Re: Microraptor biplanes?

[Michael Habib <mhabib5@jhmi.edu>]

> The primary reason he illustrates the leg in
> this position, for the purpose of "flapping", can be ignored if the 
> extended
> leg (given the muscles as in birds, would this be physically possible?)
> provided aerodynamic reasons to be extended, without flapping.

I'm not sure if you mean the extended leg or the flapping leg when you 
ask if it would be possible.  Modern birds can extend their legs 
straight backwards from the knee down, but the femur will always point 
forward in flight (and cannot rotate much past vertical).  However, 
Microraptor, to the best of my knowledge, still retained the theropod 
femoral position (rather than a derived bird femoral alignment).

As for the flapping, 'twisting' in the legs is very limited in birds.  
Nearly all motion is restricted to parasagittal motion.

Cheers,
--Mike Habib