STEGOSAUR TAILS (WAS DUCKBILL NECKS)

[Brian Franczak <franczak@ntplx.net>]

Peter Von Sholly wrote:
> 
> And nobody ever noticed this before (in the old days) when they were
> putting stegosaurs together?  Besides, as long as they articulate with the
> angle of the spine, they could slope gently downward, NOT dragging on the
> ground, no.  I maintain there is some leeway in how bones can be put
> together.  Some.  Sometimes.  I was told once by a preparator who shall
> remain nameless that he was very excited about the new stegosaur tail
> orientation and wanted to be the first (or one of the first) to have his
> museum's specimen mounted that way-  but the funny thing was, it wouldn't
> GO together that way.  I asked how it DID want to go together and he said
> it had a natural, but gentle, downward slope to it.  Now, he may have been
> wrong, but that's what he told me.
> I NEVER saw stegosaur tails like that anywhere until Steve Czerkas came out
> with his and Greg Paul picked up on it and suddenly it was no other way!
> (I assume Czerkas was first, then Paul-  if I am wrong, let me have it).
> But I do like the Von Shollywood part...

USNM 4934 (the Smithsonian's famous "roadkill" stegosaur) shows a
good-sized tail fragment that is straight. Ken Carpenter's DMNH
stegosaur (the one that indicated the positioning of the dorsal plates)
has an in-situ tail that Ken personally described to me as "ram-rod
straight" from the hips.

As for why "nobody ever noticed this before (in the old days) when they
were putting stegosaurs together", why would they? The mounting of
dinosaur skeletons in "the old days" was not as accurate a "science" as
it should have been. Thus we had Dollo, who thought it was perfectly
acceptable to actually *break* the tail of _Iguanodon_ to get the mount
into the upright, kangaroo-like pose that he thought was right. And one
of the most-seen dinosaur images in history is the AMNH _Tyrannosaurus_,
which stood upright and tail-dragging until just a few years ago. (Sad,
actually, that they left the _Anatotitan_ pair in their old pose, as
well as their _Stegosaurus_.) 

When it was a fixed idea that dinosaurs were nothing more than
tail-dragging reptiles, that's the way they were consistently
interpreted. No one questioned it, and the fact that dinosaur
paleontology was a rather moribund science for quite a long time only
perpetuated those notions. With the resurgence of interest in dinosaurs
in the past few decades, more and better research has revealed a
different interpretation. Does this mean that in another 20 or 30 years
that *this* interpretation will be supplanted? Not necessarily, and IMO,
not likely. The evidence supporting these "modern" interpretations is
good. That's why they're so common.

Brian (franczak@ntplx.net)
http://www.paleolife-art.com