[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Plesiosaur question

In a message dated 99-03-08 13:02:47 EST, you write:

 In Prehistoric Times (I think), they had an article on last year's
 discoveries.  One was on a plesiosaur that had stomach contents
 intact, several amonites.  The article indicated that 1) plesiosaur
 teeth couldn't crack the shell, 2) that the amonites were found in
 the area of the stomach cavity intact with no sign of shells, and
 concluded that stomach acids had disolved the shells.  

  I don't know the original source for this, but certainly the plesiosaur's
stomach acids would make short work of the ammonites' calcium carbonate
shells. Same thing happens to aquatic snail shells when ingested by modern
sunfish. I believe other finds of stomach contents consisting of cephalopod
beaks have been made. 
  Perhaps the author was thinking of the rounded teeth of the mosasaur,
Globidens, as a specialization for processing shellfish. Globidens' closest
relative, Prognathodon, is the prime suspect as the ammonite-eater in
mosasaurs yet has stout but pointed teeth. The main idea is to gain entry to
the living chamber of the ammonite by biting or crushing followed by removal
of the organism. I see no reason to prevent some of the plesiosaurs from doing
this also. Dan Varner.