For those who aren’t aware, I got into a bit of an argument with Razib Khan over the results of a recently released genetics paper. The full exchange can be read at the above link, but I’ll also provide a summary here (as well as my final thoughts on the topic). This will be a very long read, so prepare yourself.
A couple days ago Razib posted an article (linked above) titled, “Pakistani British Are Very Much Like Indians Genetically”, where he argues that Pakistani-Punjabis were traditionally part of the same Hindu cultural milieu as the rest of India, and were not the mlecchas they are condemned as in works like the Vedas, Mahabharata, and Dharmasutras⁰.
His evidence for this is a recent study on British Pakistanis (Arciero), which shows select Punjabi populations began to genetically diverge from each other about 70 generations (1500-2,000 years) ago. He compares this to a previous study on Indians (Moorjani), which he claims also shows population divergence around 2000 years ago. His reasoning; the fact that the caste-based endogamy structure that crystallized in Hindu-India also appears in Punjab around the same time, is evidence of a shared cultural (Hindu) milieu between the two.
I immediately pointed out a few problems with his analysis:
Firstly, that while the British paper does indeed claim that Punjabi population divergence began as early as 2,000 years ago, it also showed that most of the Punjabi populations did not diverge from each other until 870–1,740 years ago, (with 1,300 being the average)¹. That’s several centuries after the alleged period of caste-crystallization in India, placing us not in the Hindu-renaissance period of the early Guptas², but the Hunnic-Shahi period of Punjab, an era characterized by severe persecution of the Buddhist population³.
Secondly, the Moorjani paper he links (which uses ANI/ASI mixture dating to map India’s transition to endogamy), shows mainland Indians stopped mixing between 1,900–4200 years ago. For comparison, the Kashmiri Brahmins (related to neighboring Punjabi Brahmins) stopped mixing nearly 3,000 years ago. This implies that caste had already come to Punjab (likely during the early Vedic period), but aside from the traditional Hindu groups (like Brahmins), it had been rejected by most of the population.
The following is the polite part of Razib’s response, “you are comparing the period of admixture and formation of the cline vs. the period when endogamy kicks in. these are two separate things. the emergence of caste formation is a separate issue than the emergence of the admixture cline. priya dates the emergence of caste endogamy to the guptas. do the math…”
Razib apparently feels that the cessation of admixture in populations is not the same as the beginning of endogamy. This seems counter-intuitive, but who knows, he is the geneticist after all. The problem however, is that other geneticists (including the one he cites) do equate the end of admixing with the beginning of endogamy. First, from the very Moorjani paper he references:
“These results show that India experienced a demographic transformation several thousand years ago, from a region in which major population mixture was common to one in which mixture even between closely related groups became rare because of a shift to endogamy…
“The period of around 1,900–4,200 years BP was a time of profound change in India…The shift from widespread mixture to strict endogamy that we document is mirrored in ancient Indian texts”
The Moorjani paper explicitly equates their admixture findings (ceasing around 2000 years ago), with the beginning of endogamy. There is no mention of a significant “in-between” period, or method for arriving at the “real” period of endogamy. I think Razib probably realized this, because instead of citing the portion of the paper that rebuts my argument, he leaves us with this gem, “i know this because she told me to my face”.
One of three things are happening. (1): there is confusion from Razib, Moorjani, or both of them, on the timeline of the Guptas. (2): Moorjani sees Indian history through a certain ideological frame, which while typically at odds with the science (hence often left out of papers), is often “leaked” in unofficial capacities⁴ (in this case to Razib’s face). (3): Razib was caught and is desperately trying to save himself (unlikely I believe).
A principal paper referenced in the Arciero study (Basu) also agrees with my interpretation of the Moorjani study, flatly stating, “Earlier genetic studies (Moorjani) have also argued that India was a ‘relatively’ pan-mixing society that embraced endogamy between 1,900 and 4,200 years ago”.
The Basu Paper
Interestingly, the Arciero paper makes an argument similar to Razib’s, that the latter seems to have missed. They instead however cite a more recent paper as their source (Basu, 2016), rather than Razib’s Moorjani (2013). There‘s some confusion regarding the data they present, so I figured I’d tackle it here.
The Arciero paper states, “Our analyses suggest that these subgroups (Punjabis) come from a common ancestral population but diverged from one another within
the last 70 generations (1,500–2,000 years). This is consistent with an earlier
finding (Basu) that the transition from intermarriage to strict endogamy on the Indian subcontinent started from about 70 generations ago.”
Strange. Moorjani found that caste had crystallized in India between 65–145 generations ago (1900–4200 years ago), yet per Arciero, Basu found this process only started about 70 generations ago. Would this not indicate that endogamy in Punjab and India began around the same time? It might, if Basu had actually found that.
Per the Basu paper, “Analysis of ancestral haplotype blocks revealed that extant mainland populations (i) admixed widely irrespective of ancestry, although admixtures between populations was not always symmetric, and (ii) this practice was rapidly replaced by endogamy about 70 generations ago, among upper castes and Indo-European speakers predominantly.”
