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Re: sauropods: homotherm,heterotherm or gigantotherm?



> Date: Thu, 15 Sep 2005 11:30:30 -0400
> From: "W. F. Zimmerman, wfzimmerman.com" <wfz@wfzimmerman.com>
> 
>> That is a very strange paper.  Its figure 3a suggest (in agreement
>> with Greg's message) that the locomotion of terrestrial mammals is
>> indeed about five or six times as energetic as that of similarly
>> sized fish; but that marine mammals are about as efficient as
>> terrestrial mammals.  The bizarre but inescapable corrolary is that
>> fish locomote at a sixth the energy cost as same-sized marine
>> mammals.  Can that really be true?  Are dolphins that crap?
>
> Dolphins do get their air from a completely different source which
> requires regular penetration of the air-sea barrier.

But that is not necessarily an inefficient thing to do.  Au and Weihs
(1980) even suggested that ... well, the title of their paper is "At
high speeds dolphins save energy by leaping" (Nature 284: 548-550),
which pretty much speaks for itself.  I certainly don't see how
periodic (and rare) surfacing for air would account for a factor of
six in locomotory efficiency.

Something is fishy here.

 _/|_    ___________________________________________________________________
/o ) \/  Mike Taylor  <mike@miketaylor.org.uk>  http://www.miketaylor.org.uk
)_v__/\  Since Oscar Wilde's quote "There is no sin except stupidity"
         is clearly stupid, we should probably consider it sinful in
         deference to him.