No Language Facility Evolution Since 100kya

In other words, the evolution of our language ability was effectively COMPLETE by one hundred thousand years ago.

I’ve been shocked in the last year or so to see it claimed on TV, that language started evolving fifty thousand years ago. Both Stephen “in 50,000 years – we went from grunts and squawks to TS Eliot” Fry and Michael Wood, in “The Story Of India” allowed that to get out. In both programmes an Indian academic suggested language may have evolved in India at that time.

One slight problem with that idea is that genetic flow has been largely out of Africa, and prior to 1,000 years ago there was very little genetic invasion of any kind into southern Africa from outside Africa. Yet people there had language.

In recent years we’ve discovered that amongst human groups surviving today, the oldest to split away from everyone else were the San people, once known as the Hottentots or bushmen. In any case, even prior to modern genetic investigations, they’d always been guessed to be the earliest offshoot. The date most recently estimated? 130,000ya [see ref below]. Perhaps that date might be using an innaccurate clock and should be just under 100,000. If you use the clock New Scientists thinks we should be using, the date would be nearer 200,000. But anyway, if language evolved 50,000ya but people in that offshoot have the same language facility as everyone else (and Chomsky said in the MIT +150 conference in 2010 that all peoples do have as far as we can tell, exactly the same inbuilt language facility), then either that offshoot split off but then miraculously evolved exactly the same language facility as everyone else, or somehow the genes must have filtered back into Africa from outside and suddenly spread to the San. And not just to the San, because most other people in Africa would be in the same position, as the invasion into Asia and Europe is reckoned at about 70,000ya.

To cut a not very long story as short as it needs to be, the only possible realistic explanation for the pattern of language facilty and genetic influence is that language STOPPED evolving before the split between the San and everyone else. In fact, since the language facility seems to be so perfectly flatly distributed amongst and within all populations, it must have stopped comfortably before the split.

Nelson Mandella’s mother’s family was largely from the San people and his father’s weren’t. Ask Mr. Mandella if he’s noticed any difference between the complexity of the language used by his parents.

People discover remains like ochre and tally marks or other decorations or technological subtleties on human-associated remains from over 50,000 years ago in mainly southern Africa, and say it indicates some symbolic ability which hints that the mental wherewithall for language, and probably language itself, had arrived by that time. And they’re right. But it doesn’t mean we’d only just evolved it. Such remains are rare, and unknown from extremely ancient remains, but it still doesn’t mean we can fix the start date for language after 130,000ya. And there is no reason to suppose that the language facility stopped evolving at 130,000ya. It might have been a long time before that.

If almost no language facility evolution has occurred since that time, it seems to me unlikely that language suddenly started evolving after the Neanderthal/Denisovan branch split off about 400-450kya. Language is so complex yet so automatic and unconscious that it must have taken a long, long time to arrive at its current state. The hyoid bone in the throat of Neanderthals is perfectly consistent with language.

It’s perfectly reasonable to consider language as having been evolving throughout the span of Homo erectus (back to just short of 2mya) perhaps having started before that.

Refs:
Gronau I, Hubisz MJ, Gulko B, Danko CG, Siepel A. Bayesian inference of ancient human demography from individual genome sequences. Nature Genetics 43 1031–1034. 2011

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