So the Basu results for North Indians agree with the Moorjani timeline of caste-endogamy crystallizing about 70 generations ago. What about the South Indians and Tribals, which are described as, “temporally less uniform”? The trick is that Basu structured their study to detect not just ANI/ASI admixing like Moorjani, but Australoid/Tibetan as well. Meaning, certain Dalits/Tribals which didn’t register later admixing in the Moorjani study, were shown to be admixing after the 70 generation date by the Basu method.
These tribal populations however were geographically and culturally isolated from the greater Indo-Gangetic plain, which is why Basu does not consider their results to adversely affect his theory (shared by Moorjani), that Indian, “gene flow ended abruptly with the defining imposition of some social values and norms”, during, “the reign of the ardent Hindu Gupta rulers” roughly 70 generations (2,000 years) ago. The only caveat being that Basu believes (and I agree) that such caste-endogamy spread to South India a few centuries later, while the Moorjani study, due to its choice of samples and admix techniques, did not observe such a phenomenon.
Razib Khan believes Punjabis and Indians were traditionally part of the same cultural “Hindu” milieu, based on his reading of select genetic studies, which allegedly show that Punjabis and neighboring Indians developed endogamy around the same time (2000 years ago), in the setting of the Gupta Empire’s expansion.
He is probably wrong. While the above studies have shown that North Indians (Uttar Pradesh, Gujarat) developed caste-endogamy around 2000 years ago, the specific study he refers to (Arciero) shows that most Punjabis became endogamous several centuries after that period. That these two populations diverged so significantly in their development of endogamy, despite being Indo-Aryan neighbors under the Guptas, is a strong point against Razib’s hypothesis (itself based on a misread of the data).
Razib is not the only one to have misinterpreted the data. The Arciero study appears to have misinterpreted the earlier Basu study, as the former mistakenly attempted to tie the isolated Austronesian/Tibetan admixing among Southern-Tribals in the post-2000 ybp period, with the development of endogamy in Punjab during a similar time frame.
Now that I’ve cleared up what the genetic studies say (or rather don’t say) about the Hindu mileu in Punjab, the next step will be to marshal the textual evidence in support of my thesis. Namely, that the Indus Valley⁵ was traditionally estranged from the Gangetic Basin⁶, both politically and culturally, which resulted in the former region never becoming properly Hinducized.
To be clear, I think there was a period when Hinduism began to take hold in Punjab, particularly in the North during the Hunnic-Shahi period (which is supported by the Arciero findings). The bulk of the Punjab however, being semi-nomadic pastoralists, were largely unaffected by what was a principally ubran-cultivator phenomenon. I’ll hope to have this article up in the coming weeks.
I typically enjoy Razib’s work and have learned a lot by reading him, but the personal attacks against me were a bit much. One can have mild academic disagreements with someone, without resorting to calling them, “dumb”, “stupid”, “deceptive”, “delusional”, “sophist”, etc.
Fine-scale population structure and demographic history of British Pakistanis, Arciero 2020.
Genomic reconstruction of the history of extant populations of India reveals five distinct ancestral components and a complex structure, Basu, 2016.
Genetic Evidence for Recent Population Mixture in India, Moorjani, 2013.
0: See the comments here for the Mahabharata excerpts and here for the Vedic excerpts. See the Baudhayana Dharmasutra (P1,A1,K2), where Punjab and Sindh are described as outside Aryavarta (where Hindu customs are observed).
1: The Arciero paper specifies generations (30–60, 45 as an average), and these are converted to “years before the present” (ybp) by multiplying by 29. This is a common conversion figure used by geneticists, though some use different figures, which can result in mildly different ybp values depending on the author.
2: The Gupta reign (345–590 AD) is considered to be a golden age of Hinduism, particularly in North India. Naturally, many Indian authors are eager to tie the development of caste (a central tenant of Hindu culture) to this period, and though most of the North Indian endogamy results appear a bit earlier than the Gupta period, I don’t think this is an unreasonable connection to make.
3: The Hunnic-Shahi period (460–1020 AD) saw the advance of Hinduism in Punjab, Kashmir, and Afghanistan following heavy persecution of the local Buddhists (see The Great Tang Dynasty Record of the Western Regions, Rongxi and Buddhism in North-western India and Eastern Afghanistan, Sixth to Ninth Century AD, Verardi).
4: Despite contributing to papers that help confirm the Aryan Migration Theory, certain Indian authors like Shinde and Rai harbor sympathies for the Out of India Conspiracy Theory, and have given interviews where they will read their personal ideology into the research, in ways they could not in the actual paper. This could be analogous to the alleged conversations Razib is having with Indian authors, that appear to contradict the published data.
5: This region includes Sindh, Punjab, and parts of Baluchistan and Kyber Pakhtunkwa. One could possibly include Kashmir here as well.
6: This region includes Haryana, Uttar Pradesh, Madhya Pradesh, and Eastern Rajasthan and Gujarat. Bihar could arguably be included as well.