Re: Aquatic Ape: The Fossils Say No!
5121 Student 09 (cm315c09@nova.umd.edu)
1 May 1994 09:15:23 -0400
NICHOLLS PHILIP A <pn8886@thor.albany.edu> wrote:
>> Lucie Melahn (lmm5@cornell.edu)
>
>> People are getting into very heated battles over the evidence for
>> and against aquatic v. savannah apes. There is no point to this.
>[stuff deleted]
>Now since everyone admits the savannah was involved the issue is not
>aquatic vs savannah ape (or protohominid) but whether there is
>evidence for an aquatic phase.
>
>Morgan discusses a long list of physiological differences between
>apes and humans which she claims are "scars" of our aquatic
>ancestry. David listed many of these in a previous post. The major
>problem with this list is that there is really no reason to believe
>that all of those traits occurred at the same time (the 1 million
>year aquatic phase).
As a major problem, that's not too major.
>To put it into conventional evolutionary
>theory, Morgan assumes that these traits became fixed in the human
>phenotype as a result of an adaptation to aquatic life. Some of
>them, she claims, are the result of convergent evolution while others
>are unique adaptations (like bipedalism) that carried over into
>savannah life. In my opinion, Morgan has not made a convincing case
>for either convergence or an aquatic origin of bipedalism.
To hell with Morgan already. To hell with convergence already.
You sound like a broken record. These boring points have been
conceeded. They only show that Morgan was wrong on some points.
Big deal.
>Many of the traits are inconsistant with aquatic life. This includes
>hair loss and sweat glands.
Hair loss is not inconsistant with aquatic life.
Loss of sweat glands would require total aquatic life and no one is
claiming that.
>Some can be explained as the result of
>phylogenetic trends unrelated to early hominid evolution. This
>includes the shape of the nose which, as I tried to point out, is the
>result of the flat hominid face.
Which still begs the questions - why did the flat face evolve?
>As for bipedalism, it is important
>to consider the fact that apes do not as a rule spend much time in
>water
Nor, as a rule, do they spend much time walking upright on the
savannah. So what?!
>and even if they did there is no evidence that water would act
>to promote bipedalism.
There is no evidence, period! Nothing has promoted bipedalism
anywhere. So what?!
>The re-orientation of the pelvis and the
>changes in muscle distribution reflect weight-bearing. A aquatic ape
>would have most of its weight supported by water. That is why
>aquatic mammals tend to have thin pelvic bones.
Fully aquatic mammals, yes. No one is claiming that man is or
was fully aquatic.
>Now we know that primates do walk bipedally from time to time. Some
>are so well adapted to trees that when they are on the ground they
>cannot walk quadrupedally. Most of the hypotheses I have seen are
>based on known patterns of primate behavior or biomechanics.
And we know that several macaque and baboon species are excellent
swimmers and divers. These are known patterns of primate behavior.
Why are you ignoring them?
David Greene
cm315c09@nova.umd.edu
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