Language & Genes
Often while arguing against the Steppe hypothesis which argues that Indo-European languages spread out of Pontic Steppe by pastoralists from 3000 BCE onwards, people claim the languages and genes are not correlated, language is just a meme that can be transmitted without demographic changes. While this argument can somewhat be made to work in the 21st century I do not think languages could have been spread in pre-modern societies without migrations.
I firmly believe that ancient genetics is the strongest method for unraveling the mysteries of prehistory. For pre-modern societies, I do not believe there were any mechanisms of the spread of primary languages without mass movements of people. Language is a meme but unlike religions, it has complex mechanisms of spread that take years and requires (in most cases) familial teaching. If we take examples of memetic spread in recorded history — be it the spread of Islam in Southeast Asia or Buddhism in East Asia(via trade, etc) both happened without fundamental alterations in the primary language of the recipient regions. So in essence I do not find the model of primary language shift through mechanisms of trade or other N mechanisms posited as feasible.
Everywhere on the earth where Indo-European languages were spoken as primary languages in pre-modern times, the Steppe genetic signal is present in substantial amounts. I do not think any other explanation other than some form of Steppe hypothesis can explain this data. Of course, PIE homeland (including Hittite) could be in the Steppe or it could be elsewhere. I believe what we can firmly state is not where PIE originated, but where PIE developed and was spread out of.
If we want to look at a potential model of IA spread into India from the historic record we can take a look at the British isles. The languages are nicely split in the east-west direction along Germanic/Celtic lines similar to the North-South split of Aryan and Dravidian languages in India. Not only that only around 38% ancestry of Britain is Anglo Saxon with an east-west gradient.
Critics of OIT like to attack particulars of the 2007 Anthony book as new evidence is unearthed as if any dissonance in Anthony/Mallory model is a slamdunk against the Steppe hypothesis. Personally, I have no strong positions on the details of the Steppe hypothesis as argued by Anthony and Mallory. The evidence of horseback riding for the Sredny Stog or even the Yamnaya is circumstantial at best (I believe some form of horseback riding as a tool of herding by young shepherds might have been a possibility), so we cannot firmly assume that horseback riding was the reason for the massive demographic changes brought about by the Steppe men. This might have mattered before the ancient DNA revolution, but now we know the genes of the steppe pastoralists spread, maybe because of the horseback riding or maybe just due to the benefits of horse husbandry or some other reasons. We know massive demographic and (probably) linguistic changes occurred from the Steppes, the “how” question might eventually get solved (or it might not) — but that doesn’t poke holes in the larger “Steppe hypothesis” built on top of Archaeogenetics.
This doesn’t mean that any other mechanism of IE spread cannot work with the available data but it has to go beyond the tenuous mechanisms like trade-aided language spread. Even the Elite migration hypothesis (minus demographic changes) doesn’t seem to work as well as we assumed before the ancient DNA. The Hittite and Mitanni IE elites did not cause any substantial demographic changes nor did they cause any long-term linguistic alterations in the middle eastern region. Closer to home, Indians have had elite rules who spoke Greek, Iranian languages, Turkic languages, and lastly English. These massive elite dominations for centuries have only resulted in superstrates and languages like Urdu (I am not sure if we call it a creole). By the end of an efficient British Raj, not even 1% of Indians spoke English as a primary language. Thus anyone who tries to explain away IA spread out of India has to account for the 20–30% paternal ancestry (50% Y chromosomes) which seems to have changed in the other direction. This paternal ancestry matters a lot as we know the ancient Aryans were patriarchal, patrilineal, and patrifocal.
Also, it is often overlooked that AIT is just one node of the larger PIE — Steppe hypothesis. Even if details of AIT are contested how much does that matter to the PIE question? Also even if PIE shifts out of Pontic Steppe into Iran or Anatolia it would still be against any model for OIT and in favor of some form of AIT.
Personally, I would be open to alternative scenarios to explain the IA spread into India, like IA migration during the IVC (before the Sintastha) while migrations downstream of Sintastha which are attested via Genetics being responsible for the consolidation of Aryas as Kshatriya/Brahmana elites of the Vedic age. But these are extraordinary scenarios and they would require at least some robust objective pieces of evidence like
- Steppe signal from before 2000 BCE.
- Chariots or other classical IE motifs before 2000 BCE.
- Or deciphering of IVC script (or any other script from ancient India) to a Sanskrit-like language.
Outside the world of religion and mathematics, there is no absolute certainty. As a result outlier individuals from academic disciplines will continue to have non-conformist takes (like Kazanas for example). Such takes over the decades will continue to be used to create elaborate theories, be it using linguistics, genetics, and something else and they will continue getting traction in some groups (European pagans, Serb nationalists, Indian nationalists). The solutions to the PIE question are models, some more parsimonious; some tenuous, others ridiculous. There is certainly enough circumstantial data to spin wild theories putting the homeland from Iberia (initial bell beakers) to Gangetic plains (OIT), but none of these theories is the best fit for the data we have today. Maybe with newer data, some better candidates can emerge (though I doubt it). But going by the academic consensus from 3 fields -> Genetics, Linguistics, and Archaeology some model of the Steppe hypothesis is the best fit for the Indo-European question.
But for all, we know someone can still spin a theory based on some evidence that puts the PIE homeland in the sunken Atlantis.