The Semitic and Other
Afroasiatic Languages

Genetic Distance and Language Affinities Between Autochthonous Human Populations

The first of the following tables was originally drawn from one article in Scientific American, "Genes, peoples and languages," by Luigi Luca Cavalli-Sforza (November, 1991). This reported the results of genetic mapping of human DNA affinities, the newest theories about larger families of human languages, and a comparison between the two. While this was a thrilling prospect for understanding the early history of languages and the initial dispersal of the human species across the world, some think it is too speculative and questionable for us to have great confidence in the results. Nevertheless, Cavalli-Sforza developed the material in a recent book, Genes, Peoples, and Languages [University of California Press, 2000]. Other recent information on genetic mapping can be found in The Seven Daughers of Eve, by Bryan Sykes [W.W. Norton & Company, 2001].

Since my graduate studies in the 1970's, which included some lingustics, like a course in historical linguistics, using W.P. Lehmann's Historical Linguistics: an Introduction [Holt, Rinehart, and Winston, 1962], I had been out of touch with recent developments. Seeing Cavalli-Sforza's article, the idea that genetic mapping and the higher-order grouping of language families would be logical developments of previous knowledge did not seem so outrageous. It still doesn't. The genetic mapping may still be reasonable enough, though I understand that there are some criticisms. On the linguistic side, however, I now find a very thorough and sensible discussion of the matter in R.L. Trask's Historical Linguistics [Arnold & Oxford University Press, 1996, 1998], "Very remote relations," pp. 376-404. Cavalli-Sforza's table matching linguistic and genetic affinities, like the first two tables here, is included (p. 401). We also have the third edition of Lehmann's book [Winfred P. Lehmann, Historical Linguistics, Routledge, 1992, 1997].

According to Trask, there continues to be little support among those in linguistics for most of the higher order groupings of human languages. Indeed, there is still relatively little support for Joseph Greenberg's proposal that most of the indigenous languages of the New World belong to a single language family, divided (as indicated below) into three branches. (Opinion is even still divided on the grouping of Japanese and Korean with the Altaic languages, there are are no other suggested affinities that I know of.) Trask is fairly respectful of the theory of the "Nostratic" languages, but the basis of most of the other theories ("Eurasiatic," "Sino-Caucasian," "Austric," and "Indo-Pacific") is in statistical comparisons that may not demonstrate any stronger relationship than what can be expected from random and coincidental similarities (or borrowings). For instance, the Persian word for "bad" is bad, just like in English, pronounced with a slightly different quality, but with a vowel very much like the English one. But this is a complete coincidence. There is no other evidence or indication of a common origin (or a borrowing) for these words (though, otherwise, there is plenty of evidence that English and Persian are ultimately related as Indo-European languages).

What is coincidental and what is evidence of affinity becomes a mathematical question, and many of the theorists may be unsophisticated enough in statistics to be unable to distinguish between the random similarities that can be expected and the systematic similarities that are evidence of common origins. The natural occurrence of linguistic change, which is rather like genetic drift in human DNA, may, over a few thousands years, as Trask says (p. 376), obliterate all evidence of origins. The hope for future understanding, however, may be from just such statistical methods as are already used to separate, for audio and images, the "noise" that accumulates from the "signal" that remains. How even to apply those methods, however, is a problem all by itself. Unlike genetic affinities, where the elements of comparison are just the chemical constituents of the DNA, RNA, or proteins, in languages prior decisions must be made about the words or grammatical structures to be compared. Phonetically similar words, for instance, with entirely unrelated meanings will not qualify in the first place for comparison, since it is not just the words but the meanings that are supposed to have a common origin.

In the following charts, the genetic one may be still be taken, with some reservations, as being rather like what we should expect. The linguistics charts can also be taken as reasonably accurate for everything except the groupings, especially the higher order ones, that are marked with question marks. Even these groupings are suggestive, since the idea that most or even all human languages have a common origin is entirely reasonable in itself; and, once the techniques are developed for tackling the evidence, something like these results may emerge. On the other hand, the groupings of the subdivisions of Indo-European languages also seems to be rather more of an open question than some of the articles in Scientific American have suggested. The divisions shown both for Indo-European and Afro-Asiatic languages should be taken as tentative. The ultimate relations of Egyptian are especially problematic because most of the languages to which it may be closely related, the old "Hamitic" group, are only known from their modern versions, while Egyptian is attested from 3000 BC.

The "human evolution" chart, given fourth below, is entirely separate from the others. Its uncertainties are those of an entirely different discipline from linguistics, or even from genetics. It is in physical anthropology where the arguments over the number of human species and their affinities are to be found. Since the ideas there seem to change more or less with the tides, the chart here may be taken as, as Plato says, a "likely story."

