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re:plesiosaur/pliosaur propulsion



I just tuned in to the discussion on this subject: my email address got (more th
screwed up.>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>[D

Unless this has been discussed already, let me add to the comments by Stan and S
s realized several years ago (I forget by who) that the elasmo-
saur plesiosua>[D>[D>[D>[D>[Diosaurs could not flex their necks in the manner pi
old
Charles Knight paintings, and thus they could not dart around and snag fish
or fight off mosasaurs by snakelike motions p>[Dof the head.

 Further, we also know that pliosaurs with modest sized necks (e.g. Cimoliosau>[
Aurus) were much more common than the exotic long-neckse>[D>[Ded plesiosaurs, at
In the Late Cretaceous.

 Therefore, the whole behavior of the Sauropterygians was reexamined and they ar
ly perceived to be penguin-type submarine flyers; both long- and
short-necked forms.  The body p>[Dplan of the entire group is fairly conservativ
except for the necks and heades>[D>[D>[Dds.  Betsy Nicholls at Tyrrell has a rec
He shoulder>[D>[Ders of plesiosaurs which points up the adapations for subaqueou
D>[D>[D flight, and she used the model of cheloniids (marine turtles) for analog
(ciart>[D>[D>[Dtation: Nicholls. E.L. and Russell, A. P. 1991, The Plesiosaur pe
girdle:the case for a sternum.  --o>[D>[Doscure journal: Nues Jb. Geol. Palaeont
Stuttgart, Germany p. 161-185--I'd just write to Betsy for a ciop>[D>[D>[D>[Dcop
B>[C>[C>[C>[C>[C>[C>[C>[C>[C>[C>[C>[C>[C>[C>[Cv. >[D>[D>[D>[D>[D>[D>[D>[D>[D>[D>

  Bottom line, as far as I know, plesiosaurs/pliosaurs were rapid swimmers
using turtle/penguiio>[D>[Dn type propulsion for pursuit predatioo>[Dn.
david schwimmer
schwimm@usd>[Dcn.cc.uga.edu (I think)