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<Not to disagree with you about _Protoceratops_, but other ceratopsians
are also usually portrayed with sprawling fore-limbs.>
So were sauropods, stegosaurs, and ankyolosaurs, but that didn't mean
the idea was correct. Back when everyone though dinosaurs were just
giant lizards (as recently as a few decades ago) they reassembled the
limbs to reflect this, even ignoring the joint articulations in favor of
their assumptions---take Hawkins' restoration of *Iguanodon* and
*Megalosaurus*, ignoring the perforate acetabulum and supracetabular
shelf and the structure of the femora. Owen wanted sprawl, Hawkins saw
that this would be impossible, and restored accordingly.
The sauropod sprawl even went so far to try to be the explanation for
glacial trenches, supposed "rubbing out ruts" into the ground. They
ignored the limb structure and articulations.
<I know that when Ken Carpenter originally tried to assemble the copy of
Chasmosaurus here at the Academy of Natural Sciences (back around
1984-1986), he wanted to place the fore-limbs directly under the
centerline of the animal. He was unable to do so, because the 'elbows'
would bang into the rib cage if the animal would gallop.>
This may actually be the source of the whole mess. Trying to theorize
that ceratopsians could gallop: if their limbs didn't allow it, then
they didn't do it, but to gallop, they would have to go bent-elbow.
Otherwise, a strait limbed ceratopsian didn't gallop, and the reason why
some paleontologists believed they didn't do that. Take Bakker's
galloping *Montanoceratops*: it is restored running with the elbows
Or an elephant: running (or fast walking) strait legged, it is faster
than a man. Trikes didn't neccessarily need to run from predators, for
while those horns may have primarily served as courtship or
interspecific rivalling tools, they could also be used as weapons, and
the same goes for those fantastically huge and powerful beaks, the
strongest jaws in all dinodom.
<It seems that the fore-limbs need to 'partially' sprawl to allow for
the most complete movement of the limbs. As I said, I haven't checked
the _Protoceratops_ skeletons lately with this idea in mind.>
The ulnar condyle is set slightly lower than the radial condyle on the
humerus. That's as much as I've gleaned so far.
Jaime A. Headden
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