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Re: Archaeopteryx flight



I would expect extended digits to perform about as well as an alula, but at a somewhat greater weight penalty.

As an aside, how often are alulas shed, and are they shed at any particular point in the moult?

JimC

----- Original Message ----- From: "Jon Barber" <augray@sympatico.ca>
To: "Dinosaur Mailing List" <dinosaur@usc.edu>
Sent: Sunday, October 23, 2005 8:43 PM
Subject: Re: Archaeopteryx flight



At 05:49 PM 10/20/2005 -0400, Patrick Norton wrote:
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>
While the first digit may have functioned similarly to an alula, I suspect that it did a relatively poor job. The recent paper that describes Eoenantiornis points to the parallel evolutionary refinement of the alula in both the Enantiornithes and the Euornithes.