Re: Human Language.

Thomas Clarke (clarke@acme.ucf.edu)
20 Dec 1996 14:43:37 GMT

In article <59csaa$318@news.indigo.ie> pcrowley@indigo.ie (Peter Crowley) writes:
>clarke@acme.ist.ucf.edu (Thomas Clarke) wrote:

>>> Can we ... then ask the
>>> question "what evolutionary circumstances led to the
>>> development of language by Homo sapiens?"

>> . . , the first circumstance was whatever favored bipedalism.

>Surely this is a typo, Tom. Bipedalism may have eventually
>lead to the right circumstances for language, but it *need*
>not have done so; and A.ramidus did not talk.

No typo. But perhaps I need to clarify.
Yes, other bipedal or nearly bidpedal species did not get language.
However, no non-bipedal species has ever gotten language
(unless we find that dolphins have language or something).
>From the very poor sample, I conclude that only bipedal animals
develop language. It is of course not inevitable.
Not all land animals developed flight either, but no sea
animal every developed flight (flying fish glide).

>>Calvin then discusses evolutionary pressure for the increase in
>>brain size in the motor skill of throwing.

>Many birds, bats and monkeys throw themselves around with
>superb motor skill; fish in the Amazon aim droplets at
>flies. Such motor skills need minimal brains. Chimps are
>not too bad at throwing. And there is no evidence for any
>throwing before about 50 kya.

Calvin's ideas are no dobut controversial. He is a neurophysiologist
by training. I don't take the fish as counterexamples, their
skill is a hardwired specialty. It is like saying that human
inventiveness is just the same thing as a bouwer bird.
Chimps are somewhat along the way to human ballistic skill, no doubt.
Calvin calculates thate the critical thing about throwing accurately
is the release time. Since neurons are inherently noisy devices
the only way to obtain better timing and hence more accuracy (short
of some hardwired solution) is to average a lot of neurons so that
the noise or timing jitter cancels out. Hence, more brain (no other
changes) gives greater accuracy means more hunting success means
more offspring etc.
I think the idea has some plausibility.
Oh, Calvin even argues that the best interpretation of what was
done with the Archulean (sp?) hand "axe" was that it was
used as a throwing weapon as well as for pounding.

>>More brain = more neurons
>>to control rock release giving better timing giving better hunting
>>success giving evolutionary advantage. Result Homo erectus.

>Hunting is most unlikely at this time. The A-piths
>certainly did not have the anatomy for it; neither IMHO did
>H.erectus.

Before I start, all of Calvin's books are on-line:
http://weber.u.washington.edu/wcalvin

Calvin's scenario has A.piths approaching a water hole where
a number of animals are drinking. Then at a distance throwing/lobing
a rock into the crowd. With luck - often enough to drive evolution -
one of the animals is knocked senseless and its A.pith feast time.
This would probably only work with smallish animals.

>>When the ice ages kick in, Calvin finds evolutionary pressure on the
>>fringe populations that live at the edge of the advancing ice sheets.

>Ice ages have been the norm for the past 20 million years or
>so. Nothing kicked in. Anyway surely it was all in
>Africa?

Norm? hardly. I can't make out your geographic location from
you address but if you are very far north your home would have
been under ice 20,000 years ago. Yes before 20MYA there were
no ice ages, the started occuring episodically and a particulary
intense episode kicked in around 1MYA and is still on-going probably.
I guess we can have a thread about whether the climate of the
past million years was special.

>>These small populations evolve rapidly to adapt to the harsh conditions,
>>and then when the ice retreats it is these "hardy" populations that
>>expand to fill the new ice free land. When the ice advances again
>>the now much larger evolved population of "hardy" types pushes south
>>displacing older populations. This process repeats many times during
>>the pliocene eventually resulting in Homo sapiens. (Neanderthals along
>>the way, probably).

>This is the appalling "evolution forces" argument. We are
>talking about tens of thousands of generations, while these
>climatic changes are happening. You don't go south just
>because there is a secular trend towards a fraction of a
>degree colder since your grandfather's time. Random changes
>over a few years or decades would completely swamp out the
>effects of such trends.

