Re: Aquatic ape theory

Osmo Ronkanen (ronkanen@cc.Helsinki.FI)
17 Oct 1995 20:06:56 +0200

In article <45sdmd$>,
Tom Clarke <> wrote:
>ronkanen@cc.Helsinki.FI (Osmo Ronkanen) writes:
>>In article <>,
>>What my point is that whether a human being has hair is hardly
>>irrelevant for the survival. That means it is either beneficial or
>>harmful. If the hair is beneficial, then I see no reason why human
>>beings should not have developed the hair back in the millions of years
>>since the aquatic life. That strongly implies that the lack oaf hair is
>>beneficial in the land life. If it is beneficial one needs no aquatic
>If I may jump in, I understand your point, but here is why I think
>it does not eliminate the near for an aquatic interlude (or in general
>isolation in a very special environment).


With isolation I agree, but I see no reason it has to be aquatic.

>The hominid package: bipedalism and nakedness works. The Australopithecines
>survived for millions of years with brains not much bigger than apes.
>All the various reasons relating to heat rejection, carrying, tool use,
>enabled the hominids to occupy the diurnal ominvore niche (I forget
>who suggested that, thanks).
>The problem is to get from hairy quadrapedalism to naked bipelism.

There is no reason to assume that the changes happened at the same time.
There may have been millions of years of hairy bipedalism in between.

>The route for the change must be positively adaptive at every step.
>Hairy bipedalism has heat rejection problems.

How so? If the animal was not a meat eater, of it did not run and if it
had small brains and if it was generally small, it did not need so good
way of getting rid of heat. The upright position developed 4-5 million
years ago. Maybe the body hair was removed only with Homo Habilis 2.5
million years ago.

> Naked quadrapedalism
>has heat input problems and cold night problems.
>How could these two changes happen in a "coordinated" fashion to
>result in the successful hominid package?
>I think the answer is that a group of Miocene apes was isolated in
>an environment that favored both hairlessness and bipedalism and
>also favored hairlessness alone and bipedalism alone.
>The only such environment I can think of is the seashore.
>I am open to suggestions, though.

That is speculation. You seem to start from assumption that there was an
AA and then find all kinds of circumstantial evidence to support it.

>Tom Clarke