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Re: pterosaur tracks from SVP



Ah, indeed I didn't pick up on your meaning.  Yes, in your sense, they are
front heavy.  The pectorals and arm muscles are quite massive and comprise a
large fraction of the animal's total mass.  You're also right in that there
ain't much behind the hips for counterbalancing while on the ground.  My usage
of  'front' referred to below to was just the neck and head.  The bone wall
thicknesses in Qn range from roughly 1mm up to about 4mm.  In Qsp, they range
from about 0.7mm up to about 3mm, so both have quite thin compacta.  For
comparison to gross size, the Qn humerus at the elbow measures 9.2 inches from
top to bottom, and is about 21-22 inches long.

Larry Febo wrote:

> >> >In a forward momentum, the apparently overweighted front end would
> >> not be a problem.<
> >>
> >> ???  The front wasn't overweighted.  Perhaps I didn't pick up your
> >> meaning.
> >
>
> I meant everything front of the hip joint seems heavier than everything
> rearward in pterodactyloids (minus the long counterbalancing tail). I know
> Padian states that the wing bones are deceptively lightweight due to air
> spaces , but, there were flight muscles attached that weren`t lightweight
> ...no? They seem obviously front heavy to me.