AMNH Apatosaurus mount

[Mike Limonite <taradosgon@yahoo.com>]

Dear readers:

       Were the cervical vertebrae (particularly the
neural spines) on the AMNH mounted Apatosaurus found
along with the rest of the animal, made from scratch
(cervicals of that individual not found), or casts
from other Apatosaurus individuals?

When comparing the cervicals of the AMNH Apatosaurus
(#?), CM 563 (A. excelsus now mounted at the
University of Wyoming), YPM 1980 (A. ajax; originally
A. immanis, and CM 3018 (A. louise), I see that the
cervicals of the AMNH individual look more like those
of A. ajax or A. louisae.

For example, the postspinal laminae is not curved in
the AMNH specimen on the cervicals (at least the
anterior ones) I cannot tell (I'm looking at an old
photograph of the individual being mounted) if the
more posterior cervicals (last 3-4) have curved or
straight post spinal laminae. CM 3018 has flat post
spinal laminae, CM 563 and YPM 1980 do not. Also the
neural spines are  relatively tall, though not as tall
as those of CM 563 or CM 3018 or as short as those of
YPM 1980 (which are noticeably shorter than the other
two). However the postzygapophyses and neural spines
of each cervical (save the last 3-4) are level (the
tops of the neural spines are level with the
postzygapophyses).  This is more of a YPM 1980 trait 
though not exactly since there is still some
difference in height between the postzygapophyses and
neural spines (where as in the AMNH individual there
is none noticeable save in the last three cervicals).

Now I've tried comparing other parts of each
Apatosaurus species (limbs and such) but the vertebrae
seem to show the most contrasting traits. I stick with
the cervicals since I haven't been able to see the
caudals, sacrals, and dorsals very well (and from what
I've read alot of the dorsals and sacrals haven't been
preserved well in one individual or another which
would make comparison hard).

This leads me to believe that either:

*This animal does indeed represent a new species.
*The height of the neural spine in proportion to the
rest of the cervical, the appearance of the postspinal
laminae,  as well as postzygapophysis-neural spine
height comparisons are all subject to individual
variation.

though again, I do not know how many of those cervials
are actually real and how many were made from scratch
with guess work or if different parts from different
Apatosaurus cervicals were all fit together. The
picture I have is also of the animal being mounted the
first time. If the cervicals were made from scratch or
casts of other species did they refit the mount with
A. excelsus casts when they remounted it?
     

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