Re: A critique of the BBC aquatic ape programme and the transcript.


Algis Kuliukas wrote:


[snip]

> The question is this: Was Man's ancestors *more* aquatic than the
> ancestors of the apes since the LCA of both? Let's just stick to that
> for a moment. What's so vague about it? If it was "Were the ancestors
> of the Apes *more* arboreal than the Man's ancestors since the LCA of
> both?" would that be as problematic for you? Why? or Why not?

In this question you reveal your limits and your contradictions. Dare
I say you reveal your own double standard. We can look at present day
chimps and see that they are more arboreal than humans, that
by-and-large some degree of life in the trees is present in virtually
all chimps. It's part of the present day niche of their species that
isn't part of the niche of all humans. This doesn't parallel swimming
as swimming isn't part of the niche of all humanity. It's one of the
many environments we can and do exploit, but hardly is it necessary or
characteristic of the species as a whole. In this regard, your analogy
is rather limited.

But even this really is besides the point. You are confusing the
general: "are apes more arboreal" with the specific of particular
traits that make them more arboreal. Sure. A chimp is more arboreal.
That's a boring "hypothesis" though that is trivial when addressing
functional anatomy and not at all helpful in this regard. It's
problematic if you're interested in functional anatomy and so if you
started with this question in hopes of addressing funtional anatomy
from it, I'd say it's hardly a hypothesis of interest and not worth
taking time with. It's as boringly useless as being "more aquatic."
They were more arboreal. BFD. Does this mean that any difference
between the two is a result of that? I suspect that in honesty, you
have to say that it does not. Deep six the arboreal umbrella. Not
worth wasting time on and proceed ot the actual features and ask
particular questions about how they function. We *can* look at
particular traits in chimps and see *if* they are related to an
arboreal lifestyle (or remnants of one in the past) but we do so by
looking at the trait, how it is used *and* what other creatures seem to
have similar adaptations. For instance, chimps have curved finger
bones. This appears to be part of an adaptation for life in the trees
because it shows up in a number of arboreal primates and doesn't seem
to exist in the same fashion in more terrestrial species. While
nothing in science is ever dead-set certain, there's justification for
a reasonable hypothesis that the trait is related to arboreality. [Of
course, it was very likely also present in ancestor species of chimps,
so its presence in chimps isn't necessarily an indication of selection
*for* it in chimps, but rather retention of the trait.] But in a
large enough sample size we can see that form and fuction appear
related and this confirms (it does not prove but confirms) that the
form has provided a selective advantage for the particular function at
some point. Without this we wouldn't be able to say if the trait
followed selection or not even if it appeared to help them out in the
trees.

And herein rests where your methodology breaks down. If you want to
look at hairlessness as an aquatic trait and claim that the unique
appearance in humans is the result of selection, you've got to find a
way of establishing that it is an aquatic trait and not caused by
something else. This can't be done by measuring human variation and
apes only because it doesn't distinguish between cause and effect of
another cause. The answers from shaved humans relate to selection only
after you've assumed that selection *on this trait* occured as you
suppose it did. Unlike the particular arboreal trait above where we
can see it functioning in other arboreal creatures, you've got nothing
to establish that hairlessness is an aquatic adaptation in humans and
don't seem to want to look at how hairlessness appears in other
creatures or what sort of environments actually produce hairlessness on
what sorts of creatures.

And there ARE traits that seem to serve a purpose that didn't arise
because of that purpose. The great mobility that we have in our
shoulder is a prerequisite for the type of swimming we do as it is a
prereq for throwing things, both behaviors that I've heard here as
explanations for how we diverged from apes. But the basic makeup of
this shoulder isn't a product of swimming or of throwing. It's a trait
that we share by-and-large with other apes due to a brachiating common
ancestor. The adaptation was for brachiating, though it also later
allowed for other unrelated things. And seeing a similar structure in
New World brachiators but no other creatures we can be reasonably
certain that it was an adaptation for brachiation. This HAS been
studied and it's been studied using the comparative method, we
researched and written up (A. L. Jones. The Evolution of Brachiation in
Atelines: A Phylogenetic Comparative Study. 2004. PhD dissertation. UC
Davis.) and because of it, we know more about how the suite of traits
relating to brachiation function. Comparative functional anatomy. Real
stuff, not the AAX bastardization of it that's been presented here.

But you eschew this methodology for some bizarre reason and replace it
with your own wholly insufficient one. Your methodology provides no
answers. It remains a circular argument that doesn't address cause,
though your umbrella "hypothesis" wants to address cause. This is a
disconnect and makes the umbrella useless the subhypotheses. If you
don't get any answers other than the ones you started with, why the
hell are you bothering with the question in the first place? If you
want to study something, do try to study it in a way that when you're
done, you'll know more about the question you initially asked that you
did at the beginning. As you're outlining it, this will not be the
case.

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