Re: FW: 6th International Congress of Comparative Physiology and Biochemistry (long)

["Tim Williams" <twilliams_alpha@hotmail.com>]

> Hillenius, W.J.
>
> There is no credible evidence to support the reconstruction
> of a derived, avian-like parabronchial lung/air sac system
> in dinosaurs. [snip] The avian parabronchial lung/airsac system appears to 
> be an attribute of ornithurine birds.

Now that's interesting, since it flies in the face of evidence (published by 
Britt et al. [1998] and Bonde and Christiansen [2000]) etc) that 
_Archaeopteryx_ had cervical air sacs, and perhaps abdominal air sacs as 
well.  Further, the presence of pneumatic foramina ("pneumatopores") in the 
vertebral column of tetanurans (especially oviraptorosaurs, where it 
continues into the tail) suggests the presence of diverticula - meaning that 
tetanurans had already developed some aspects of the avian respiratory 
system prior to Ornithurae.

Anyway, to respond to Jordan's query, Carrier and friend's work on rotation 
inertia in theropods has been published:

Carrier, D.R., Walter, R.M., and Lee, D.V. (2001).  Influence of rotational 
inertia on turning performance of theropod dinosaurs: Clues from humans with 
increased rotational inertia.  Journal of Experimental Biology 204 (22): 
3917-3926.



_________________________________________________________________
Tired of spam? Get advanced junk mail protection with MSN 8. 
http://join.msn.com/?page=features/junkmail