilla posterior to the teeth, but who knows: future
finds may clarify the issue, and I know some of you are tired of
hearing this old saw.

  However, I think Ron'd quite astute.


  On a slightly separate note, even noting the nature of the plastic
enclosures, what anybody able to take close photos or good detail
drawings of the manus and pes and are willing to share them with me?
These are of particular interest to me, as I have also illustrated the
skeleton (on my site, under _Caudipteryx_) and I just want to make
sure I got anything correct.

- Often, it is the man who is brought
  down the path to the end who does
  not see his own steps. -

Jaime A. Headden

Qilong, the website, at:
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