Re: Testing the "why" of Giraffe necks...

[MICHAEL HABIB <habib@jhmi.edu>]

> a higher atmospheric pressure would "reinforce" the artery 
> wall by increasing the ambient pressure acting on the external wall. 

Hmmm...interesting thought.  Are you sure this is the case, though?  I'm not 
sure how much of the pressure on the walls of internal vessels really depends 
on atmospheric pressure.  High pressures can certainly compress superficial 
vessels (and low pressures can cause them to dilate or burst), but I'm not 
certain if the carotids, for example, would react much to atmospheric changes.  
Any thoughts?

Cheers,

Mike H.