Recent climatological research shows that the switch can happen
quite rapidly when the course of, for example, the Gulf Stream
in the North Atlantic changes, removing a major source of heat
from Northern Europe.
Thus the time scale is more like 100s of generations at most.
Also, I don't see how the evolutionary argument is much affected
by the time scale. A time 0 say you have populations in
areas A and B. Times passes. Area A is uninhabitable, so
the population (reduced?) is now squeezed into B.
Did the genes in area A vanish? No, given any sort of population
diffusion the population now limited to A will have a mix of
the genes from A and B.

>Populations do NOT migrate in response to climatic change.
>They fade away. Take a look at your local fauna. Why
>does this absurd error come up again and again and again?

We are talking about human beings. Not polar bears.
A human being takes off his furs and heads south, fighting
those occupying the land if necessary. If the glacier reduces
your hunting range, aren't you going to extend your range
further south? If your neighbor to the south objects, the
the better man will win.

>It also depends entirely on the "hunting hypothesis". How
>else could these hominids have survived the winter? Did
>they have fire and shelter? When are you talking about?

Sorry, if that wasn't clear. In the ice age times it is
H. erectus in question and H. erectus has fire and hunted
etc.

>>Donald calls this stage of mind the mythic stage. Language is
>>developed and becomes the dominant mode of social interaction -
>>imagine sitting around the campfire telling instructive "myths".
>>Mythic bipedal verbal craftsmen.

>Brains are vastly expensive. They did not evolve for the
>purposes of entertainment or a kind of "social glue"; that
>can be provided by a little elementary back-scratching.

Precisely the point. Calvin says they evolved for ballistic
hunting at first. For survival in the cold north later.
Then when they got big enough the possibility of tale telling
arose. Consider two tribal groups. One tells about hunting
trips around the fire, imparting skills to the young. The other
doesn't. Which has greater survival value?

>>With the Holocene cultural evolution with its complex feedback
>>loops (nod to Noel Dickover) and memes (Dawkins) eventually
>>results in the modern phase which Donald calls the theoretic
>>phase.

>The specific competitive benefits that come from these loops
>must be stated.

This has yet to be determined. In my youth there was great
question about the survival value of the behaviors resulting
from those loops. The world seemed to be on the brink of
nuclear destruction. Now not so much, but who know what evil
lurks in the heart of man.

>My own view, taken from Darwin, Keith, Goodall, and many
>others., is that warfare was the crucial factor. Success in
>war depends on skillful diplomacy, the making of alliances,
>inspirational leadership, technological and administrative
>superiority and many other skills, all of which need
>language.

OK. I buy that. Warfare is one of the feedback loops.
What is the survival value of warfare. Will we make it to
3000 AD?

I would put it the other way, though. Language is necessary
for war. Of course once you have war, then language becomes
more necessary etc. The feedback loop. Like sexual selection,
what objective good is a peacock's tail? Other than for getting laid?
Actually as I think, war is just a part of culture and probably
it is many aspects of culture, ware included, that participate
in the feedback that makes modern man.

> We can take lessons from the 20th century and
>see how the characters of modern nations are reflected in
>their languages and how the French, Germans, British,
>Russians, Americans, etc., succeeded and failed - each in
>ways that demonstrated their strengths and weaknesses coming
>from their characters and histories.

A mystery to me is why these characters persist. Why is change
so slow when potentially cultural change can be so fast?
Why are the Irish still fighting? Why does the south still
want to secede? Bosnia? Hutu's and Tootsies?

> If that *kind* of
>history is extended back to the australopithecines

I don't think this can be done. A.piths probably didn't
have language and thus culture and thus that kind of history.
It is not genetic. Think of how the mongols invaded Russia,
but became Russian. E.G. Yeltsin clearly has a lot of mongol
genes but is culturally a Russian.

> AND all
>hominids are set in a location that encourages and enables a
>story of continuous warfare, whereby losing nations/tribes
>are effectlively eliminated, then we have the beginnings of
>an account of the "evolutionary circumstances that led to
>the development of language".

I don't buy warfare before language.

Tom Clarke