Re: Bipedalism and endurance (was Re: AAH - enough already
Phil Nicholls (pn8886@csc.albany.edu)
17 Dec 1994 04:41:45 GMT
In article <5A3UmlU.patdooley@delphi.com>,
Pat Dooley <patdooley@delphi.com> wrote:
>loopy <lmm5@cornell.edu> writes:
>
>>In article <3c10e0$dak@newsbf01.news.aol.com>, patdooley@aol.com (Pat
>>Dooley) wrote:
>>
>>> Whatever you said hardly applies to Lucy and her predecessors. Big feet.
>>> Short legs. Not very big to start with. More like Toulouse Lautrec than
>>> your favorite track star.
>>
>>sort of like asking, what good is 10% of an eye? the answer is, 10% of an
>>eye is better than no eye. Evolution doesn't start out by producing perfect
>>systems.
>
>Nor does evolution produce disadvantageous intermediates. Read Dawkins
>for more information on the process. The problem with the idea that
>bipedalism evolved as Hominids moved from the forest to the savannah
>is that there is no opportunity for the new feature to evolve. An
>ape adapted for an arboreal life is going to be easy prey if it starts
>tottering around bipedally. It's not like going from 10% of an eye to
>100% - it's like giving up adequate eyes and evolving a new methos of
>vision. The blind creature at the half-way point of the transition
>could not exist, no matter how good the final result. Similar
>principles apply in designing computer programs in chess: there is
>no point in searching from a great board position three possible
>moves ahead if you have to rely on your opponent making a stupid move
>to get there.
Creationists over on talk.origins use this exact same logic to argue
that evolution is impossible. Since most primates engage in occasional
bipedal locomotion the behavior is obviously not disadvantageous and
while they may not be as efficient as humans they only have to be more
efficient that quadrupeds or AS efficient with some additional advantage
being acquired as a biped that you don't get as a quadruped. I have
already (SEVERAL TIMES) mentioned studies that show that walking on
the ground bipedally for chimpanzees is about as efficent as walking
quadrupedally.
Evolution doesn't design perfect systems from scratch. It uses
existing behaviors and morphology and modifies them.
--
Philip "Chris" Nicholls Department of Anthropology
Institute for Hydrohominoid Studies SUNY Albany
University of Ediacara pn8886@cnsunix.albany.edu
"Semper Alouatta"
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