Skip to comments.Out of Africa? Data fail to support language origin in Africa
Posted on 02/20/2012 8:24:25 PM PST by SunkenCiv
Last year, a report claiming to support the idea that the origin of language can be traced to West Africa appeared in Science. The article caused quite a stir. Now linguist Michael Cysouw from Ludwig-Maximilians-Universitaet in Munich has challenged its conclusions, in a commentary just published in Science...
Atkinson based his claim on a comparative analysis of the numbers of phonemes found in about 500 present-day languages. Phonemes are the most basic sound units -- consonants, vowels and tones -- that form the basis of semantic differentiation in all languages. The number of phonemes used in natural languages varies widely. Atkinson, who is a biologist and psychologist by training, found that the highest levels of phoneme diversity occurred in languages spoken in southwestern Africa. Furthermore, according to his statistical analysis, the size of the phoneme inventory in a language tends to decrease with distance from this hotspot. To interpret this finding Atkinson invoked a parallel from population genetics. Biologists have observed an analogous effect, insofar as human genetic diversity is found to decrease with distance from Africa, where our species originated. This is attributed to the so-called founder effect. As people migrated from the continent and small groups continued to disperse, each inevitably came to represent an ever-shrinking fraction of the total genetic diversity present in the African population as a whole.
(Excerpt) Read more at physorg.com ...
We look like we do because it pleased G_d to make us in his image. And we, like all other species, were planted here on Earth in G_d’s garden.
Arboreal or aquatic origin is just so some people can get grant money and continue to live the life style they would like to become accustom to.
And now let's get really radical. Every one is looking at this issue from the wrong viewpoint: our own.
Try looking at it from G-d’s point of view. Does He see physical form as the indicator of one species or another, or does He see species as the content of the spiritual essence?
If that were the case, it makes it possible to have had others on the Earth who looked like us, but were a different species.
This could also hold true in the present, which would explain liberals and conservatives, and so on.
Having raised the rabble, let the riot commence ...
True, it doesn't go as far back as the fossils you were talking about, but what I find fascinating is that fossils of European type humans were found in South America, which date back (roughly) to when the Americas were colonized by Asians. I'd love to know what happened with them. If they interbred with the Asian settlers, there should still be some ancient European genetic markers in the populations in those areas.
Such a drastic loss from the gene pool would drastically alter any pace or direction of evolution, if there is such a thing.
One cannot postulate that a putative evolution of the human species was either static or dynamic prior to the super volcanic eruption of Toba, since there is no found surviving evidence either way.
I think that the effect of the Toba eruption is still debated.
I will, however, say that the rate of evolution of the human species has changed little. If I define the rate of evolution as being the rate at which mutations in the DNA enter the germline and become heritable, then the rate of evolution is more or less constant. I think that people perceive evolution as speeding up or slowing down at various times. In reality, those times coincide with events that affect selection pressures. A mutation that has been neutral or slightly deleterious in one environment might be advantageous in another, effects we would see if (for example) a volcanic eruption caused local weather patterns to change (e.g. by diverting the prevailing winds) and a dry climate became wet.
Further, for the survivors of Toba to be able to generate successful descendants, they would have had to be a single group, else there would have been too few for a successful gene pool - and we would not exist.
Hmm. I have no idea how many individuals of a population there must be in order for a species to survive. It probably has something to do with the genetic variation present in the population before most of them were killed off. Interesting questions.
What is certain is that we can make all kinds of hypotheses, but finding the evidence to support them is a real challenge. Well, if science were easy, people like me would have to find other professions!
The drift between the major races is great. The apparent time span is equally great. The idea that the races were isolated for such a long time troubles me. I would expect that the nomadic life of early man would have led to greater intermingling among the races, especially in Eurasia, and a more blended result.
The answer to that is that evolution does not occur in response to a change in environment. Evolutionary changes are random. If a change confers an advantage in a particular environment, organisms with that new trait will have a survival advantage over organisms without it, and they will reproduce faster. If we see a trait that confers an advantage in one population, but not another that lives in a similar environment, we can assume the mutation only happened in one population. There is no reason separate populations would have the exact same mutations.
Early humans might have been nomadic, but they never traveled far from their birthplace. So, even groups a few hundred miles apart might have become genetically quite distinct from each other. With modern travel and intermarriage, some of those genetically distinct groups are disappearing. I read of one population in Japan that only has a couple of dozen members left, because everyone else married outside of the group.
I appreciate the thought. I still have some doubt. One is cultural. The Shakers held a belief not to procreate. They made themselves extinct in the same environment others thrived. In the same way, Europe may become a mid-east/African majority simply because white people refuse to procreate at the same high rate. Both live in the same environment. I see a cultural aspect to evolution which favors or punishes the tribe for its cultural beliefs.
How that works over long time periods is a mystery to me.
When you get to cultural effects on evolution, you just add a new level of complexity. The behavior of individuals most certainly affects evolution, not just in humans but in many species.
Another complication are the traits which confer both advantages and disadvantages. For example, many female birds like to mate with brightly colored male birds. But brightly colored male birds cannot easily hide from predators. So there are two opposing forces affecting male bird color.
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