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RE: Bird necks



Hi
There is a thesis on bird necks that might be useful: 'Evolutionary
morphology of the neck in anseriformes; neck movement as an adaptation to
the aquatic environment' by A. van der Leeuw. I don't know if it is
available in pdf format though...

Hanneke

Hanneke J.M. Meijer
Institute for Fundamental and Clinical Human Movement Sciences 
Vrije Universiteit, Amsterdam, The Netherlands
email: h.meijer@fbw.vu.nl
tel: (031) (0)20 5988252
fax: (031) (0)20 5988529


-----Original Message-----
From: Mickey Mortimer [mailto:Mickey_Mortimer111@msn.com] 
Sent: Tuesday, March 29, 2005 10:54 PM
To: dinosaur@usc.edu
Subject: Re: Bird necks

Daniel Bensen wrote-

> Looking at skeletons of ancient birds (not so much Archaeopteryx as things
> like Confuciusornis and Cathayornis) I am continuously surprised by their
> short little necks.  Cathaynoris has a short curve of cervical vertebrae
> (4-5 looking at the photo), which Confuciusornis's neck is even shorter.
> Does anyone have any theories as to why these necks are so short?  They
make
> sense aerodynamically, I suppose, but when the birds were at rest, they
must
> have had a hell of a time looking around.

They weren't short.  It's just that the posterior cervicals don't always
preserve so well.  Here's are some cervical counts of ornithurines (sensu
Gauthier)-
Spanish nestling 9 (Sanz et al., 1997)
Liaoxiornis 10 (Chiappe, 2002; contra Hou and Chen, 1999)
GMV-2158 10 (Chiappe, 2002)
GMV-2159 10 (Chiappe, 2002)
Eoenantiornis 11 (Hou et al., 1999)
Aberratiodentus 11 (Gong et al., 2004)
Patagopteryx 13+? (Chiappe, 1996)
Yixianornis 12 (Clarke et al., 2002)
Apsaravis 12 (Clarke and Norell, 2002)
Ambiortus ~14 (Kurochkin, 1999)
Confuciusornis has at least eight (Chiappe et al., 1999), though only five
are preserved in the Cathayornis holotype (=Sinornis).  But they probably
had ten to eleven in total.

Mickey Mortimer
Undergraduate, Earth and Space Sciences
University of Washington
The Theropod Database - http://students.washington.edu/eoraptor/Home.html