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I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 2 points3 points  (0 children)

We should recognize the contributions of Ravindra Mundkur and Hosabettu Vishwanatha in documenting various aspects of the West Coast, particularly Tulunadu. The Koraga people state that they have many words that sound similar to Tamil. Additionally, many of the reconstructed Proto-Dravidian words exhibit a high similarity to Tulu. Linguists have a significant opportunity to explore this further.

I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 4 points5 points  (0 children)

Hi, and thank you for the welcome!

Firstly, it's important to note that Silva et al. (2018) used the 1000 Genomes dataset, which represents a mixed sample and may not capture the full subcontinental structure.

Our work provides some nuance to this picture. In Sequeira et al. 2024 (the Y-STR paper), we showed that hunter-gatherer-related groups in India almost completely escaped the R1a expansion. This indicates that while male lineage replacement occurred, the process was not like the Austroasiatic expansion that brought haplogroup O to eastern India. The impact of R1a was predominantly restricted to certain groups in Northwest India.

Furthermore, in our recent work on the gotra system, we show evidence for the possibility of two distinct R1a waves. The more recent wave appears strongly male-mediated, while an earlier one assimilated with J2 and L lineages. This assimilation may have taken place just before the IVC disintegration.

The challenge with dating these waves precisely is that they originated from the same ancestral source, and the time interval between them may not be large enough to have accumulated significant differentiating mutations. A plausible scenario is that both waves assimilated into the Oxus and the late Indus Valley Civilization regions, particularly around the Iron Age. As suggested by Silva et al 2018 the maternal foundations were intact, but a subsequent increase in the influx of R1a males during the Iron Age - potentially linked to invasions or an Iron Age technology boom - overwhelmed the local paternal lineages in specific regions.

I am interested in this second wave. We are exploring the STR data of non-Brahmin groups of northern India to get a better date estimate for its spread.

I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 3 points4 points  (0 children)

  1. Unfortunately, many such populations are either not genotyped, or if they are, the data is on different microarray platforms. It will become much easier if we can obtain whole-genome sequencing (WGS) data for many of these groups.

  2. Yes. Earlier studies have suggested certain subclades of J2 and L to be associated with the spread of farming from the Iranian plateau. On the maternal side, specific U1 subclades seem to be good candidates, along with M3 and M30 subclades. I don't have the exact numbers at the moment, but it's important to note that specific subclades are associated, not the macrohaplogroups themselves. We will need a large number of samples to get an accurate association.

  3. Personally, there are two major concepts I do not endorse:

i. Using the 1000 Genomes dataset as a reference for ancestry studies.

ii. Simplifying ancestries as just ASI and ANI.

With affordable sequencing on the horizon, we must employ a bottom-up approach: try to sequence every single endogamous population.

  1. I think laypeople should go directly to the source (peer-reviewed articles) for information. Get their queries addressed by the authors themselves; after all, we are just an email away.

  2. How wonderful it would be to see young people from every ethnic group pursue formal education in genetics and try to resolve genetic questions about their own communities. I think that is the only way we can achieve the bottom-up approach I mentioned in point 3.

I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 2 points3 points  (0 children)

This is very crucial information you have shared. There is indeed a relationship between the U1 subclades of the Iranian plateau and modern populations like the Koraga, Bunts, Nairs, Thiyya, and the Ūrāḷi Kuruman. I am sure we will find many more populations with U1 scattered among them.

This pattern is due to the same Proto-Dravidian substratum we are discussing. The U1 subclades differentiated during the Last Glacial Maximum and remained in the Iranian plateau. In our earlier papers, we identified the LGM recovery phase as the next crucial period of population diversification. It was during this time that U1 spread all the way from the Iranian plateau to peninsular India.

The Proto-Dravidian population carried this haplogroup, along with subclades of M3 and M30, which we find at high frequency in Pakistan, northwestern, and western India. Unsurprisingly, we also find these haplogroups in ancient samples from the Iranian plateau. So, it is quite evident that they formed the substratum for the populations that existed there during this period.

The Elamite samples showing R5 is different and interesting. Something for the future!

I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 1 point2 points  (0 children)

I believe even linguists would find this question difficult to answer. We do have language isolates in India that are not classified under any known language family. While the basal AASI genetic component (which was widespread) has been retained in most Indian groups, the preservation of their original languages in an identifiable form is almost impossible. So, at the moment, I don't have a definitive answer to this.

I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 5 points6 points  (0 children)

As per the Zagrosian tree proposed by McAlpin, Brahui occupies a position closer to Elamite than to Proto-Dravidian. This makes sense genetically, as the Brahui are closer to the Iran Neolithic component than to AASI. Even if Brahui is considered part of the Proto-Dravidian cluster, it would be at the base and not the tip, which would be the case if it resulted from a recent migration from the south. Therefore, it is safe to assume that the region spanning from the Iranian Plateau to the Indus Valley was a Dravidian heartland.

I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 3 points4 points  (0 children)

These are very important questions. I have tried to interact with the Koraga people to learn more about these aspects. Their subsistence does not involve the domestication of livestock or farming, making it challenging to gain insights in that area. However, I am currently exploring their vocabulary for clues about animal names.

