SAUROPOD STONES

[darren.naish@port.ac.uk]

Gillette hypothesises that the type and only known specimen of 
_Seismosaurus hallorum_ died after choking to death on a big stone.
 Patrick Norton, I think, wrote...

> I remember that grin. And next time that documentary is aired, take 
> a   close look at the alleged "choking" stone. It appeared to me to 
> be as   rounded and polished as the other supposed gizzard stones. 
> Difficult to   explain if the stone never made it to the gizzard.  

Well, as I understand it, Gillette says that sauropods stored stones 
in two places - in their crop (located at base of neck) and in their 
gizzard. Apparently the taphonomy of _Seismosaurus_ shows that the 
stones burst from both locations during decomposition. As for the 
roundedness of the supposed 'choking' stone, how polished it was may 
be irrelevant as the animal may have been picking up rounded stones 
in any case. It has been implied that the 'choking' stone was found 
in the crop or cranial to it. As you can see from the photos, it's a 
good deal bigger than the others in the assemblage.

A random thought.. supposed moa gastroliths were verified as being 
moa gastroliths because the light-scattering properties of 
gastroliths differ from those of (otherwise indistinguishable) 
polished stones. Has anyone thought of extending this method to other 
dinosaurs? The moa work was published in _J. Paleo_.

"Look at the size of that thing!"

DARREN NAISH
darren.naish@port.ac.uk