Re: Gliders to Fliers? (Was Re: Ruben Strikes Back)

[Dinogeorge@aol.com]

In a message dated 9/23/99 3:28:20 PM EST, mbonnan@hotmail.com writes:

<< If birds are descendants of small arboreal archosaurs (dinosaur, 
 non-dinosaur) which were gliders, how do you think the decoupling of both 
 the forelimbs and hindlimbs took place?  Am I missing something: are there 
 gliders which do not use both limbs with a sheet in between?
 
 Just curious, and you know what they say about curiosity and that cat. =) >>

In my present scenario, the feathered tail was the first aerodynamic surface 
to develop in the archosaur-to-bird lineage (a la the popular reconstruction 
of Cosesaurus as a tail glider), and this took the place of a uropatagial 
gliding surface/membrane, with the short, still sprawling legs tucked away 
beneath the body. If your aerodynamic surfaces are made of feathers rather 
than a membrane, they are self-supporting and don't have to be stretched 
between arms and legs to work.

Later, >once the wings developed<, the hind limbs would have become longer 
and stronger for running takeoffs from the ground, so that the dinobird would 
not first have to climb into the trees to become airborne.

This is a >very< interesting point; thanks for bringing it up.