Population geneticists have identified two objects that carry genetic information that is passed on from generation to generation. They are the mitochondrial DNA (mtDNA) and the Y-chromosome. mtDNA is inherited through the female line (passed on from mother to daughter) while the Y-chromosome is transmitted through the male line. There are individual quirks in these cells that are specific to regions like Africa, India, Southeast Asia and so forth. These are the genetic markers we look for. Mapping them allows us to study the possible origins of different population groups now inhabiting the globe. For example, we know that all humans living in the world today are descended from a relatively small African population because Africa contains almost all the genetic markers found in other parts of the world, but the reverse is not true.
Following more than a century of research in genetics, especially molecular genetics, it is becoming possible to trace the origins of different population groups in the world. It is important however to approach it with care because it has some pitfalls. In particular, since all humans living in the world today have more than 99 per cent of their genes in common, almost any two groups can be found to be genetically similar. Failing to recognise this has led to absurd conclusions like the claim that upper caste Indians are of European origin, who ?imposed the oppressive caste system? on the indigenous population. (No ?oppressor gene? has been found.)
The error here lay in assigning biological causes to a man-made classification like caste. Nature, however, does not recognise man-made boundaries. Similar claims can be made for religion? finding a genetic basis for Christianity. Taking this a step further, one may identify Catholic genes, Protestant genes, and presumably even Mormon genes in Salt Lake City, Utah, the home of the Mormon Church, where the claim about genes and caste was first made.
Similarly impossible claims have been made about language, social habits and the like that can have no biological basis. The error consists in mistaking the phenotype for a purely inherited trait or genotype. In addition, some workers have tried to use genetics to justify their own pet beliefs and theories like the Aryan invasion. This has led to absurdities like one group claiming that only males migrated (more of which later) while another claimed only females did! Obviously both cannot be true, but both can be false.
After some initial hiccups, the definitive statement about the genetic composition of the Indian population was summarised as follows by researchers led by Luigi Cavalli-Sforza:
Taken together, these results show that Indian tribal and caste populations derive largely from the same genetic heritage of Pleistocene southern and western Asians and have received limited gene flow from external regions since the Holocene. The phylogeography [neighboring branches] of the primal mtDNA and Y-chromosome founders suggests that these southern Asian Pleistocene coastal settlers from Africa would have provided the inocula for the subsequent differentiation of the distinctive eastern and western Eurasian gene pools.? (Italics added.)
Noting that mtDNA is carried by the female line, while Y-chromosome is passed on through the male line, what this means is that the Indian population is largely indigenous in origin and has received negligible external input (gene flow) since the end of the last Ice Age (Holocene). This means that various migration theories like the Aryan invasion in 1500 B.C.E. simply cannot be true.
The Oxford geneticist Stephen Oppenheimer is more specific and also more emphatic, focusing on the M17 or the so-called ?Caucasoid? (politically correct for ?Aryan?) genetic marker:
?South Asia is logically the ultimate origin of M17 and his [Sic] ancestors; and sure enough we find highest rates and greatest diversity of the M17 line in Pakistan, India and eastern Iran, and low rates in the Caucasus. M17 is not only more diverse in South Asia than in Central Asia, but diversity characterises its presence in isolated tribal groups in the south, thus undermining any theory of M17 as a marker of a ?male Aryan invasion? of India.
So there was no Aryan invasion? by males or by females. This also means that the tribal or the so-called ?indigenous? populations of India are not any different from the people making up the bulk of the Indian population, which is what Cavalli-Sforza and his colleagues also found. As Oppenheimer observes, genetics is quite specific on this point.
One age estimate for the origin of this line in India is as much as 51,000 years. All this suggests that M17 could have found his [Sic] way initially from India or Pakistan, through Kashmir, then via Central Asia and Russia, before finally coming to Europe. (Ibid)
It is worth noting that this is the exact reverse of the scenario postulated by various invasion/migration theories including the Aryan invasion theory. This is by no means the last word on population distributions, but new findings are unlikely to salvage these 19th century theories or their modern incarnations founded on linguistics, racial ideas and political needs.
