Re: EVOLUTION: The Aquatic Ape

Keith Henson (keith@filoli.com)
Thu, 23 Jan 1997 11:04:53 -0800 (PST)


On Wed, 22 Jan 1997, John K Clark wrote:

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> On Tue, 21 Jan 1997 Keith Henson <keith@filoli.com> Wrote:
>
> >I can't recommend enough that you *read* Calvin's work
> >before arguing this topic.
>
>
> I did read Calvin's "The Throwing Madonna" a few years ago, I have not read
> his "The Cerebral Code", except for a few pages I thumbed through in a
> bookstore. The trouble I have with his idea is that throwing an object with
> power and accuracy is the most complex, difficult, motion you can put your
> arm through,

It may not be, but it is likely to be the motion most connected to your
genetic survival. And, as Calvin points out, it takes a hell of a lot of
neurons to get the release timing down to the point you can hit targets.
The basic problem is that the timing jitter of nerve cells is way to
high, so high that when Calvin first started thinking about the problem,
he could not figure out how we could hit *anything*.

it's hard to believe that it's also the first motion an arm
was
> used for when it was no longer needed for locomotion, even modern humans are
> not very good at it. Baseball pitchers get paid millions of dollars because
> they have more natural ability at throwing things than 99.9% of the
> population, and they still miss the strike zone about as often as they hit it,
> and that's a lot bigger than most animals you would hunt, and it's not moving,
> and you're using aerodynamic baseballs not irregular rocks, and your brain is
> almost 5 times as big as Lucy's. Also, throwing hard creates a huge amount of
> ware and tare on the arm, after a few years of doing it for a living the arm
> is not of much use for anything, ask any old retired baseball pitcher, an old
> man of about 35.

I will certainly argue that a lot of animals humans hunted were much
larger than the strike zone! They also hunted in groups, where any one
of them getting in a good one was enough. And while living to 35 was
likely plenty to pass on genes, 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.

> >it seems that pre humans got along just fine as projectile
> >hunters using hand axes thrown discus style into groups of
> >animals at water holes/streams for millions of years.
>
> This might be true but could have nothing to do with the development of >
bipedalism. Lucy was as bipedal as you or me but it would be a million years
> later before anybody on earth had a hand ax or a tool.

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 adaptionsaddaptions to projectile
hunting which a chimp sized brain could support.

> >In such an environment, really good projectile throwing made
> >the difference between a line which left a lot of descendants
> >and one which left none. Calvin argues (very well I think)
> >that this is what drove the expansion of the human brain
>
>
> It seems to me that if Evolution was only interested in solving one
> particular problem, rather than problems in general, it would have developed
> an elaborate throwing reflex, not intelligence. Then again, Evolution never
> does things the easy sensible way, so maybe.

Calvin argues that the expansion of the brain for throwing hauled along
many, many other things. The same motion sequencer that is used to throw
rocks he proposes gets used when not throwing for such things as
generating sentences.