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Re: Knucklewalking
Erin Miller (ermiller@tezcat.com)
19 Jun 1995 11:17:34 -0500
In article <herwin-1906950719110001@192.0.2.1>,
Harry Erwin <herwin@gmu.edu> wrote:
>I went through Tuttle's article on the subject in Primate Functional
>Morphology and Evolution. Very interesting! Orangs knucklewalk in addition
>to fist walking when they spend time on the ground. It's not as optimized
>as in Pan and Gorilla, where the hand has been modified to handle the
>stresses. On the other hand, I understand the small apes tend to be
>bipedal, since they don't need the forelimb support as much. Morphology
>tracks behavior, but at a distance! All this tells us that early hominids
>probably used knucklewalking at times (when forelimb support was needed)
>and abandoned it under some sort of selective pressure.
Look at the morphology, tho. The great apes' torsos are such that their
center of gravity (balance?) is up in their rib cages, causing the body
weight to fall forward, hence knuckle/fist walking, or any quadrpedal
movement, on the ground is logical. But both gibbons and humans have a
lower center of gravity, so their upper bodies would not naturally fall
forward. Thru electromyography, gibbons have been shown to expend LESS
energy walking bipedally than even when brachiating (i'll have to get the
cite later, sorry). When hominids first came to the ground, they were
probably gibbon-like in size and torso anatomy, so I'd be surprised if
they knuckle-walked any more so than the gibbon does, which it doesn't.
-erin
--
"On the internet nobody knows you're a dog ...
but damn if everyone won't know what your cat looks like." -fatz
Erin Miller http://www.tezcat.com/~ermiller/erin.html
University of Chicago / Anthropology Department / ermiller@tezcat.com
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