In ~48 hours I will be recording a podcast with Vagheesh Narasimhan, first author of The formation of human populations in South and Central Asia, and the second author of An Ancient Harappan Genome Lacks Ancestry from Steppe Pastoralists or Iranian Farmers. We’ll have lots to talk about but open to taking questions from readers as well.
As per usual I’ll be posting it for patrons first.
(I’m also recording a podcast with ex-academic Justin Murphy)
Please keep the other posts on topic. Use this for talking about whatever you want to talk about.
At the bottom of this post, I have posted a reformatted version of a table from the supplemental of The Formation of Human Populations in South and Central Asia. It shows a model of three hypothetical ancestral groups which contribute to the variation of modern South Asians:
One of the things that people are doing is looking at “Central_Steppe_MLBA_related” as proxy-for Indo-Aryans. This is not totally wrong…but it is misleading. This fraction to me is indicative of the floor of the contribution of Indo-Aryans into modern Indians. Let me quote from the paper:
We next characterized the 2000 BCE Steppe Cline, represented in our analysis by 117 individuals dating to 1400 BCE – 1700 CE from the Swat and Chitral districts of northernmost South Asia (Fig. 2, Fig. 4). We found that we could jointly model all individuals on the Steppe Cline as a mixture of two sources albeit different from the two sources in the earlier cline. One end is consistent with a point along the Indus Periphery Cline. The other end is consistent with a mixture of about 41% Central_Steppe_MLBA ancestry and 59% from a subgroup of the Indus Periphery Cline with relatively high Iranian farmer-related ancestry ((13), Fig S50).
It seems very likely that a substantial proportion of the ancestry of the Indo-Aryans when they entered Punjab was already mixed with “Iranian-related” ancestry from further north and west. In the table below 13% of the Patel ancestry is from Central_Steppe_MLBA. All of this is from “Indo-Aryans,” but I assume some of the 60% Indus_Periphery_Pool is probably from Indo-Aryans as well.
Continue reading The intrusive Indo-Aryans had a huge demographic impact on South Asia
Some of you are probably not amused by the jokes I try to make about AIT and Lord Indra. I hope it’s pretty clear I’m not serious about all of this…it’s just that people take these issues so seriously.
I’ve changed my mind on the “peopling of India” question several times since I began to take a genetic interest in the topic around the year 2000. That’s because the genetic and archaeogenetic technology and data has gotten better and better with every passing year. We can answer questions with power and precision that we couldn’t even imagine asking a few years ago.
Some of you are asking questions that are already answered in the supplements of the Narasimhan paper. From page 260:
With respect to South Asia, our key finding is that people with ancestry like the Kushan individuals can be excluded as important sources of the Steppe pastoralist-related ancestry that is widespread in South Asia today. In particular, the East Asian-related admixture (via Steppe_LBA ancestors) that characterized the Kushan individuals is nearly absent in South Asia. We formally confirmed this inference through qpAdm modeling that excludes the Kushan individuals, as well as nearly all the other Iron Age and historical period individuals from other cultural contexts that were published in two recent studies (29, 30) as plausible sources for the Steppe pastoralist-related ancestry in South Asia (Fig S 50).
Though culturally and historically significant, like the Muslims, the earlier steppe people that are prominent in Indian history don’t seem to have made a major genetic impact.
The question has been answered. And that’s good.
In the comments below some readers are asking about whether arguments have been won. Knowledge and science proceed through argument. But let me be clear here: I am not invested in a particular outcome, I am haunted by the possibility that we can know the truth of things. As a child, I was fascinated by history, but I always knew that I was going to go into science, because science progresses, while history circles in argumentation. What ancient DNA has done has been to illuminate the darkness of the demographic past. This is not the totality of human history, but it serves to provide a critical and precise scaffold on the questions we ask and the answers we come to.
The American Academy is so ideologically blinkered and biased that I am not going to throw stones any longer when I see people in other nations engaging in this sort of behavior. This is the world we live in. Knowledge is not furthered through institutions in anything more than a proximal manner. The results, the data, are out there. We need to grasp them and interpret them for ourselves. The truth is ours. If we choose to take it.