Genetic Distance Between Autochthonous Human Populations

"Genetic drift" is the phenomenon by which small mutations in DNA (or RNA, and the proteins that are coded by them) add random variations over time to genetic material, resulting in differences between isolated groups of animals, whether of different species or of the same species that are not inter-breeding. Thus there is about a 5% difference in DNA between humans and our closest Primate relations, Chimpanzees. Between human populations, there is always much less than 0.1% difference. What these differences are and how much they vary can be used to construct a tree showing the relationships between human populations. The following tree is the result of such research, reported by Luigi Luca Cavalli-Sforza. The numbers across the top show the percentage difference in DNA, which is thus no more than 0.03% for all human beings. The most dramatic characteristic of the tree is the division between populations in sub-Saharan Africa and the rest of humanity. This is usually interpreted to mean that modern humans originated in Africa and that the population from which the rest of humanity descended left Africa somewhat less than 300,000 years ago, ultimately replacing earlier humans, like the Pithecanthropines (Homo erectus, like Peking Man, etc.), who had also evolved in Africa but left many thousands of years earlier.

Part of this research was the theory of "Eve," a single female in Africa, around 200,000 years ago, from whom every living human being is now descended. This does not mean that there were not other human females -- there were -- or that we are not descended from them too -- we are. The theory is based on the circumstance that some human genetic material is contained in the mitochondria, little organs in a cell outside the nucleus (where most genetic material is contained). Sperm cells do not pass on their mitochondria to a fertilzed egg and so all human mitochondrial DNA is inherited from the mother. If a woman has only sons (a highly desirable result in many traditional cultures), then her own mitochondrial DNA is actually lost. Over time, this seems to have happened to all lines of descent of mitochrondiral DNA, except one, the line from "Eve." Another interesting feature of the chart is the closeness of American Indians to modern population across Europe, the Middle East, and northern East Asia. Thus, curiously, Europeans are more closely related to American Indians than to Polynesians. Finally, it is noteworthy that skin color is not at all helpful is providing clues to genetic affinity. The darkest colored people on earth, in Africa, India, Melanesia, and Australia, are scattered between groups that are only distantly related. Dark skin color is certainly a function of living under the equatorial sun for many generations, but all human populations have the genetic wherewithal to make that adaptation.

The March 29, 1999, Newsweek reports (p. 72) that population geneticist Jody Hey and anthropologist Eugene Harris, of Rutgers University, reported in the Proceedings of the National Academy of Sciences that, using DNA techniques again, the African population split from the non-African about 189,000 years ago. The article presents this as well before the emergence of "modern" Homo sapiens and somewhat surprising, but it actually seems fairly consistent with the numbers presented above. If Home sapiens goes back 300,000 years and "Eve" is around 200,000 years ago, then it is not beyond the bounds of crediblity that we could get the basic split in the populations not too long after that. The margin of error is also probably pretty large.

Language Affinities Beween Autochthonous Populations

Human Evolution

These charts show what I think is a reasonable current view of human evolution, with various species of genus Australopithecus back in the Pliocene, leading to three species of genus Homo in the Pleistocene. Homo erectus had already spread into Asia, as far away as China and Java, but the archaic form of Homo sapiens, as seen in the genetic tree above, spread into Asia all over again. The blue names and lines are for the glacial episodes that characterize the Pleistocene. The names given are, first, for North American (e.g. Wisconsinan), second, for Europe (e.g. Würm). The scale at left is the logarithm of the year, which compresses the Pliocene, even though it was actually longer than the Pleistocene.

These names of glaciations are now no longer seen, and they even seem to be something of an embarrassment. Evidentially, the difficulty in dating the original glaciations was because there really are many more of them (perhaps a hundred), which, as I far as I can tell, have not been identified or named in any systematic way. Meanwhile, the old names have abruptly disappeared, even from books about glaciation, without any explanation of the change in thinking, or the recognition of evidence, that rendered them obsolete. This is not the proper way to do science, where mistakes must be examined as thoroughly as anything else.

Views about human evolution are constantly under revision, as they have been for decades. No great reliance should be placed on any of them. Recently several new fossils have been found, multiplying the number of species again. The new taxa may or may not be permanent. One of the longest running arguments is over the Neanderthals (i.e. "New Man [Neumann] Valley"), whether they are in the main line of human evolution or form a doomed offshoot among the glaciers of Europe. The "doomed offshoot" view may be the most common now, though not long ago there was a claim that distinctive Neanderthal tooth characteristics still exist in European populations, and there is considerable evidence of intermediate forms, though these are often ascribed merely to crossbreeding. The argument is likely to go a few more rounds before, if ever, being settled. Nevertheless, now there is an approach that may put the matter beyond doubt. Genetic material can be recovered from Neanderthal bones, and Bryan Sykes (The Seven Daughters of Eve [W.W. Norton & Company, 2001]), says that, on the basis of the DNA evidence, no modern Europeans have turned up who genetically are descendants of Neanderthals [pp.125-126]. It is hard for a layman to argue with such an approach, and the "doomed offshoot" view now may be said to be credibly affirmed -- except for every more recent claims about intermarriage of Neanderthals with modern humans in Iberia. I am not sure what kind of genetic evidence there is for that.