Re: AAT is dogma

Nicholas Rosen (ndr102@psuvm.psu.edu)
Thu, 10 Aug 1995 11:36:49 EDT

In article <4091cv$ihr@geraldo.cc.utexas.edu>, alex duncan
<aduncan@mail.utexas.edu> says:
>
>And so, a question for proponents of the AAT: what would it take to
>falsify your hypothesis?

A legitimate question, to which I'll give an answer a little further
down. First, I'd like to observe that, barring a time machine,
general explanatory hypotheses in paleoanthropolgy are not easy to
falsify totally. Did australopithecus africanus get most of its
meat by hunting or scavenging? The observation that certain bones
show the marks of stone tools over carnivore tooth marks argues
for scavenging, but it is possible to patch up the Mighty Hunter
hypothesis by saying that the bones like that which happen to have
been found are exceptional, or that the human body shows
physiological adaptations to cursorial hunting, or that the fact that
many humans, especially males, like to hunt while few scavenge other
predators' kills for recreation shows that we evolved as hunters,
since animals evolve instincts to want to do what they need to do
for a living, etc.

Now, what exactly is meant by the Aquatic Ape Hypothesis? Did any
human ancestor ever get his or her feet wet? Sure. Did our
ancestors at any stage do enough swimming to have a major effect
on their physiology, accounting for hair loss, subcutaneous fat,
partially webbed fingers, upright posture, etc.? Maybe so, or
maybe, as most anthropologists believe, these phenomena have other
causes. Most specifically, were these characteristics acquired on
Danakil Island circa 5 my ago?

The Danakil/aquatic hypothesis seems potentially vulnerable to a
black eye or two, if not to absolute falsification. Suppose that a
human ancestor postdating the alleged aquatic interlude were shown
to be as hairy as a chimpanzee. Suppose that skeletons of australo-
pithecus ramidus or something very similar were found elsewhere than
at Danakil, and definitively dated to the the time when Danakil was
an island. These would go along way toward falsifying the Danakil/
aquatic hypothesis.

On the other hand, if australopithecine fossils were found in the
Danakil Alps, and dated to the interval when the region was an island,
and no other fossils dating to that period were found elsewhere, the
hypothesis would be strengthened, although not absolutely proven. In
short, the Danakil/aquatic hypothesis seems at least as open to
testing as its rivals, and I think it deserves investigation. I am
aware that hair doesn't usually leave fossil traces, but something
might happen, as it did in the case of the Iceman.

Nicholas Rosen
Standard disclaimers apply.
Also the special disclaimer that I am not an anthropologist.