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Re: new boook on functional morphology
> On Thu, 18 Jan 1996, Ronald Orenstein wrote:
> > could we not consider it possible that for
> > some purposes (possibly including head-to-head shoving matches) ceratos
> > might have adopted a sprawling posture that was not used during normal
> > walking?
Certainly, there is no way, short of a trackway showing a fight,
> > So if all Ostrom did was to show that the pectoral girdle was consistent
> > with a sprawled posture (say), then one could speculate that such a posture
> > was used - but NOT while the animals were busy laying down trackways.
> I BELIEVE that Johnson and Ostrom claimed that the structure of
> the ceratop(s)id pectoral girdle was *inconsistent* with an erect gait
> (i.e. that the bones did not fit right when put together in an upright
That is also my understanding of their results.
Given the narrow gauge of the front feet in the trackways, J&O's
results cannot be correct as stated. The feet are held closer
together than they claim is *possible*.
It is true that a bow-legged walking posture is consistant with
the trackways, just barely. But the contortions the front limb
would have to sustain in this position make me hesitate to accept
that conclusion. The reason is the the toes point slightly outwards
in the trackways. In a bow-legged position, the natural position for
the manus would be for the toes to point *inwards* (try holding your
elbows splayed out, with your hands in front, and then turn your
hand so the finger point out - OUCH).
The peace of God be with you.