High diversity of Amerindian languages

[Arame]

The extremly high diversity of indigenous American languages is quite perplexing for me.
http://en.wikipedia.org/wiki/Indigen...f_the_Americas

We know that indigenous Americans didn't have high genetic diversity. the first humans entere there before 10000 BC and the majority of them where Q-M3 haplogroup. Also some C3b and perhaps R1b. So at the starting point they had 2-3 languages then later we should expect the same number of language families.

But the end result is very different. More than 100 language families (!!! not groups). Only in California there was more than dozen of language families.

How this can happen?

I think the reason is that when those people entered America they didn't have mature and stable languages. They have perhaps some basic vocabulary ( less than 50 words ) but not fully developed language. The human languages appear after 10000 BC so in Indigenous America we see the first burst of this creation process.

Perhaps this may be aplied for languages in Old World too.

[LeBrok]

One hypothesis about when people started speaking languages, says that this ability coincides with growth of Trigeminal Nerve. This nerve is responsible for sensing and controlling mouth and tongue. Human Trigeminal nerve is much bigger than in our primate cousins. If this nerve had exactly same funcion in all primates, humans included, it should be the same size in all primates, but it is not. We know that in humans this never also play motor function to contral mouth and tong during talking. Talk is complicated phenomenon therefore Trigeminl nerve is more robust in humans, to fulfill this extra function, than in other mammals who don't talk. If we could compare the size of this nerve to other hominids who used to walk the planet, we could determine when people started to use talking for communication, therefore beginning of languages.

Nerves don't last too long after death, so we can't analyze them from archaeological point of view. However there is a little trick, which can help us. This Trigeminal nerve, starts in a mouth and in order to rich brain, has to come through the skull, through the bone. In a place where it happens there is a little hole in a skull, called Foramen Rotundum. In Humans this Foramen Rotundum is much larger than in other primates, therefore corresponds to the size of nerves responsible for motors skill of a mouth.
Now when we look at ancient skulls of hominids, and compare the size of Foramen Rotundum, we could determine when it got bigger and people started to talk. Definitely Neanderthals have big Foramen Rotundum, and should have been able to talk. Home Sapience definitely talks since beginning of our species, with vast vocabulary and most likely complicated grammar. Talking probably started during times of Homo Erectus, when our brain enlarged dramatically.

http://en.wikipedia.org/wiki/Trigeminal_nerve

[Arame]

Thanx LeBrok.
Well I don't say that people were not able to speak at Paleolithic. They had a some sort of language. I believe Neandtharls also were able to generate some words. I am not speaking the mechanic part of the speach. Like muscles, nerves. Building the mechanical part is not the hardest part for Nature IMHO. The hardest part is the software that controls all this mechanics.

So my assumption is that languages were rather rudimentary 12000-15000 years ago. They were not stable, they were not developed. To stabilise the language You need social structure who keep the language. For examples priests and other notorious persons.
Also the number of vocabulary is important. If the initial colonisers of America had a rich vocabulary we should expect to find the more or less same worlds all over the Americas. But it is not the case as far I see.

[Alan]

A simple explanation is the tribal structure among Amerindians. The more tribe orientated (the more tribes exist), the more the dialects will diverge from each other. And when think about a 10000 years of time... That is self explaining.

[Aberdeen]

I don't think it's possible to explain the linquistic diversity of Native North American languages. Genetics and archeology, when considered together, suggest that the Americas were originally peopled perhaps about 15,000 year ago by at most a few small bands of hunter gatherers from Asia who were not very genetically diverse. A second major wave, the Dene people, seem to have arrived 8000-10,000 years ago and the ancestors of the Inuit much more recently. And the Dene and Inuit language groups are easily identified, since they didn't diverge all that much. But the descendants of those original peoples somehow developed dozens of major language groups that don't appear to be related to one another. There are also hundreds of language isolates, not to mention those languages that may have disappeared before they could be recorded. Why did those original small bands of hunter gatherers develop such a diversity in somewhere between 50% more time to twice as much time as the Dene were here, when the Dene language group didn't diversify nearly as much? Although the very first Amerindians may have spoken a few different languages and they expanded over a much wider territory than the Dene or Inuit, I don't think that fully explains such huge diversity.