Re: 11th specimen of Archaeopteryx

["Habib, Michael" <MHabib@Chatham.edu>]

On Oct 27, 2011, at 3:42 AM, Tim Williams wrote:
> Yes, there are several lines of evidence that _Archaeopteryx_ was
> incapable of sustained, flapping flight.  _Confuciusornis_ too; and
> probably _Sapeornis_ as well.  If this is true (and I'm sure not
> everyone agrees!) all basal birds might have been gliders.
> Nevertheless, it is possible that these gliders might have used simple
> flapping motions in order to gain height or added forward momentum
> during the glide.

This is certainly not impossible, but it should be noted that any model 
suggesting a "limited flapping" precursor needs to consider the potential for 
appropriately manipulating vorticity on the wing (and, in this case, rapidly 
increasing circulation and abruptly reducing it - otherwise, the animal loses 
more than it gains).  I have yet to see this even whispered in the literature 
with regards to early birds, which is pretty concerning.

Cheers,

--Mike H.


Michael Habib
Assistant Professor of Biology
Chatham University
Woodland Road, Pittsburgh PA  15232
Buhl Hall, Room 226A
mhabib@chatham.edu
(443) 280-0181