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RE: Parrish's neck work ...
On Saturday, May 01, 1999 1:17 AM, Frank Galef [SMTP:firstname.lastname@example.org]
> If they were to rear up, or put their heads down, blood pressure would
> have been a problem. I'm not sure it would have been insurmountable.
> Retes to serve as capacitance vessels could have served as buffers to the
> pressure, as could powerful muscles within the walls of the arteries
> themselves. It will be hard to find enough soft tissue to prove this in
> any case.
Hmm. I try not to speculate too much on-list, but your comment generated a
couple of ideas:
1) Perhaps our model of sauropod behavior ought to be that one or a few
sauropods establish themselves on a spot, plant their feet and then swing their
necks about, stripping everything green within reach until forced to move on by
lack of further greens. The neck then is advantageous because the longer the
neck, the less frequently the beast needs to expend the huge amount of energy
necessary to move the rest of the body from one place to another. Far from an
active "Heigh-o Silver and Away!" lifestyle, they lived more like occaisionally
2) Finally a plausible use for the space in all those hollow vertebrae! Blood
sinuses? Muscle attachments for ancillary blood pumps?
and a question:
It might be logical to assume that food in the elongated esophagous would have
to be moved along by strong, almost continuous peristaltic contractions. Could
those same contractions be used to move blood along without the embarassment of
creating ancillary hearts, a design which would amount a reversion to a
physiological design left behind with the Myxinoids?