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Parrish's neck work ...



Hey There:

Toby White said:
"Gads! What's next?  I predict computer models of sauropods whipping
their necks 
around and regurgitating gastroliths at hypersonic speeds to shoot
down 
formation-flying, pack-hunting maniraptorans [phylogenetically
bracketed -- in 
brackets, of course -- between Canadian Geese and F-14s]."

Well, I would suggest you read the paper in science.  I suppose I'm a
bit prejudiced as Mike Parrish is my adivser (I work on sauropod
locomotion) but I know Mike is very careful and tried to model the
cervical vertebrae as accurately as possible.  The basic premise is,
once the zygopophyses lock up, no more motion is possible.  This is
reasonable, since disarticulation of the zygopophyses in any
vertebrate's neck usually mean paralysis or death.  What is
interesting, I think, is the amount of ventriflexion (how far these
sauropods could bend their necks downward) that is possible -- you can
make Apatosaurus bend its neck so that its head is looking up at its
feet!  Obviously, these motions were constrained by living tissues
(ligaments, muscles, intervertebral discs and cartilages), but the
amount of motion possible in side to side and downward motions is
quite impressive.

What does this study mean?  Is Mike Parrish totally right? 
Absolutely not, and I know Mike would never claim that he was 100%
correct on anything -- this science is far too indirect for anyone to
claim they have "the answer."  Mike was in fact very surprised at the
results.

>From my own experience with sauropod limbs, sauropods become weirder
and weirder the more you deal with them.  They cannot be confidently
compared to any living vertebrate, except perhaps in simple, gross
form or shape.  Plus, remember that sauropod bones are gigantic, weigh
100s of pounds, are not easy to manipulate, and most of the good stuff
is mounted with lead and steel pipes running through and obscuring
valuable data.  This is why I'm glad Mike, his collaborater Kent
Stevens, and many other sauropod researchers are beginning to use
computers to finally articulate and move the bones around.

I wouldn't be too surprised if someone told me that they found a
sauropod with five legs and a rotary engine. =) Well, okay, maybe I
would, but the point is these animals are a pain in the butt to work
with, and anyone who tries to work with these big beasts has my
respect.

Matt Bonnan
Dept. Biological Sciences
Northern Illinois University