Re: AAT Theory
Paul Crowley (Paul@crowleyp.demon.co.uk)
Tue, 26 Sep 95 20:09:54 GMT
In article <44923f$hmn@geraldo.cc.utexas.edu>
gator@mail.utexas.edu "chris brochu" writes:
> parsimonious explanation for our evolution is still not the AAT, with or
> without it. That's how parsimony works - you take all available evidence
> and select the explanation that best fits all of it.
^^^^^^^^^^
> Some postings on this subject seem to suggest a thought process like,
> "well, your idea may explain facts A through Y, but since my idea
> explains Z better, mine must be correct." That's not parsimony. That's
> special pleading.
"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.
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.
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?
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?").
Still waiting to see a non-AAT explanation . . .
^^^^^^^^^^^
Paul.
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