Re: An alternative to ST and AAT
Paul Crowley (Paul@crowleyp.demon.co.uk)
Tue, 19 Nov 96 23:28:28 GMT
In article <848317256snz@crowleyp.demon.co.uk>
Paul@crowleyp.demon.co.uk "Paul Crowley" writes:
> > >What could Lucy do that H.erectus couldn't?
A way of looking at this problem might be to regard the modern
human shape as something outlandish compared to normal apes
(those rear limbs taking up one third of body weight) and
think of the activities (other than living in trees) which
Australopithecines would find difficult with such limbs.
One would be sitting. If Lucy had to spend a lot of time
sitting on the ground, while foraging or preparing food, then
long legs would get in the way. And long arms could be useful
for such work.
> . . . And the big problem remains: What did Lucy do
> with her child while she was foraging like this? It's a
> problem under any scenario, since (IMO at least) she could
> not have been carrying it on her belly. The only general
> solution I see is to propose a lot of shared infant-caring
> which also probably implies static sites.
If the static sites came first, while the proto-hominid was
quadrupedal, then it's not too difficult to see how shared
caring could emerge. If the site was quite safe and if the
food supply was local and nutritious, and if a group of
mothers and infants spent most of their time there, then
those mothers that began to leave their (initially older)
infants while going on brief foraging trips would tend to
do better. A pattern of mothers taking turns to forage
on their own could soon emerge. (In my scenario, btw, any
infants taken foraging would often get wet; something that
would not do them any good.)
Once free of the "lump" mothers could begin to stand and
walk upright.
During this phase, of course, we are concerned only with
the cross-over population. So it would be very small and
there would be no pressure on resources. That would only
arise once full bipedalism and all the other adaptations
to the new environment had occured.
. . . . just talking to myself.
Paul.
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