Re: WING FEATHER ATTACHMENT

["Tim Williams" <twilliams_alpha@hotmail.com>]

David Marjanovic wrote:

> Just like in living birds -- number 2 and only number 2, which was the
> longest and most robust one. The thumb and number 3 were free and probably
> able to grasp below the wing (best seen in *Confuciusornis*, less obvious 
> in
> *Archaeopteryx*.) Regardless of whatever you mean by "raptor"... :-)
> Oh, and while you are at it, don't put wing feathers on the upper arms.

Do you mean "Don't put flight feathers on the upper arms" or "Don't put 
*any* feathers on the upper arms"?

This is an important distinction for both restoring _Archaeopteryx_ and for 
adaptive scenarios for the evolution of flight within theropods.  No known 
specimen of _Archaeopteryx_ preserve tertials (the remiges attached to the 
humerus) though in at least two specimens (Berlin and London) the primaries 
and secondaries are clearly present.

Then again, no _Archaeopteryx_ specimen shows contour feathers on the body 
either.  A 19th century sketch of the Berlin specimen does show hair-like 
feathers associated the body (perhaps this is what Greg Paul is referring to 
in _PDW_).  These feathery structures are not now evident on the actual 
specimen, either because they were polished away or because they never 
existed in the first place.

Was there a gap in _Archaeopteryx's wing between the elbow and the body 
wall?  Maybe not.  It is possible that _Archaeopteryx_'s inner wing was 
filled in with a more simplified, primitive type of feather between the most 
proximal secondaries and the body wall.  These feathers (unlike the more 
distal remiges - the primaries and secondaries) were not preserved, just as 
the contour feathers on the body were not preserved.

Just a thought.  Opposing opinions are welcome.


Tim





------------------------------------------------------------

Timothy J. Williams

USDA/ARS Researcher
Agronomy Hall
Iowa State University
Ames IA 50014

Phone: 515 294 9233
Fax:   515 294 3163



_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp