Re: EVOLUTION: The Aquatic Ape

Keith Henson (
Fri, 24 Jan 1997 11:07:58 -0800 (PST)

John, could you format replies with a lot less indent and use shorter
lines? My editor chokes on your postings. Thanks.

On Fri, 24 Jan 1997, John K Clark wrote:

> On Thu, 23 Jan 1997 Keith Henson <> Wrote:
>>I will certainly argue that a lot of animals humans hunted
>>were much larger than the strike zone!
> If the animals were much larger than that, then we can make 2 conclusions
> about these hunters who were armed with nothing but rocks and tiny brains:
> 1) They had a huge amount of courage.
> 2) They did not leave a huge number of descendants

The whole point of projectile hunting it to be able to damage your prey
at a standoff distance where they can't hurt you.

>>I very much doubt a hunting group got that many opportunities
>>to hit something in a day, certainly not as many throws as a
>>baseball pitcher will make.
> Even with great natural ability baseball pitchers need to practice to be good
> at their job, they practice constantly until their arm wares out. If these
> hunters saved their arm and did not practice, how could they hope to hit
> anything?

I know someone who could throw a very fast rock and hit small targets.
He did this on minimum practice. He was also very good with a sling.

>>So much context has been lost that I am not sure how this
>>ran, but I think my point was that bipetalism was a
>>prerequisite for throwing. My point was how the big expansion
>>grew out of the earlier adaptions to projectile hunting which
>>a chimp sized brain could support.
> Once bipedalism and a hand almost as good as ours was developed, the point
> Lucy was at, I don't find it all that mysterious that the brain grew very
> rapidly.

I don't think it did, i.e., brains stayed much the same for a million
years or more after Lucy (I think). There are some *real* problems in
growing larger brains, ask any woman who has had a baby. (Calvin goes
into these problems at length.)

Yes, it will help you with throwing, but with that good hand
> intelligence will help you do a lot of other things too. What I don't
> understand is why bipedalism developed and why Lucy evolved a first rate hand
> when she still had a third rate brain.

I don't have a pointer, but I remember that one chimp was taught to
chip rock--or at least fracture them to get a sharp edge. I suspect that
our hands are not that advanced over a chimp's.

> On Thu, 23 Jan 1997 (Jay Reynolds Freeman) Wrote:
> >even a prey species that would be very likely to lose in a
> >fight to the death with a predator, may be able to deter
> >that predator by virtue of the small chance of a different
> >outcome. After all, the predators aren't out for fights to
> >the death as such, all they want is lunch.
> I agree with that, I just have my doubts that a pre-human throwing a rock
> would even be a good bluff, and as a offensive hunting weapon I think it
> would be hopeless.

It might be more useful for that in the early stages, but after a while of
using rocks/sticks to fend off preditors, some genious of Lucy's clan
would use it to obtain lunch. After that . . . .

In fact, it has just occured to me that an animal who ventured out on the
flats, even to scavenge, would no longer have the option of going up a tree
to avoid preditors. If they already had a tendency to throw things (which
chimps do and Lucy most likely did) then they might very well take to
carrying sticks and rocks for preditor defense. The need to carry defensive
objects might well have been one of the things which led to bipedalism, i.e.,
those who knuckle walked and did *not* carry a big stick, got et. If you're
hungry for meat, and chimps certainly seem to be, venturing out on the plains
is a real temptation --because plains grow a lot of meat per square mile by
comparison to a forest.

Incidentally, isolation on the dryer side of the east african rift seems
to have been one major factor in the evolution of the human line.

Keith Henson