Re: Bipedalism and theorizing... was Re: Morgan and creationists
Gerrit Hanenburg (ghanenbu@inter.nl.net)
Mon, 30 Sep 1996 16:14:46 GMT
Paul@crowleyp.demon.co.uk (Paul Crowley) wrote:
>> I do not disagree with the "common" view,I simply propose an early
>> intermediate stage during which a habitually bipedal hominid still
>> carries the infant in ventral position,possibly pressing it close with
>> one hand while proceeding on the ground.
>Such an animal still has very great disadvantages compared to its
>fully quadrupedal cousins -- especially in a woodland habitat.
>It's very hard to see why it should choose to go about in such
>a awkward manner.
To feed maybe?
According to research by Kevin Hunt at Gombe and Mahale 80% of
chimpanzee bipedalism is within the context of feeding.(see reference
in an earlier post)
>Surely all the selective pressures are towards regaining a fully
>normal primate ability to cling properly? The ones that can't,
>are likely to fall off and die. And their mothers have much more
>difficulty feeding, or fleeing.
Not if the hominid infant was as precocial as a chimp (which seems
likely for Australopithecines given the similarity of lifehistory
variables such as the pattern of tooth eruption and brainsize) and
able to cling when necessary.
>When you go to a zoo (or look at a photograph in book) often the first indication you'll
>get that a primate mother has an infant is the sight of its hands
>and feet on the mother's *sides*. It's as though she had four
>small patches stiched on. They, with the infant's legs and arms,
>act as clamps on her body. Primate infants have remarkably long,
>muscular arms from the day they are born, just for this purpose.
>All this is obvious to anyone who looks. That's why there is
>little point in debating it.
Goodall looked (many years at close range),Schaller looked,I looked.
Conclusion:infants up to the age of 2 years cling to their mothers by
gripping the hair between flexed fingers and toes.
Case closed.
Gerrit
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