 Hello and welcome to NewsClick. Today, we have with us Dr. Satyajit Ra. Satyajit, we have yet another recent paper in evolutionary biology and it seems to flesh out in much more detail what we have discussed earlier that we have had multiple migrations into India. We have had Indo-Aryan speakers, language group speakers who seem to have come from outside. It seems to have been more a military domination therefore difference between matrilineal and patrilineal genetic markers. What do you think is new in this paper? So, quite frankly, I love this whole trajectory of work and for a number of reasons. One is that rather than providing simplified, simple-minded answers to our origins, it provides increasing complication and nuance, which is how it should be in my eye. Secondly, because it comes from publicly available data. This particular paper that you are referring to, which was published in a journal called BMC Evolutionary Biology, actually is an analytical approach that doesn't depend on these people, the investigators, the authors, having to go out, collect blood samples, do DNA sequencing and then treat the sequence data as their data. Instead, they are investigating the data commons. They are using methodologies, they are taking advantage of the fact that the data commons have grown, that the body of available data in the commons is grown and they are using what appear to be somewhat differently configured analytical investigative approaches to provide, as I said, complicating nuance to the human story. What is new is it begins to provide much greater detail into the story of the peopling of the subcontinent and three different issues I think are worth highlighting as issues that the paper through brings up. One is that the notion that humanity expanded out of Africa as a one-dimensional trajectory over time, which was always in lived experience a nonsensical idea, that made it- That's not how normal migrations take place. That's not how lives are lived over over generations. And yet, the way it is quite frequently posited is as though we were an exploring species that went forth to some goal of at least adventure. Instead of simply communities going from here to there and then from there to somewhere else and then coming back and going back quite remarkably, this paper provides genetic footprints of bi-directional migrations. The second is a version of the same that it's not as if 60,000 years ago we came from there to here and then no more. That's not how lives would be lived. We would go and then not only would we come back, but we would go again and then we would go again and then we would go again. And over thousands of years, we're talking about thousands of years of traditions, these comings and goings would be in very different social historical contexts. And the data begin to provide indicators and footprints for multiple migrations each somewhat differently configured enough to allow us to dovetail it with archaeology, with history, with at least textual history, with linguistics to begin to have a synthesized view of who we are and where we come from. The last point which inevitably ends up being treated as the most striking point is the clear dichotomy, although I will say that it is the weakest part of the paper, but such as it is the clear dichotomy between metrilineal genetic inheritance and what that shows and petrilineal genetic inheritance and what that shows and the discordances thereof. And again, inevitably, the implications of that discordance in terms of patriarchy at one end and of a broader canvas of social history of incursions of communities into the subcontinent at the other end. We can talk more about that, but that's what's new about this. One part is the central Asian footprint seems to be quite clear and that footprint is again not one incursion, but a set of migrations that take place. So, that's an interesting directional flow as it were and it seems to also show that the basis of what archaeological evidence and linguistic evidence people have said that essentially Indo-Aryan speakers came from Central Asia into India and also carried the Vedic shall we say the Vedic compositions as well as the language. So, that seems to be quite strikingly corroborated if you will by the kind of migration patterns if you will, of course, it doesn't prove what is the language they spoke, but it seems to be quite a strong correlation. So, let me complicate that rather than disagree, let me complicate that. So, there is an ancient relatedness between Far West Asian, Arabian Peninsula, if you will, genetic influences in South Asia. It's not that there is not, of course, when you come out of Africa, geographical contiguity would make it plausible and indeed, there is in the paper itself, there is some measure of that, but those seem to be older. 9000 years. There are there are caveats, but those seem to be older. The more recent ones, so the more recent ones appear to be mediated by a more indirect route. Anatolia, Iran, Central Asia as in between the seas and down to us. That's one issue. The second is, and this one is really interesting, they point out that the genetics in order to be properly understood needs to be dissected, if you will, between periodic local expansions of population and incursions of populations of related genes, of related genetic mica. And their data seem to indicate some degree of success in this deconvolution. And what that provides is a snapshot of when the subcontinent had bursts of local expansion, and you would think bursts of local expansion of populations would be related to particularly favorable long-term conditions for population growth. So all major technological advances like agriculture. I'm actually including that in my argument of environmental circumstances. Climate alterations, climatic alterations, but also, as you point out, technological alterations of agriculture, of fire smelting, metal A versus metal B and so on and so forth. And beginning to see how those periods of expansion and the periods of ingression of communities match with each other will begin to provide a very interesting picture of how in the region, in the broader region, there was a population expansion locally that may perhaps have also not just accompanied but have caused an enabling of between population migrations as well, as one can make historically plausible narratives out of this which I'm trying not to do. So that's one issue. There are expansions like that going very far back, 40,000 years, 45,000 years in the paper is one of the expansions stated at, I'm remembering dates correctly. From Central India expansion that took place, yes. So and the microlith technology, if you will, that's one of the things that I talked about. So the paper is of remarkable interest for this landscape of nuance as I'm calling it. You're perfectly right. The evidence also suggests that over the past three, four, five, thousand years, thereabouts, there has been a newer wave of centralation in ingression and that newer wave on the limited data that they have appears to be far more prominent in paternal lineages than in maternal lineages. All of this depends on paying attention to what is not mainstream. And let me explain that. So it is not their case that all of our genetic service station or centralation or anything, they are pointing out that bulk of our genetic inheritance is of course local because migrations do not mean or mass replacements of communities one by the other. They usually mean incursions, whether peaceful, violent, strained, amicable, whatever, incursions over a period of time of small numbers with perhaps disproportionate cultural influences and consequences. But in genetic terms, small contributions, particularly given the ever present reality of patriarchy, the fact that men will have a disproportionate influence, disproportionate numbers on the genetic makeup and equally on cultural makeup. All of this begins to dovetail together in these data so that the idea that the Aryan invasion somehow replaced a preexisting gene pool is of course aren't nonsense. But on the other hand, what the small, unreguarded, minor footprints in our genes tell us about who came from where and how is remarkably interesting. We have to pay attention to the three percent, five percent, nine percent components of our genetic landscape in order to appreciate that there is a gradient of West Asian and Central Asian genes in the subcontinent going eastwards, southwards and eastwards and that the relative proportions of the prominence of this small footprint differs radically between maternal and paternal gene. Thank you very much, Satyajit, for being with us. 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