RE: A New Hypothesis for the Origin of Flight?

["Williams, Tim" <TiJaWi@agron.iastate.edu>]

David Marjanovic wrote:

> Possible. But very flexible arms and hands would be very advantageous
> here.  I don't see them in any described dinosaur 

In fact, the closer one gets to birds in theropod phylogeny, the more
constrained the motion of the forelimb becomes and the less prehensile the
manus becomes.  This would seem to argue against primate-like leaping
between trees.

>(will be interesting to read what the aye-aye dino has... no, that's not 
> a prediction, I  don't know it :-)

The striped possum (genus _Dactylopsila_) from northern Australia and New
Guinea also shows an elongated digit on its hand, used for much the same
purpose as the aye-aye (_Daubentonia_) of Madagascar.  However, in
_Dactylopsila_ it is the fourth finger that is elongated; in the aye-aye it
is the third finger.



Tim



------------------------------------------------------------ 

Timothy J. Williams 

USDA-ARS Researcher 
Agronomy Hall 
Iowa State University 
Ames IA 50014 

Phone: 515 294 9233 
Fax:   515 294 3163