[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Senter 2006, Confuciusornis, and humeral mobility

Scott brought up the KU Microraptor study. Of course I was one of the authors 
who wrote the reply to that paper, but I've never written anything in public 
about it before.

I will write two things here.

1) I would have liked to see the KU team test Dr. Xu's configuration for 
gliding ability. The team knew Dr. Xu's configuration because they saw it when 
they participated in the NOVA episode "The Four Winged Dinosaur". I was on Dr. 
Xu's team and we found that his configuration did the best in wind tunnel 
tests. By failing to test their splayed configuration against Dr. Xus 
parasagittal configuration they failed to test their hypothesis against its 
main alternative.

2) The pelvis that they have is the exact same one that I examined, and that is 
depicted in the NOVA episode. It is as flat as a burnt cookie and completely 
distorted. The pelvis published in Burnham's dissertation has not been prepared 
any further than what I saw, and CT scans cannot by themselves correct the 
distortion in this fossil.

On Mar 23, 2011, at 1:04 PM, Scott Hartman wrote:

> On Wed, Mar 23, 2011 at 11:59 AM, Jason Brougham <jaseb@amnh.org> wrote:
>> Confuciusornis should have had extremely low scapular mobility. The 
>> coracoids and scapulae are fused (Chiappe et al. 1999) and the coracoids 
>> attach to the sternum at a wide facet.<
> Quite so.  Pretty much without exception pectoral girdle mobility is
> sacrificed progressively at the level of Maniraptora on up to Aves.
> Reduction in overall dorsal flexibility (which of course is in part
> tied to pectoral girdle mobility) with concurrent increases of
> mobility in the cervical series follow the same pattern.
> Maniraptorans are the anti-squirrels.
> -Scott
> -- 
> Scott Hartman
> Scientific Advisor/Technical Illustrator
> (307) 921-9750
> www.skeletaldrawing.com

Jason Brougham
Senior Principal Preparator
American Museum of Natural History
(212) 496 3544