A few weeks ago when I posted on the results of a high likelihood of a partially eastern origin for the Mundari people I received a message via Facebook that the article really wasn't relevant to most South Asians, since only 1-2% spoke a Mundari language (along with pointers to old out of date articles). I immediately replied that it is likely that the Mundari were one of the base populations from which the Indo-Aryan speaking peoples of Bengal, Orissa and Assam arose. The Santals are present as a minority in all three of these states, and the likelihood is that Santal tribals were assimilated into the Hindu (and later Muslim) society, not the other way around. My interlocutor was a little too fixated on issues having to do with colonialism to see clearly what I was trying to get at. That's fine, we all have our own experiences. But in any case the bigger point of that post was to emphasize the importance of representativeness. This is something that really stands out with South Asians. There are around 1.3 billion of us, but the HGDP sample has only Pakistani groups. Some of these, such as the Kalash and Burusho are cultural isolates, whose sampling was justified on the grounds that these people were likely going to be assimilated in the near future. Of the HGDP South Asians only one, the Sindhi, are Indo-Aryan speakers, the language family which covers about ~80% of South Asians. More recentpapers have moderately rectified that situation. Though as a Indian American Bengali friend of mine observed, "there are 200 million of us!" I believe, and hope, in three years that these sorts of worries and questions will seem like ancient history. Below the fold I've taken Dienekes ADMIXTURE estimates for HGDP and HapMap3 South Asian groups and appended myself to them.
I'm soon going to get my parents tested via 23andMe, and I'll have a better sense of my elevated "East Asian" ancestry is due to recent admixture, or part of the normal range in eastern Bengal. If, as I suspect, most of the East Asian is from my father I'll increase the probability of the former. If it's more balanced I'll increase the likelihood that I'm representative of many Bengalis. There are a few Bengalis on 23andMe and most of them have elevated "Asian" ancestry, though not as much as me.