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Re: Testing the "why" of Giraffe necks...
Heh. "Wow, what a surprise" is the category I would put this in. Good that it
is done, though.
For those who don't object to a little speculation opposing the current null
hypothesis of 'steady-state' atmosphere, it might be interesting to note that
although the gravity force the heart would have to overcome to pump blood to a
given height would remain the same over time, a higher atmospheric pressure
would "reinforce" the artery wall by increasing the ambient pressure acting on
the external wall. If the limit of 'head-over-heart' height is the strength of
the artery rather than the pressure the heart can generate, a denser atmosphere
would therefore allow a longer neck (ie, a greater head/heart height
differential). By 'strength of the artery' I refer of course to the ability of
the artery to resist aneurysm due to a positive differential between internal
and external pressure (internal p - ambient p > 0).
----- Original Message ----
From: Guy Leahy <email@example.com>
Sent: Saturday, December 23, 2006 10:02:22 PM
Subject: Testing the "why" of Giraffe necks...
Interesting research... with obvious analogies to