Re: Archaeopteryx flight

[Patrick Norton <ptnorton@suscom-maine.net>]

Jon Barber wrote (in part):

> D) It lacked an alula, which assists in low-speed flight and 
> maneuverability control.<

It's been my hypothesis for a long time that the aerodynamic function of the 
alula could have been fulfilled by the exposed finger claws of early birds 
such as Archie (see my post from several years ago at 
http://dml.cmnh.org/2001Jan/msg00543.html).  As I note in that post, other 
vertebrate flyers without feathers (bats and pterosaurs) have/had 
non-feathered leading edge protuberances (aka, claws) in approximately the 
same leading edge location. It's my belief that these did/do function like 
an alula.  This could be tested empirically, but I haven't done it, and 
neither has anyone else that I know of. Without testing this, it's premature 
to dismiss low-speed flight and maneuverability control simply because this 
protuberance wasn't comprised of feathers.

PTN