Re: Aquatic Apes 3 of 5

loopy (lmm5@cornell.edu)
10 Dec 1994 23:26:24 GMT

In article <3c0ul8$cvd@newsbf01.news.aol.com>, patdooley@aol.com (Pat
Dooley) wrote:

> He misses the point that bipdalism is much less efficient for the other
> apes
> than their usual mode of locomotion. Conversely, most of us humans avoid
> knuckle walking.

We don't knuckle-walk because it is a very specialized form of locomotion,
just like bipedalism. If the first biped was an inefficient runner or
walker, then that provides evolutionary pressure for that hominid to become
a better runner or walker.

> How do we know the common ancestror of around 12 mya was not a knuckle
> walker. About all we do know for certain is that it wasn't truly bipedal.

strictly speaking we don't know either, since we haven't found fossils from
that period.

> to protect the face, shoulders and upper back from UV radiation. Severe
> sunburn
> and increased skin cancer rates are not a price that other savannah
> animals
> were willing to pay for the advantages of hairlessness.

you're assuming the hominids lived long enough to develop skin cancer.
*IF* they did get cancer, natural selection wouldn't weed it out as long as
the hominids had reproduced *first*. Selection acts on reproductive
fitness.

Lucie

-- 
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L.Melahn, lmm5@cornell.edu MYN GLAS LOOPT RAS
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