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Re: DinoMorph Strikes Back!... or does it?
This may all be part of the "Dinomorph Project", but let's not confuse
this with computer reconstructions done using the Dinomorph software.
This is Photoshop manipulation of illustrations; frankly, it's no less
"artistic" than the other reconstructions that are lamented on the same
Photoshop composites depend strongly on the accuracy of the
illustration (sort of hard to quantify off hand...), and any errors by
the original artists will be faithfully passed on in the Photoshop
composites. Another, more intractable problem is that the search for
"wedge shaped" centra in procoelous vertebrae cannot be done simply by
looking at lateral views of the centra. Mechanically speaking, the
"wedge" or "keystone" shape that causes an upward (or downward) arch
arises from the articulation of the centra. Since sauropod cervical
articulations are convex/concave, this cannot be ascertained simply by
looking at the posterior rim of the centra.
The Dinomorph Camarasaurus page credits the Wyoming Dinosaur Center as
having mounted a Camarasaurus with a neck in the horizontal posture
"very much in agreement with the osteological evidence", the skeleton
was in fact mounted that way because of the media exposure the
Dinomorph project had received. To do so resulted in a gap between the
zygopopheses of the anterior dorsals that you could shove a man's thigh
through, see here:
In light of the unacceptability of this, we recently remounted it in a
closer approximation of articulation. This resulted in an upright neck,
albeit not one as upright as Greg Paul used to restore. A
photomanipulation of the actual bones that was used to figure out how
we had to changes the armature can bee seen here:
Unfortunately we were constrained to modifying the existing armature,
so the bones are perfectly articulated. That said, it is much closer
now than it was in the neck-straight-out position. We are in the
process of scanning all the bones into 3D computer space, but
manipulation of the bones in a sand box confirmed that there was no way
to keep the anterior dorsals in articulation and have the neck coming
straight out at the shoulders.
Kent is doing some exciting work, but manipulating drawings in
Photoshop has its own share of error sources. It's worth pointing out
that it isn't simply "artists" who have argued for an upright neck
posture in some sauropods. Per Christiansen, among others, has
published biomechanics arguments that support this interpretation.
Don't get me wrong, the jury is still out on how many (if any)
sauropods held their necks upright, and if so, how high. But Photoshop
manipulation of drawings is no stronger a form of evidence than the
skeletal reconstructions that proceeded the technique. What we really
need are good 3D data sets from well preserved and complete specimens.
Hold the phone on that request...
Wyoming Dinosaur Center
110 Carter Ranch Rd.
Thermopolis, WY 82443