Re: Triceratops running speed

[Graydon <graydon@dsl.ca>]

On Fri, Jul 27, 2001 at 09:42:37AM -0700, Jaime A. Headden scripsit:
[big snip]
> The forelimb has the ability to swing back and forth, and this
> lengthens the stride, but it is unlikely, given the hindlimb
> morphology, that the animal could have attained cursorial speeds
> of more than 30mph.

Has anyone done anything on the position of the head in ceratopsians
when feeding or walking?

Those huge skulls are on ball and socket joints at the end of a long
columnar neck; tipped down into a horns-level charging position, the
beak isn't going to very far off the ground.

I don't think there's a gait constraint to keep from kicking themselves
in the chin, but I do think there's very likely a gait constraint to not
osscillate their heads all that much; a gallop when a third of your body
length is head is going to present strong dynamic loads.

So it might not be just a question of what the legs can do; it might be
a tradeoff between speed and the feeding structure, and it doesn't seem
likely that there's an extant animal which provides a good model.

-- 
                           graydon@dsl.ca
               To maintain the end is to uphold the means.