Re: Bipedalism and theorizing... was Re: Morgan and creationists
Gerrit Hanenburg (ghanenbu@inter.nl.net)
Mon, 30 Sep 1996 16:11:15 GMT
"John Waters" <jdwaters@dircon.co.uk> wrote:
>JW: For readers who do not have ready access to this book, I
>think we should make it clear that the photographs do not imply
>any long distance carriage of the infants comparable with (say)
>knucklewalking. In one case, the mother is attacking another
>female; while in the other case the mother is attacking a
>(stuffed) leopard.
Nevertheless it shows that an infant can cling to its mother in a
bipedal posture.Consider it as a possible model of infantcarrying
behaviour during a very early stage in the development of bipedalism.
>JW: I was not claiming that early bipedalism had to be
>particularly efficient; merely that it had to be capable of
>doing the job in hand. Therefore I entirely agree with your
>point about being *effective*.
>That said, going back to the previously quoted example of the
>chimp (faben) with the paralysed arm, it should be noted that
>such an arm is just so much dead weight. The arm would probably
>weigh about 5 pounds. This is about the weight of a new born
>chimpanzee infant. Which implies that if an nursing female
>carried her baby in her arms, twisting slightly to one side, the
>centre of gravity would be sufficiently favourable to allow the
>same long distance walking as was achieved by faben. Thought of
>the day?
The infant is an eccentric weight.So,twisting the body slightly to the
opposite side would result in the projection of the center of gravity
within the supporting surface formed by the feet,like we do when
carrying a bag in one hand or a child on the hip.
That is a requisite for maintaining balance,but long distance walking
requires more than just that.
Gerrit.
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