Re: AAT Theory

Alex Duncan (
28 Sep 1995 01:59:36 GMT

In article <> Paul Crowley, writes:

>"Explanation" is the key word, Chris, and I'm still waiting to see even
>the beginnings of an attempt at a non-AAT one. Parsimony only matters
>between two or more explanations. So far there's only one.

If you are unaware of other explanations, then my working assumption must
be that you've never actually read anything in the paleoanthropological
literature. You should strap a sign to your back that says "ignorant."

>The AAT critics are not focusing hard enough on the problem that needs
>explaining. This is understandable in historical terms - because it's
>traditional to ignore it. But it's a big one and it's not going away.
>The initial stages of bipedalism are hellishly difficult to explain.
>We now have all sorts of adaptions that make it easier. The first
>hominids didn't. They were doing it with short legs, wrong musculature,
>a weak spine, ill-adapted feet, etc. It's as though we decided to go
>around on our hands and knees. They must have had *compelling* reasons.

I'm very disturbed that someone with your apparent lack of information
would choose to discuss such matters on the net. What exactly do you
mean by "wrong musculature, a weak spine, ill-adapted feet." How do you
know that the feet of australopithecines weren't perfectly adapted to
what they were doing? Your assumptions are baseless.

>The problem has a hundred aspects; for example, consider the babies.
>Baby apes can hang on to mother while she forages. Soon they can safely
>clamber around the trees. Early hominid infants, with only two weak
>grasping limbs, couldn't hold on; so the mothers had to use an arm to
>carry them (or put them down) while foraging. And then the infants had
>to learn to walk upright (with their short legs, wrong musculature,
>weak spines, ill-adapted feet, etc.) Get the scene?

How do you know early hominid infants couldn't hang on? The earliest
good evidence for altricial infants is H. erectus. Previous to that, we
have no reason to assume hominid infants couldn't hang on just as well as
baby chimps.

>Now put these creatures on the ground in lion-infested territory and ask
>"How did they get through twelve dark hours every night?". Trees have
>got to be ruled out, or they'd be straight back to four grasping limbs
>(saying: "Phew! - who came up with that real bad idea?").

Once again, I'm nearly struck dumb by the depth of your ignorance.
Please, please read some of the paleoanthropological literature before
you post this kind of garbage. It actually hurts me to read it.

Alex Duncan
Dept. of Anthropology
University of Texas at Austin
Austin, TX 78712-1086