Genetics Might Be Settling The Aryan Migration Debate, But Not How Left-Liberals Believe

South Asia (Wikimedia Commons) 
  • Given the importance of Aryan migration in the Indian history, it is necessary to challenge the one-sided presentation of facts in a recent article . There seems to be much that is questionable in its approach, and this deserves scrutiny.

Writing in The Hindu, Tony Joseph has claimed that genetics has very “sure-footedly” resolved the debate about whether there was a migration of Indo-European people (“Aryans”) into the subcontinent around 2000-1500 BCE – apparently, the “unambiguous answer” is yes. To anyone with a nodding acquaintance with the literature in the area, such an assertion is unfounded. Given the sheer importance of this topic to Indian history, it is necessary to challenge Joseph’s one-sided presentation of facts. There also seems to be much that is questionable in his very approach, and this deserves scrutiny.

Conclusions decided upon in advance?

Ironically, after saying that the dominant narrative so far that genetics had “disproved” Aryan immigration had not been nuanced, he abandons nuance himself.

Noting the clear slant in his article, and his quoting of Razib Khan, who was sacked as a columnist by the New York Times apparently for racist views, I got in touch with Dr Gyaneshwer Chaubey, senior scientist at the Estonian Biocentre, Tartu, and a widely-published scholar in the area. Indeed, Chaubey is a co-author with Peter Underhill (whom Joseph quotes) of the 2015 study on the R1a haplogroup that Joseph cites in his article.

To my surprise, it turned out that that Joseph had contacted Chaubey and sought his opinion for his article. Chaubey further told me he was shocked by the drift of the article that appeared eventually, and was extremely disappointed at the spin Joseph had placed on his work, and that his opinions seemed to have been selectively omitted by Joseph – a fact he let Joseph know immediately after the article was published, but to no avail.

Having known Chaubey’s views for some time now – especially that the origin of the R1a is far from settled – I was not surprised to hear this. This in itself gives the lie to Joseph’s claims of the “unambiguous conclusions” of genetics about the hypothetical Aryan immigration.

Mitochondrial DNA vs Y-chromosomal DNA

Joseph claims that we only had mitochondrial (mt-) DNA (which is inherited from the mother) analysis till recently, which failed to capture the fact that it may have been mostly Aryan males who migrated first to the subcontinent and intermarried with the native women. This, apparently, has been conclusively established by a recent “avalanche” of Y-chromosomal DNA (which is inherited exclusively by sons from their fathers) data, which shows a Bronze Age gene flow into the subcontinent. This remark seems to suggest an embarrassing lack of familiarity with the literature.

Also, does Joseph seriously imagine geneticists would not have envisaged the possibility of males spearheading a migration all along? The first suggestion that Y-chromosomal DNA analysis may be making a case for Indo-European immigration, and the proposal that the R1a haplogroup (M17) may be a marker for this migration, was made as early as 2001.

This was subsequently contradicted in 2006 in a seminal Y-chromosomal DNA study by a group that included Richard Villems, Toomas Kivisild and Mait Metspalu, also of the Estonian Biocentre, and among the leading authorities in this area (Kivisild has since moved to Cambridge, but Villems and Metspalu are Chaubey’s current colleagues at Tartu). Villems and Kivisild were, in fact, co-authors in the 2001 paper I just mentioned, but revised their view about a migration after a fresh analysis of more extensive data.

This paper, concluded, “It is not necessary, based on the current evidence, to look beyond South Asia for the origins of the paternal heritage of the majority of Indians at the time of the onset of settled agriculture. The perennial concept of people, language, and agriculture arriving to India together through the northwest corridor does not hold up to close scrutiny. Recent claims for a linkage of haplogroups J2, L, R1a, and R2 with a contemporaneous origin for the majority of the Indian castes’ paternal lineages from outside the subcontinent are rejected...”

The “dominant narrative” that Joseph talks about actually stems from this study, and I’m not sure he is qualified to dismiss it as “a bit of a stretch”. This study, which has never really been contradicted, is, in fact, published in a much more respected journal than BMC Evolutionary Biology from where Joseph cites Martin Richards’ paper. This is significant, as good studies in this area have generally found a place in highly-ranked journals, even if they have arrived at diverging conclusions.

Indeed, this itself would suggest there are very eminent geneticists who do not regard it as settled that the R1a may have entered the subcontinent from outside. Chaubey himself is one such, and is not very pleased that Joseph has not accurately presented the divergent views of scholars on the question, choosing, instead to present it as done and dusted.

The R1a haplogroup

There are some inherent issues in regarding the R1a as a marker for any hypothetical Indo-European migration.

Firstly, Iranian populations, who are also speakers of the Indo-Iranian family of languages like most North Indians, have very little R1a. Also, tribal groups like the Chenchus of Andhra Pradesh and the Saharias of Madhya Pradesh show anomalously high proportions of R1a. The Chenchus speak a Dravidian language, and the Saharias an Austro-Asiatic one (though they have recently adopted Indo-European languages).

They are hunter-gatherer peoples who remained stunningly isolated without admixing much with other population groups, and consequently, their lifestyles have remained startlingly unchanged for millennia, as they would have been before the start of settled agriculture.

The best that studies which argued that the R1a could be used as a marker for the hypothetical Indo-European migration could do was to simply ignore these groups as aberrations. But is that very convincing? Note that it is possible – no, almost certainly the case – there were many tribal communities with high proportions of R1a that, unlike the Chenchus and Saharias, were assimilated into the caste matrix over the millennia. So how correct is it to link the R1a with an Indo-European migration?

