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Re: *Mauisaurus* vs large pterosaurs
On Thu, Oct 8th, 2009 at 8:50 AM, David Marjanovic <david.marjanovic@gmx.at>
wrote:
> > Further, an elasmosaur swimming below the surface in clear water
> > could accelerate at a positive angle of 25 or 30 degrees relative to
> > horizontal. Given a 15m neck, this would put the head approximately
> > 10 m above the water surface when the main body breached the surface.
>
> That would cause the poor animal to tilt over and hit its entire 15 m
> long throat, and the head, against the water surface. Hard. As in
> "once-in-a-lifetime experience", considering the fact that the head,
> while small, is dorsoventrally flattened.
>
> And why do you think that marine pterosaurs were plentiful enough to
> have an effect on elasmosaurid evolution?
>
> Besides, what about the recent finds of elasmosaurid stomach contents
> that indicate elasmosaurids were generalist bottom-feeders?
My thoughts exactly. Elasmosaurs appear to have been the vacuum cleaners of the
sea.
I also have my doubts that an elasmosaur could have held it's neck vertically
rigid out of the water
for *any* amount of time. Apart from structural concerns, the pressure
difference between head
and body would have been enormous. It's generally very hard to catch a
pterosaur on the wing
when you're unconscious.
--
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Dann Pigdon
GIS / Archaeologist Australian Dinosaurs
Melbourne, Australia http://home.alphalink.com.au/~dannj
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