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Re: New Dinomorph site
I had a look at Kent's new Dinomorph website and -- you will all be shocked
-- I was not a happy visitor.
K continues to claim that giraffe necks are sharply dorso-flexed at the neck
base when I (at 06 SVP) and Christian & Dzemski (Fossil Record 07 10: 38)
showed that giraffe necks often articulate more horizontally, or are even
downcurved, apparently depending on the thickness of the intercentra cartilage
discs
which have since been lost or dehydrated.
K continues to assume that all sauropods have thin cartilage intercentra
discs even though we know from some dinosaur specimens that the discs were
often
if not usually thick (just about the only useful information to come out of the
dreadful Natl Geo show on the heavy tailed edmontosaur), as they often are in
giraffe necks which like sauropods have ball and socket centra articulations.
K continues to claim that the AMNH fused cervicals of Camarasaurus articulate
in a nearly straight line, and that they lay nearly flat on the table. As I
showed at the 06 SVP both statements are patently false. The two cervicals
would easily rock if the parapophyses were removed. K makes no attempt to
actually
measure the angle of dorso-flexion of the centra, perhaps because if that is
done as I did at the 06 SVP they are clearly flexed upwards ~10 degrees (the
strong flexion is easily visible in his own posted photos). That is far from
straight. K's claims are not science, they are propaganda.
Assume that the rest of the neck base vertebrae were also dorso-flexed
the same amount and the neck would angle upwards 45 degrees or more. The only
way to get an adult camarasaur neck to be straight with the zygapophyses in
full
articulation is to assume extremely thin intercentra cartilage discs that are
unlikely in the chronically poorly ossified sauropods. There is a bad need,
BTW, to get the fused AMNH cervicals CT scanned, it's the only way to see if
they are in or near neutral articulation, how thick the cartilage disc was, and
to what degree they may be laterally flexed. In any case, when K continues to
claim that camarasaur cervicals were normally straight when there is no hard
evidence this is true, and when the only hard evidence indicates otherwise,
reveals a detachment from the objective situation.
K continues to claim that the Carnegie Apatosaurus cervical series is
essentially straight when doing so requires disarticulating some cervicals as
can be
clearly seen in his own illustrations based on the figures of 3018, and when
the neck base vertebrae are so incomplete and distorted that the originals are
not on the mounted skeleton (they were replaced with sculpted models, thanks
to Jack McIntosh to pointing this out to me). The use of the neck of this
specimen to restore cervical posture is completely inappropriate and must be
abandoned, and continuing to use 3018 is scandalous.
As nice as the classic illustrations of the Carnegie apatosaur vertebrae
look, the degree that using them to try to restore their posture is dubious
can be seen by trying to do so with the dorsals of CMNH 563 (now at Laramie).
It
is simply not possible, they won't fit together in a normal manner. This does
not mean that apatosaurs had erect necks, but there probably is no preserved
neck that was well enough preserved and properly collected to tell for sure.
K continues to claim that the Euhelopus neck articulates in a straight line
when in his own version of the articulated cervical series it can be seen that
one of the cervo-dorsal articulations is ventro-flexed many degrees at the
zygapophyses! Rotate that joint so the zygapophyses are fully articulated and
the
neck slopes upwards by about the same amount Wiman originally restored it in.
K, in another egregiosuly propagandistic act, also slaps one of those red NO
signs over my restoration of Euhelopus even though the neck posture shown is
entirely within the range acheiveable with only a few degrees of dorso-flexion
between each of the posterior cervicals. K continues to be a member of the
rigid cult that for some strange reason thinks that all skeletal restorations
must show the neck in an osteological neutral posture. If that arbitrary rule
were applied consistently then the tail and legs would have to be in neutral
posture too -- no more tails in graceful flexions, no more running poses with
one
leg maximally extended in the push off and the other flexed in the recovery
stroke.
Apparently K plans to attempt a detailed restoration of the neck posture of
the Berlin brachiosaur SII even though the cervo-dorsals lack the upper halves
and are somewhat crushed. It is simply not possible to even try to restore
neck posture when the zygapophyses much less the cartilage discs are absent, it
is a completely useless project that not one more second should be wasted upon.
K also seems to think that researchers in the past have denied that
brachiosaurs fed at shoulder level. It is common knowledge that many herbivores
regularly feed at any level they can readily reach.
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