Re: Flight capablities of Archie & Confucius? Not so good...

[MKIRKALDY@aol.com]

Gareth Dyke has a guest post regarding the paper on Dave Hone's blog  at:
 
http://archosaurmusings.wordpress.com/2010/05/14/guest-post/#more-3517
 
Mary
______

In a message dated 5/13/2010 4:35:06 P.M. Eastern Daylight Time,  
tholtz@umd.edu writes:
Another paper out (following Senter's 2006 APP paper  looking at shoulder
morphology) suggesting that Archaeopteryx and  Confuciusornis were not
powered fliers:

Nudds, R.L. & G.J. Dyke.  2010. Narrow Primary Feather Rachises in
Confuciusornis and Archaeopteryx  Suggest Poor Flight Ability. Science
328:887-889. [DOI:  10.1126/science.1188895]

The fossil birds Archaeopteryx and  Confuciusornis had feathered wings
resembling those of living birds, but  their flight capabilities remain
uncertain. Analysis of the rachises of their  primary feathers shows that 
the
rachises were much thinner and weaker than  those of modern birds, and thus
the birds were not capable of flight. Only if  the primary feather rachises
were solid in cross-section (the strongest  structural configuration), and
not hollow as in living birds, would flight  have been possible. Hence, if
Archaeopteryx  and Confuciusornis were  flapping flyers, they must have had 
a
feather structure that was  fundamentally different from that of living
birds. Alternatively, if they  were only gliders, then the flapping wing
stroke must have appeared after the  divergence of Confuciusornis, likely
within the enantiornithine or  ornithurine radiations.
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