Re: *Mauisaurus* vs large pterosaurs

[Dann Pigdon <dannj@alphalink.com.au>]

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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