Re: Indo-European question

> a) "Within a few generations" is most certainly not "overnight".
In biological terms, it is. Assuming 20 years to a generation, and a
possible timescale of, say, 100,000 years, then "a few generations"
(let's say 5) equates to 0.1% of the timescale.

Personally, I lean towards the view that modern humans have been
around for at least 500k years, and possibly more than 1m years
(0.01-0.02%).

> b) Human children are "predisposed" to learn language. This must, I'm led to
> believe, mean that somewhere in the human genome there's something which
> makes us acquire langauge during childhood. A such genetic adaption could,
> in theory, indeed arise overnight (due to a mutation), but it wouldn't have
> much effect until a reasonable porportion of the population had it. More
> probably, this genetic mechanism consists of several mutations that occured
> at different times and each one had an more or less immediate advantage for
> the individual - that's how genetic adaptions usually work. Exactly where
> along the line of development the acoustic communication became "langauge"
> is, I guess, mostly a question of terminology (perhaps when the
> phoneme-morpheme system was into place?).
>
That children have an innate ability to acquire language, and this
ability is largely lost after the first dozen years or so, is accepted
fact. The question is: where does this ability come from?

I would argue that the purpose of the juvenile phase of any mammal's
development is to acquire enough information to allow the mammal to
survive and thrive in its environment. The brain is the organ used for
this purpose, and it is arguable that much of the information gathered
and stored is through a mechanism of pattern matching and cross
referencing. This juvenile phase ends with the onset of sexual
maturation, when other skills become more important.

Now, there is an argument that a unique, defining difference between
humans and apes is that humans delay the onset of sexual maturation by
a significant period. This also increases the period allowed for
information and skills gathering, and social development.

Evolutionary development is not only about the rate of genetic
mutation and survival of the fittest. It is also about using existing
skills and abilities in novel ways to gain an advantage over competing
species in a given ecological niche.

And when genetic mutation is involved in a small, geographically
discrete population, the effects of the mutation can spread through
the population in a handful (3-4) of generations - spectacularly
quick.

So, what if - rather than recieving a magical gift, or a fortunate
genetic mutation - humans were able to put an existing skill
(information gathering, pattern matching and cross referencing in the
brain) to a new use, such as the development of a sophisticated
communication system. What if delaying sexual maturation allowed this
to happen quickly?

Certainly, understanding and using human language is a complex skill
relying on whole reams of biological and neural systems. But delaying
the onset of sexual maturation is a simple thing, principly delaying
the release of the sex hormones testosterone, oestrogen, progesterone
(and a few others) into the blood stream at the appropriate time. This
(I believe) can be achieved through a small number of genetic
mutations. And the change could be significant, for instance
increasing the juvenile period from 2-3 years to 10-12 years at a
stroke.

This change would allow language skills to develop over the course of
a few generations. Then natural selection can swing into force: a
group of hominids capable of communicating and interacting effectively
will survive longer and breed more effectively than similar hominids
without this skill.

And this could happen time after time in separate lineages. A mutation
that alters the vocal tract in some way to allow that hominid to be a
better mimic (thus possibly a better hunter) could easily have
happened 1-6 million years ago, and would quickly offer an
evolutionary advantage. A genetic change in the neural network to
accommodate better aural pattern matching and cross referencing could
have extended a simple aural communication system from a dozen sounds
to a couple of hundred sounds. Then a genetic change to delay the
onset of puberty, thus allowing existing information gathering,
pattern matching and cross referencing skills to be put to a new use -
the development of a complex language - could have led to a cascade
effect of rapid evolutionary development and an exponential
(or greater) explosion in numbers of the lucky population(s) where it
happened.

In effect, language maketh man.

I'm not saying this is the way it happened. I'm just offering a
hypothesis of how it could have happened. And at least this hypothesis
can be tested and challenged, through the study of evolution in other
species, and developments in the ever-burgeoning fields of brain and
cognitive studies, etc.

>                                                        Andreas
Rik, knee deep.

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