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RE: Sue Photos Online (Good ones!)



there's only so much you can do with a
fossil or cast without adding to the restoration. The quadrates were
splayed quite a bit in the actual skull, and it would have taken
considerable breakage to fix all of it...This is also why the ribs >aren't swept all the way back, as an earlier
commentator observed. This was not an oversight on our part - the rib
heads and vertebral transverse processes are all distorted. Had we
articulated the ribs perfectly, the trunk would have been twisted to >the left...Remember, when mounting real bones, one has to deal with >postmortem distortion. We wanted to minimize restoration on the bones >- restoration covers up what's actually there, and we wanted to keep the bones as pristine as possible for future researchers.

This, of course, brings up the old mutual exclusivity of mounting real vs. cast bones. Casts, if made properly, can undergo a sort of "antidiagenesis," in which diagenetic distortions are undone via the plastic properties of the casting material. Mounts certainly look much, much nicer when distortions are corrected for -- it's more of that "the animal just died yesterday" sort of mount, like one would expect in a mounted skeleton of an extant animal. I personally prefer these mounts. However, mounting real bones shows the public what kinds of ravages time and physics imposes on fossils and, although never pointed out directly, implies to them what paleontologists have to go through to mentally undistort bones to properly interpret them (as we've seen here with the discussions about the skull shape in "Sue"). The mounts aren't nearly as pretty, but are more "real" in that sense. Although I've not seen it done, it would be nice with said mounts if signage were put with the mount explaining why it looks lopsided, why the ribs aren't quite right, etc., and then have pictures of what the proper, restored bones _would_ look like.


Also, the public, in my experience, frequently just assumes -- and probably expects -- that _all_ mounts are 100% real bone, even when they're actually casts (undistorted or not). Given this, I'm not much for mounting real bone, or, alternatively, mounting casts (which are easier to mount, anyway) and then putting the real bones beneath the mount so both can be viewed -- it's easier for scientists to study them this way, too. I have, however, done it both ways. I am somewhat curious as to how much it was debated at the FMNH to mount real vs. casts of "Sue," and what the deciding factors were....?

  Just my $0.02...

                _,_
           ____/_\,)                    ..  _  
--____-===(  _\/                         \\/ \-----_---__
           /\  '                        ^__/>/\____\--------
__________/__\_ ____________________________.//__.//_________

                     Jerry D. Harris
                 Fossil Preparation Lab
          New Mexico Museum of Natural History
                   1801 Mountain Rd NW
               Albuquerque  NM  87104-1375
                 Phone:  (505) 841-2809
                  Fax: ; (505) 841-2808
           >>>>> dinogami@hotmail.com <<<<<

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