Re: pteros have lift-off

[dinoboygraphics@aol.com]

> > > Greg Paul in dinos of the air suggested that Archaeopteryx and other 
birdy
descendants of short-armed theropods gained their long arms from 
tree-clinging
and tree-climbing. Is this the general consensus?<<<

No.

While it's fair to say that Greg's ecomorph is one of the competing 
hypotheses for reconstructing the selective environment that lead to 
proto-avian flight, it's hardly the only one, and not the one that 
several workers (including myself) favor.

Scott Hartman
Science Director
Wyoming Dinosaur Center
110 Carter Ranch Rd.
Thermopolis, WY 82443
(800) 455-3466 ext. 230
Cell: (307) 921-8333

www.skeletaldrawing.com

-----Original Message-----
From: David Peters <davidpeters@att.net>
To: Michael Habib <mhabib5@jhmi.edu>
Cc: Mike Habib <habib@jhmi.edu>; jrccea@bellsouth.net; dinosaur@usc.edu
Sent: Sun, 18 Jan 2009 5:59 pm
Subject: Re: pteros have lift-off






Greg Paul in dinos of the air suggested that Archaeopteryx and other 
birdy
descendants of short-armed theropods gained their long arms from 
tree-clinging
and tree-climbing. Is this the general consensus?

Can the same be said of pterosaurs? Or did terrestrial take-off somehow
encourage longer antebrachia?

Also, did basal short-metacarpal pterosaurs create a Z-fold in the 
forelimb?

And finally, what was that maximum carpal angle? and did it fold 
medially,
laterally, or posteriorly?

PS thoughts below.

David Peters
davidpeters@att.net

Mike H. wrote: > Ground effect doesn't help quite that much.

Then why does every big bird launch I've ever seen include it?
It seems like a good way to accelerate AND fly. Such a system requires 
a less
powerful takeoff.


Mike H. wrote: > Besides, a biped launch doesn't get many pterosaurs 
even close
to cruise speed

And with ground effect acceleration, it doesn't need to. That's the 
point, I
think...