I’ll update this post as needed.
Update: Rakhighari paper is out, An Ancient Harappan Genome Lacks Ancestry from Steppe Pastoralists or Iranian Farmers.
The graphic abstract gets at the main point:
Update II: The Formation of Human Populations in South and Central Asia. The map says it all:
I did some more data analysis. Added Tibetans, etc. Since some readers have more opinions than I do I’ll leave commentary up to them. Two notes
1) The “Northeast Indian” group includes populations like Mizos (I know that from the ID codes). They seem different from Nagas, who are more Tibetan
2) No idea why Bangladeshis are showing so much “South Chinese” signal in admixture. Perhaps it is artifactual, or, we’re missing some donor population? There is clearly some Munda admixture in a few individuals, but it doesn’t seem to be the dominant contributor of East Asian ancestry.
Hoping for some illuminating comments.
Please keep the other posts on topic. Use this for talking about whatever you want to talk about.
Doing some data analysis for my data job. Looking at the data sets some interesting patterns. I will explore further time permitting, but it looks to me that the Bengalis are on the Khasi/Tibeto-Burman cline, not the Munda cline. Basically, Bangladeshis are the inverse of the Khasi people to their north. After seeing these results I read a bit more on the Khasis, and it’s fascinating to see how some of them look like my relatives in their facial features.
(the Iranians are sampled mostly from the west of the country, explaining their separation from Pakistani samples, which include Pathans)
The podcast from last fall on Indian genetics is probably worth listening to, as you’ll be hearing more about the topic shortly…
Reading a paper on Yemen made me realize something that is quite bizarre upon reflection: the greater the evidence of Islam’s transformative power, the greater the miracle and robustness of Indian religion in the face of its expansion. To me, Islam’s demographic impact is clear when it comes to Sub-Saharan African ancestry. Though some of the admixture into Near Eastern and Mediterranean populations predates the Islamic era, most of it always seems to date to the last 1,000 years.
Whatever the ideological merits of Islam, the Islamic civilization had massive economic, social, and demographic consequences as seen in the genes. It took the culture of Iran and transformed its religion.
Which takes me to India: the more impactful Islam seems to me, the more amazing it is that India remained 75% non-Muslim on the eve of partition. The most Islam-skeptic Indians tend to be pro-Hindu, but historical evidence of Islam’s power and influence actually suggest that Hinduism is something very special as a cultural complex.
Note: I say “Indian religion” to side-step semantic arguments about Hinduism. Ironically, I think modern elite Hinduism probably emerged and developed around the same time as Islam itself, though proto-Hindu beliefs are clearly very old.
Where Does Affirmative Action Leave Asian-Americans?
For the purposes of this article, Alex Chen, an 18-year-old senior at the Bronx High School of Science in New York City, is the “typical Asian student.” Alex has a 98 percent average at one of the city’s elite public high schools, scored a 1,580 on the SAT and, as far as he knows, has earned the respect of his teachers. Alex is also the vice president of technology for the Bronx Science chapter of the National Honor Society, the director of graphics and marketing for TeenHacks L.I. (“the first hackathon for teens in Long Island”), a member of the cross-country team, the vice president of the school’s painting club, the president of the Get Your Life Together club (visitors from various businesses come talk to students) and the senator for his homeroom. In his free time, he plays Pokémon and goes on long jogs through Van Cortlandt Park in the Bronx. His parents, Qiao and Su, emigrated from China in the ’90s and worked their way through commuter colleges in Queens. They live along with Alex’s little brother in a modest apartment in outer Queens….
The piece is very long. It mostly focuses on East Asians for various reasons. But one thing that I think confronts South Asians is that many of us are quite dark-skinned, and though not African American, are more liminal physically to that identity than East Asians. To be entirely frank one perverse, but predictable, aspect of American-style affirmative action is that a dark-skinned South Asian doesn’t obtain the same status and benefits as a white person of Latin American origin.
