aat-reply to Moore.

Elaine Morgan (Elaine@desco.demon.co.uk)
Fri, 07 Jul 1995 16:31:26 GMT



James Thurber had a famous duelling cartoon in which one of
the swordsmen had sliced off the other one's head. The
caption was ;Touche! Okay, I was touche on the question of
whether AAT supporters argue that the hominids would have
been safer in water. I withdraw.

I liked your quote from my book that bp. evolved in
circumstances where it was "compulsory and at the same time
relatively free from unwelcome consequences" (such as falling
down, and varicose veins) I stand by that. It doesn't as you
imply give weightlessness as "a major reason" - obviously on
its own it would be no reason at all. - nor as "critically
important". The important thing was being able to breathe,
and would have operated regardless of any accruing benefits.

On this point. someone argued plausibly that as the water got
deeper it would have taken less energy to swim than to
wade.Well, yes. But in real life the proboscis does wade.
Possibly because primtes usually use a dog paddle and in a
mangrove swamp there would be roots and tangled vegetation
under the surface to catch in your arms and legs. It becomed
increasingly likely that a flooded forest rather than the
seashore first triggered aquatic behaviour. The more
frequently bipedal of the African apes (bonobo) lives in
seasoanlly flooded forest.

Dr Moore doesn't like my claim that b.p. was adopted under
duress. He says brachiators "virtually always use b.p. on the
ground". Which ones? African apes usually use knuckle
walking for locomotion, orange usually use fist-walking.
Gibbons in the wild never come to ground if they cabn help it
and when they do they walk bipedally under duress. They have
no option, because they are so hyper=specialised for
brachiation . If a dog was born with arms twice as long as
its legs, it would have to resort to bipedalism too. If you
use the gibbon as a model for opur bipedalism, you imply that
we were more intensively specialised for brachiation than
apes and gorillas. You don't really mean that, do you?

By the way I have never said these creatures walked up yo
thir nacks in water. That would be stupid. What you refer to
as my repeated use of the term "head-out immersion" had
nothing to do with hominids. It was in a very speialised
context, a standard term used by researchers in therapeutic
experiments with modern humans.

Re running on four legs:the reference was to Carrier (The
Energetic Paradox of Human Running and Hominid Evolution,
Current Ant. 25,4.) "Running humans expend approx twice as
much energy per unit mass as typical mammalian quadrupeds of
the same size....Unlike human running, human walking is as
least as economical as the walking of typical mammalian
quadrupeds.....In order to become an endurance runner man has
had to overcome the handicap imposed by a relatively high
energetic cost of transport.." The apparent contradiction
between this and your source is that the animals on the
treadmill were fast-walking and slow-walking. The human
running gait is an entirely different operation (Kimura et
al, 1983)

I know -and am sure D. Dennett knows - that many esteemed
scientists respond to the mention of AAT by rolling their
eyes. I have seen them jumping up and down and shouting. But
his question was not how do you feel about it, but please
tell me exactly why it must be wrong.

Too much of the counter-argument is ad hominem - Morgan makes
mistakes, she is not qualified. And now, if Dennett thinks
that an insufficient answer, there must be something wrong
with Dennett. And if Dawkins and Pinker and Wilson and
Diamond and Kitcher and Calvin can't see that, there must be
something wrong with them too.

There is an awful lot of probing into what might be wrong
with AAT, when all that is needed to wipe it off the face of
the earth is for a small group of real scientists to get
together and say: "We do not need it. We know exactly why
humans are naked and bipedal and have such untypical
respiratory arrangements. The explanation is as follows:"
...and that would do the trick. But as long as they say "We;
're still working on that" or "it is not that simple" or
"there are so many answers to that it would take too long to
expound them all" then AAT is not going to go away. And the
number of people who take it seriously, and thus put
themselves beyond the pale and uncur guilt by association,
is going to increase.

Elaine Morgan