Re: Feathered Dragons: Studies on the Transition from Dinosaurs to Birds

[Jeff Hecht <jeff@jeffhecht.com>]

At 12:53 AM -0700 4/26/04, Mickey Mortimer wrote:
> Hopp and Orsen, 2004. Dinosaur brooding behavior and the origin of flight
> feathers. 234-250.
> A nice rationale behind elongating remiges, asymmetrical remiges and the
> folding wing.  I think WAIR explains elongating remiges and the flight
> stroke better though.  And why do neoflightless brooding taxa have
> symmetrical remiges if asymmetrical ones are still so useful for brooding?
> Also doesn't explain the retrices, which seem to evolve around the same time
> as remiges.

Isn't it likely that a lot of small advantages of larger wings added 
together to give the evolutionary push needed to increase their size? 
Add the marginal advantage in wing-assisted running up inclines, the 
marginal benefits of larger wing area in gliding or jumping, and the 
marginal benefits in brooding, and you get a stronger trend. I'm wary 
of any single simple explanation for the transition from forearms to 
wings.  -- Jeff Hecht