Conclusion: from Galileo to Max Planck
Seen against this background of evidence from a wide range of sources?from natural history and genetics to literary and archaeological records?the idea that the Indian civilization developed in a few centuries, seeded by small groups of invading (or migrating) ?Aryans? from the Eurasian steppes cannot be taken seriously. But this is only in hindsight. The fact remains? it was taken seriously, and even today, when one would expect a more enlightened attitude towards facts and evidence than what prevailed in the nineteenth century, various devices are being employed to somehow prevent it from collapse. The recent controversy over the proposed changes in the California school curriculum is only latest episode in this ongoing battle to replace these theories with a new approach based on facts and logic.
This phenomenon of an established order resisting change has a long history. Even in the exact sciences, change rarely takes place without a struggle. The most famous of these is probably Galileo'sstruggle with the Church leading to his Inquisition. History books present this as a classic case of religious dogma against science, and point to Galileo as the victim of the struggle of knowledge against dogma and superstition. This is a serious distortion of the true nature of the conflict. What Galileo challenged was not the authority of the Church?he was a devout Catholic?but the worldview of his contemporaries. This worldview held that the empirical method and mathematics?both products of the human mind?could not be applied to the study of the heavens, which they held was the creation of God. According to them it was only theology that could explain the heavens? not experiment and observation, much less mathematics.
This is an important point frequently lost in the oversimplification involved in seeing Galileo'spersecution as a case of science against religion. His adversaries, who prominently included Cardinal Bellarmine, saw themselves as scientists. It was only when they failed to defeat him in the scientific arena that they resorted to influencing religious and political authority represented by the Vatican, then the paramount power in Italy. More than religion, Galileo'schallenge was to theology as the pre-eminent tool in the study of the world. We now see mathematics as the queen of sciences. In Galileo'stime, that position was held by theology. According to Galileo, ?the universe is written in the language of mathematics.? This was something that philosophers (i.e., ?scientists?) like Cardinal Bellarmine would never concede. To them, universe was God'screation and only theology could be the legitimate tool.
To a historian of science, there is a remarkable similarity between the attitudes of theologians in Galileo'stime and of philologists and anthropologists in our own. They cannot accept the fact that the very foundation of their discipline?not just the Aryan invasion theory?has collapsed. Natural history and genetics have demolished their theories as well as their methods. And like Galileo'sadversaries, they too have chosen to resort to politics and propaganda, though the forces they invoke lack the authority of the Church in Galileo'stime.
Progress, however, does not respect position and prestige. It is unlikely that the proponents of the Aryan theories will be able to turn the clock back or stem progress. What can we expect? Will they recognize that their positions are doomed and learn new facts and master new methods? Highly unlikely. Max Planck, one of the founders of quantum physics that went on to revolutionize physics once observed:
An important scientific innovation rarely makes its way by gradually winning over and converting its opponents: it rarely happens that Saul becomes Paul. What does happen is that its opponents gradually die out and that the growing generation is familiarized with the idea from the beginning.
If history is any guide, it will be no different with the Aryan theories. We are unlikely to convert the existing adherents: they have too must invested in it, and too set in their ways to change. The most we can expect from them is old wine in new bottles? like AIT being served up as the Aryan ?influx? theory instead of the Aryan ?invasion? theory. Time and progress will take care of them.
So there is little point in engaging beyond an occasional rebuttal of their claims. What we should be focusing on is the next generation of researchers and pave the way for their work. We should be devoting our time and energy less to fighting these ghosts from the past and more to building a foundation for the younger generation. We can begin by highlighting the importance of some crucial factors like ecology and climate change that have been all but ignored by historians and anthropologists for over a century. We can also emphasize the importance of multidisciplinary approaches that combine science and literary records.
In summary, returning to the present situation, let us accept this well established scientific fact: outside of Africa, South Asia contains the world'soldest populations, and modern Europeans are themselves among the peoples descended from migrants from India, going back more than 40,000 years. There exist ample materials from diverse sources ranging from natural history and archaeology to literature and astronomical records that testify to this.
Let us study them and learn about the people who created them without resort to labels and stereotypes like ?Aryan? and ?Dravidian.? Our time horizons should also change from centuries to millennia, and even tens of millennia. We need to understand more about the impact of climate change, especially during the transition from the Ice Age to the Holocene. (The Holocene is the present interglacial or warm period in which we are living.) This should be the starting point for studying history in the Holocene or the post Ice Age period.
(The writer is a former U.S. academic and industrial researcher. His latest book is Sarasvati River and the Vedic Civilization: History, science and politics.)