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RE: Ornithomimus had feathers and "display" winglike forelimbs

  Note the use of "ornithomimids" in Greg's message, "ornithomimosaurs" in 
Zelenitzy's and Williams'. There is a distinction:

  Basal ornithomimosaurs (e.g., *Harpymimus okladnikovi*) has large, more 
block-like distal carpals, while more derived forms [or "ornithomimids"] have 
flatter, less "mobile" distal carpals. This should influence mobility to some 
degree, and implies that the wrist was more mobile in some taxa than in others.

  But that's not all: Greg is only talking about the wrist, but arm mobility 
and flexural capability occurs at three different points in the arm: shoulder, 
elbow and wrist. Elbow mobility has never been considered impeded, and the 
shoulder should have a fairly large range of flexion-extension to it; if 
anything, the "brooding" option or disply _does not require a folding 
mechanism_, and indeed that was a large point of the Hopp/Orsen papers on the 
subject. In these cases, folding becomes selected for when a feature is being 
developed, such as large feathers on the arm + folding following small feathers 
+ no folding. In Cstonyi's art done for the paper, note that the ornithomimids 
show minimal wrist flexion, while the shoulder and elbow are strongly flexed. 
Someone did their research.


  Jaime A. Headden
  The Bite Stuff (site v2)

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

"Ever since man first left his cave and met a stranger with a
different language and a new way of looking at things, the human race
has had a dream: to kill him, so we don't have to learn his language or
his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 

> Date: Fri, 26 Oct 2012 11:17:11 -0400
> From: GSP1954@aol.com
> To: dinosaur@usc.edu
> Subject: Re: Ornithomimus had feathers and "display" winglike forelimbs
> But ornithomimids did not have folding arms so they were not critical for
> protecting such irregular feathers. Folding arms are more selective for
> protecting finely defined wing airfoils.
> And it is not known whether theropods as basal as or more basal than
> ornithomimids brooded their eggs.
> GSPaul
> In a message dated 10/26/12 12:09:41 AM, tijawi@gmail.com writes:
> << The presence of long forelimb feathers might also explain the
> appearance of the semilunate carpal wrist (which appears to have
> evolved *after* ornithomimosaurs): It was simply to help fold the
> forelimbs, and get the pennibrachia out of the way when they weren't
> in active use. No need for a flight-related explanation, or a
> predation-related one. >>
> </HTML>