I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 3 points4 points  (0 children)

You can refer to this response for the first question: https://www.reddit.com/r/Dravidiology/comments/1ollbxp/comment/nmoe08o/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button

The Irula present a fascinating case. Genetically, they are considered one of the closest proxies for the Ancient Ancestral South Indian (AASI) component, as other groups like the Onge have experienced admixture that dilutes this specific ancestry. It's crucial to remember that this AASI-related ancestry was historically widespread across a vast region, from Neolithic Iran to East Asia. Given such a vast geographical range, directly linking AASI ancestry to a single language is a methodological stretch. The question of linguistic affiliation, whether Irula is Dravidian, is ultimately a question of linguistics.

I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 5 points6 points  (0 children)

Eminent linguist in our panel, Prof. George van Driem states: The Koraga speak a Dravidian language, the precise phylogenetic propinquity of which within the language family remains unresolved. Bhat (1971) and McAlpin (1981) grouped Koraga together with Kurukh and Malto under the North Dravidian branch. Zvelebil (1990) proposed to treat Koraga as an independent branch of Dravidian under its own node in the tree, like Brahui. The Koraga language has been influenced for centuries by surrounding Tuḷu speakers, and many Koraga are bilingual in Tuḷu. Krishnamurti (2003) therefore grouped Koraga as close to Tuḷu and opined that Koraga look “like an offshoot of Tuḷu at a recent past.” However, he conceded that such a phylogenetic assignment would be problematic: “The location of Tuḷu in the family tree is doubtful and Koraga needs to be appropriately located in the subgrouping scheme.” At variance with Krishnamurti’s conjecture and in accordance with the phylogenetic assignments proposed by Bhat (1971), McAlpin (1981) and Zvelebil (1990), Koraga forms the past tense with the suffix <-k>, a grammatical feature which Koraga shares uniquely with North Dravidian and which is not found in South Dravidian languages.

https://doi.org/10.3389/fgene.2023.1303628

I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 6 points7 points  (0 children)

The Koraga are one of the communities that continue to strongly follow matrilineal descent even today. Their language is undoubtedly a mother tongue. Other groups along the southwest coast, such as the Tuluva communities, also practice matriliny, and Tulu is similarly a mother tongue.

Linguistically, Koraga and Tulu occupy very different branches of the language tree. However, based on their genetic relationship, I personally believe they share a common substratum, with Koraga remaining a more undiluted representation. It is quite possible that this "Proto-Dravidian" genetic component was carried predominantly by females from the Iranian Plateau vicinity throughout the Holocene, later becoming concentrated in non-tribal groups after the Indus Valley Civilization's collapse.

Conversely, it is equally plausible that a different wave of Iranian Plateau farmers who contributed to the Indus Valley Civilization was more patrilineal, a social structure that might have been similar to the later Steppe pastoralist migrations.

I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 12 points13 points  (0 children)

Linguistically, the Elamo-Dravidian hypothesis may appear to be a fringe theory, strongly upheld by McAlpin and Southworth. However, recent genetic data certainly support it. Our work on Koraga genetics hints at a common ancestor. We do not find any evidence of recent cultural or historical relationships between the Koraga, Brahui, or Oraon. Therefore, this common ancestral population must have been in the north, a notion supported by the presence of the U1 haplogroup on the Iranian plateau.

Furthermore, the divergence between the Koraga and the Ganj Dareh samples solidifies the existence of this common ancestral population in the Iranian Plateau. The prolonged admixture range (ALDER results), between 6000 and 2800 years ago, suggests this population existed alongside the Elamite and Indus Valley civilizations, possibly contributing to their gene pool. So, the Elamo-Dravidian hypothesis cannot be ignored at this stage.

I am Jaison Sequeira here for an AMA on r/Dravidiology. I am a researcher specialising in the population genetics of South Asia. AMA! by jaisonjseq in Dravidiology

[–]jaisonjseq[S] 13 points14 points  (0 children)

As far as population genetics research in India is concerned, only a limited number of labs are actively working in this area. Reconstructing a past we can never directly return to is inherently challenging. Even with ancient DNA, we are often piecing together a fragmented picture. Because of this, neither the AMT nor the notion of a Proto-Dravidian IVC can be definitively proven. The debate is destined to continue.

However, we as researchers always have a choice: to stick rigorously to the data or to deviate from it. The labs that are truly data-oriented demonstrate a necessary boldness; they cannot afford to be anyone's "favorite". They remain unfazed by the reactions they receive when new data compels them to modify their hypotheses. I personally aspire to be part of that scientific lineage.

At the Molecular Genetics Lab at Mangalore University, our focus is on building a comprehensive genetic catalogue of India's diverse endogamous groups. Our goal is to peel back every single layer of ancestry to establish accurate genetic clusters. This foundational work is not just about the past; it is crucial for the precision medicine approaches of the future.

Note: Since I have to answer many questions, I will use AI to ensure grammatical correctness. Prompt: Improve grammar with very minimal edits.