The straw man.
Elaine Morgan (Elaine@desco.demon.co.uk)
Wed, 11 Oct 1995 17:07:49 GMT
I've noted two new anti-AAT ploys. One is to rename it AAH or AAS. No
hassle. A rose by any other name...Personally I'll stick to AAT because
I@m used to it, but the other terms are equally accurate. Like any
other attempt to explain the differences between apes and humans, it is
of course a hypothesis. It is of course a speculation. Renaming it is
an attempt at philosophical pseudo-speciation, implying "What you are
doing is qualitatively quite different from what we are doing." That
is not the case.
The other is the charge that AAT constructs a "straw man" in the shape
of the late savannah theory and attacks it because it is easier to
demolish than the more solid and unassailable scenario which has
replaced it. Rubbish.
AAT's case against the savannah theory as presented in the 50's and
60's was not that it did not accurately represent the ecologoical
conditiond in Africa at the timr of the split. We now know that it was
in fact inaccurate but neither side knew it then. The argument was that
even if it was accurate, it failed to explain the main physiological
differences between apes and humans i.e. it cannot be predicted that an
ape moving to the grasslands would become naked and bipe=dal.
Now look at the new improved model. Nobody questions it is solider and
more unassailable as a true picture of the the then environment. The
question is whether it is less or more successful at explaining our
physiology. The "straw man" gibe implies it is so much more successful
that AAT cringes from the prospect of challenging it and scuttles back
to the easier practice of attacking the late lamented savannah theory.
That is the reverse of the truth. Savannah Mosaic is not more but less
successful at explaining anything, The old ST claimed the hominids
became different because they moved to a radically and dramatically
different environment. It turned out not to be true, but at least it
sounded highly plausible.
Now the theory is that hominids diverged through living in an
environment that was only marginally different from other anthropoids.
They were still arboreal for part of, or most of, the time. No reason
has been suggested why they would not have continued to interbreed with
other arboreal offspring of the last common ancestor.
There has been no overt recognition that any of the explanations
offered by the old savannah theory have been weakened or need to be
abandoned or replaced. Wheeler's noonday ape theory continues to be
trotted out for lack of anything newer or better, as an explanation of
bipedalism although its raison d'etre has been fatally undermined. The
new scenario, even as presented by Wheeler himself, assumes th first
hominids not merely might have, but actually, did retire to the shade
for a mid-day siesta.
The supposedly unassailable new model theory offers exactly the same
explanations as the old one - nothing new at all - but it attributes
them to the necessity of occasionally crossing the open spaces between
one patch of forest and the next. It apparently assumes that one
subsection of the l.c.a. made a habit of crossing the open glades
while the others stayed at home; and that they remained from the
beginning genetically isolated from the tree-dwellers they left behind
and the other tree-dwellers they encountered in the next patch of
forest. It assumes that these excursions turned them into naked bipeds.
If it was hard to believe that a life of obligatorily scavenging a
meagre living on the the savannah on a full-time basis would do that,
it is very much harder to believe that life in savannah mosaic would do
it. AAT has no need to attack obsolete straw men when the latest
version is even more insubstantial, in terms of its explanatory power,
than its predecassor.