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On Wed, 11 Dec 1996, Robert J Meyerson wrote:
> >Muscles need area's to attach to, right? IF the jaw muscles attached to
> >the frill like you say, on the frill, around the fenestra, there is a
> >BIG problem. The middle of the muscle has to attach to something but
> >there is a hole, there is NOTHING there to attach to. It wouldn't work.
> I don't see the problem in this. I envision the jaw muscle being similar
> to the strap on my backpack: Long but thin, with the long muscle fibers
> oriented with the long axis of the muscle. In this senario, the muscle
> bulges through the fenestra as the animal chews. This is not an outlandish
It probably is. Longer muscles can contract over greater distances, but
the strength of a muscle is directly related to it's cross sectional
area. This is why modern herbivores tend o have short, broad sheets of
muscle to pull om the jaw; because it develops much more force.
>, the earliest mammals had a single, small fenestra located at the
> temples. In modern mammals, this fenestra has opened considerably,
> allowing the muscle to bulge unhindered by the bone as the animal chews.
The earliest mammals, it was my impression, were really tiny
and probably ate bugs, small animals, or seeds. Making arguments about
the functional anatomy of a 5 tonne grazer from the anatomy of a tiny
insectivore not even related to doesn't make a lot of sense.