Re: Biomechanics

["tons" <tons@logicsouth.com>]

I believe you are right Toby in that there would be little difference in the
air pressure.  It would be the change in atmospheric pressure near the
surface of the water (whatever that is above sea level) vs. what it would be
if the animal could stand on shore.  That's not much difference.

Also the animal could breathe with most of its body submerged if it had
enough muscle to push water out of the way by what ever means a sauropod
breathed.  I believe it would have more than ample power because it was a
huge animal.

This all relates back to dead space in the airway discussed some time ago.
Humans are not able to snorkel with too long a line because we are not used
to adding that much dead space to our air column.  We cannot eliminate CO2
adequately if there is too much dead space.  Sauropods are or more correctly
were able to handle it somehow.

Best

Michael Teuton
----- Original Message -----
From: Toby White <augwhite@neosoft.com>
To: <dinosaur@usc.edu>
Sent: Monday, September 06, 1999 10:49 PM
Subject: RE: Biomechanics


>
>
> On Monday, September 06, 1999 6:17 PM, Ralph W. Miller III
> [SMTP:gbabcock@best.com] wrote:
> > Two questions for the engineers in the crowd...
> >
> > First, what figure would you put on the pressure at the level of the
lungs of
> > a
> > large, submerged, snorkeling _Brachiosaurus_ individual with the lungs
about
> > 20
> > feet (a tad over 6 meters) below the water level?  Can this be put in
terms
> of
> > psi
> > (pounds per square inch)?  I'd appreciate seeing how you arrived at
this, and
> > no,
> > you're not doing my homework.  I'm not enrolled in school at this time.
I
> > understand that the water pressure would be too much to enable the lungs
and
> > air
> > sacs to expand, but I would like to see the predicament quantified.
>
> If snorkling -- i.e. with air in lungs in contact with atmosphere, would
there
> be any pressure differential?
>
> > Second, it has been stated recently on this list that a fast running
> > _Tyrannosaurus
> > rex_ individual (was it 20 meters per second?) would trip and fall on
its
> > skull
> > with the force of a bus impacting a brick wall at approximately 60 mph.
I
> > understand such a hypothetical tyrannosaur was calculated to have
sustained
> > fatal
> > injuries.  My question: is the 60 mph bus analogy apt?
> >
> > -- Ralph W. Miller III       gbabcock@best.com
>
> 20 m/sec seems a bit fast, even for the hottest of hot-blooded dinosaurs.
As
> well, I think the average city bus is somewhat more massive than the
average
> tyrannosaur.  Would you accept a Suburban going, perhaps, 30 mph?
>
>   --Toby White
>
>