Re: AAT: Req for alternative
Elaine Morgan (firstname.lastname@example.org)
Wed, 3 Jul 1996 16:53:25 GMT
Hi Dewi. Good question.
I don't believe there has been any new thinking since the savanna-based
scenario changed to a mosaic- based one.
The reactions have been not to seek a new paradigm but (a) to minimise
the differences between homo and the other apes (we are not really much
nakeder, not really any fatter, not really much more more erect, etc.)
(b) to suggest it is futile to look for reasons (they didn't say this
when they thought they knew them} because there may not be any or we may
never find them (c) to suggest (without hard evidence either way) that
most of the distinctively human characteristics did not emerge until
millions of years later when there really was a savanna. Only nobody can
say this about bipedalism because the fossils prove otherwise.
The fourth kind of response is the mosaic hypothesis. If you want an
alternative paradigm, this is the only one in the market so far. It
most of the old reasons, like overheating or food-sharing, which were
formerly attributed to moving on to the savanna, will still work if you
attribute them to the time spent moving across grassy patches from one
patch of forest to the next. If fails because it does not explain why
a group which crossed such an open space would not immediatly interbreed
with the co-specific animals in the next patch of forest they came to.
If they did, there is no way that species is going to split into a
arboreal group and a grass-dwelling group. It also looks dodgy because
the kind of habitat it envisages is precisely that presently occupied by
the Gombe chimps, and they don't show any tendency to walk bipedally
more often on the grass than in the trees,(on the contrary) nor any
tendency to become more hairless,. nor to get overheated because they
are not hairless. .