Re: Blood flow in Sauropods

[Stan Friesen <swf@ElSegundoCA.ATTGIS.COM>]

>From: Jeffrey Martz <martz@holly.ColoState.EDU>
 >      Although I am certainly among the skeptics concerning the idea of 
 > diplodocids feeding in a tripodal arrangement, I don't think the idea 
 > is totally implausable. Certain types of sauropods such as Brachiosaurus 
 > and Omeiosaurus propably held thier heads up pretty high anyway.

I do not know of anybody who has suggested "tripodal" feeding for
any group except the diplodocoids (diplodocids, dicraeosaurids,
and *perhaps* the titanosaurids).

The neck articulation in the brachiosaurids is "vertical", and thus
puts the neutral head position quite high.  They clearly fed at
heights above 30 ft.

 >  I don't 
 > think anyone will suggest that Brachiosaurus was feeding on low lying 
 > vegetation because it couldn't get blood up to it's brain.

Actually, the only sauropod for which I have heard a reasonable 
argument for low feeding is Apatosaurus itself.  It has the "horizontal"
neck articulation of a diplodocid combined with a heavy body that
probably couldn't achieve the tripodal stance.  I suspect its long
neck is a retention from its diplodocid relatives.

[Note, giraffes normally feed high in the trees].

 > Elephants ... aren't really designed to go upright, but 
 > they can do it anyway.  Stegosaurs on the other hand have a little head, 
 > massive dorsal vertebrae, and a nice, big tail.

Yep, and similar arguments can be applied to the typical diplodocids.

swf@elsegundoca.attgis.com              sarima@netcom.com

The peace of God be with you.