Significantly, Richards et al acknowledge Chaubey’s “critical advice” with their manuscript. That seems like a euphemism for saying that Chaubey (and, by extension, the Tartu school) had reservations about their conclusions, which is probably why he is not a co-author. So what should one make of Joseph’s claim that geneticists have “converged” on an answer?

If Underhill expressly stated to Joseph that he has now reversed his published position that there has been no significant genetic influx to Asia from Europe, indeed specifically that he is now convinced the R1a entered the subcontinent from outside, Joseph bafflingly does not reproduce this statement in his article.

The statement Joseph actually quotes merely points out that we have better data now, but that is not the same thing. Joseph also cites his 2015 paper, in which Chaubey is a co-author, but this paper actually underscores the limits of current technology, and says their data is too preliminary to jump to conclusions about migrations and culture shifts.

The genetic data at present resolution shows that the R1a branch present in India is a cousin clade of branches present in Europe, Central Asia, Middle East and the Caucasus; it had a common ancestry with these regions which is more than 6000 years old, but to argue that the Indian R1a branch has resulted from a migration from Central Asia, it should be derived from the Central Asian branch, which is not the case, as Chaubey pointed out.

In other words, contrary to what Joseph claims, as the Y-chromosomal DNA data stands today, there is no support for a recent migration into the subcontinent.

Ancestral North Indians (ANI) and Ancestral South Indians (ASI)

Joseph continues to tilt at windmills when talking about the ANI / ASI construct of David Reich et al., who used analysis autosomal DNA, which is different from mt- and Y-chromosomal DNA.

Joseph writes, “...this theoretical structure was stretched beyond reason and was used to argue that these two groups came to India tens of thousands of years ago, long before the migration of Indo-European language speakers that is supposed to have happened only about 4,000 to 3,500 years ago.”

One doesn’t know what to make of this. It was geneticists – including Lalji Singh and K Thangaraj who were Reich’s co-authors in the paper which proposed the ANI/ASI construct – who argued that the ANI and ASI are considerably more than 12,500 years old, and not the result of any recent migration.

He then goes on to quote David Reich arguing in favour of a migration from the Steppe around 2500 BCE. Once again, Joseph presents this view as the last word on the subject, although not all geneticists agree.

For instance, Partha Majumdar and co-workers have very recently come up with quite different conclusions in the journal, Human Genetics: “In contrast to the more ancient ancestry in the South than in the North that has been claimed, we detected very similar coalescence times within Northern and Southern non-tribal Indian populations. A closest neighbour analysis in the phylogeny showed that Indian populations have an affinity towards Southern European populations and that the time of divergence from these populations substantially predated the Indo-European migration into India, probably reflecting ancient shared ancestry rather than the Indo-European migration, which had little effect on Indian male lineages (emphasis mine).”

The Evidence From Archaeology

Since Joseph believed he was shocking those who believed genetic analysis had disproved Aryan immigration theories, I shall return the favour.

Hypotheses of migrations of Bronze Age populations into the subcontinent fall afoul of archaeological evidence. Paradoxically, as I have described earlier, bronze itself goes missing from the archaeological record for several centuries that are supposed to correspond to the settling of the Bronze Age Indo-Europeans into the subcontinent. As one of the foremost authorities in the archaeology of the Indus Valley Civilisation, Professor Jonathan Mark Kenoyer of the University of Wisconsin points out, this actually reflects a prolonged lack of contact of the subcontinent with the regions the Aryans are supposed to have entered from.

Also, geological evidence shows that the Ghaggar-Hakra river, along whose channels numerous Harappan sites have been discovered, was the River Saraswati described in the Vedas and other ancient literature; indeed, the team of geologists led by Peter D Clift which carried out the geological studies asserted that the descriptions of the Saraswati in those texts was remarkably accurate, as I wrote in an earlier article.

Such findings negate the Aryan immigration model, establish the overlap (if not identity) of the Indus Valley and Vedic cultures, and push back the dates for the composition of the Vedic and other literature considerably.

Agriculture In Subcontinent Indigenous, Autochthonous

There is clear evidence of continuous inhabitation of the Gangetic plain from the Pleistocene. It is also abundantly clear that agriculture was developed indigenously, autochthonously, based on exploiting local resources, at multiple centres on the subcontinent – the Saraswati-Indus region, the Gangetic plain, Eastern, Central and Peninsular India – in a natural progression from a hunting-gathering lifestyle to a sedentary one, with no external stimulus, but with strong interaction between various regions of the subcontinent themselves right from the earliest Neolithic.

The myth that the founding of agriculture, whether in the Indus Valley or elsewhere in the subcontinent, is owed to migrations from West Asia (the so-called Fertile Crescent) is not supported by archaeological evidence.

Based on current evidence, whether genetic or archaeological, Joseph’s conclusion that, “...we are a multi-source civilization, not a single-source one, drawing its cultural impulses, its tradition and practices from a variety of lineages and migration histories,” is quite simply totally wrong.

One cannot impressed by Joseph’s quoting of a blogger with a very questionable history like Razib Khan, while selectively omitting the comments of a known scholar in the area like Dr Gyaneshwer Chaubey after having sought them himself.

Can one be sure he has not interviewed other scholars, but left out their views from his article as they didn’t suit his pre-determined agenda – or just didn’t interview scholars he felt held such views?

Joseph and others like him are welcome to write on any topic they please, and are even free to take sides in line with their prejudices. Indeed, all he has done is to paint a very recent paper in a not particularly highly-ranked journal as the final word in the debate, while coolly ignoring well-regarded studies which arrive at differing conclusions in significantly higher-ranked journals.

All one asks is, when writing on a much-debated topic like this one, they should at least show the intellectual sincerity to mention divergent points of view, and not try to create a false impression for the lay reader that they have been conclusively addressed. That is neither very honest nor commendable.

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