Sail vs Hump?

[Robert.J.Meyerson@uwrf.edu (Rob Meyerson)]

I just got back from the North-Central Section Meeting of the GSA, and heard
 an interesting idea that I thought I'd throw into the field for debate.

There are a wide variety of dinosaurs with greatly elongated neural spines,
 and each one of these is restored as having a Dimetrodon-style sail.  One
 speaker questioned this idea.  He compaired the neural spines between
 Dimetrodon (long, thin, tapiring) and the modern bison (blade like, thicker
 at the top than the bottom).  He then brought in several dinos with long
 neural spines to see which model is more accurate.  He concluded that the
 spines in all dinosaur cases were far more similar to the spines of a
 bison.  Therefore, dinosaurs with long neural spines should be restored
 with a hump, rather than with a sail.

On a semi-similar point, he looked closely at _Oranosaurus_ (sp?).  After
 adding the hump, he found that the pelvic region was located too far back
 to justify the idea of a bipedal animal (unless it was standing on a hill,
 with it's tail tilted downward:-).  He concluded that _Oranosaurus_ was
 fully quadrepedal.  Another interesting notion is that the pelvis of
 _Spinosaurus_ is located in a similar position to _Oranosaurus_.  If this
 is true, then _Spinosaurus_ would be the only quadrepedal theropod known.

Comments?

Rob

***
"What sad times are these when passing ruffians can say 'Nee' at will
to old ladies!"
                -MPATHG