Tuesday, September 1, 2009

Genetics And Aryan Invasion Debate

India’s case Since the 1990s, there have been numerous genetic studies of Indian populations, often reaching apparently divergent conclusions. There are three reasons for this: (1) the Indian region happens to be one of the most diverse and complex in the world, which makes it difficult to interpret the data; (2) early studies relied on too limited samples, of the order of a few dozens, when hundreds or ideally thousands of samples are required for some statistical reliability; (3) some of the early studies fell into the old trap of trying to equate linguistic groups with distinct ethnic entities — a relic of the nineteenth-century erroneous identification between language and race; as a result, a genetic connection between North Indians and Central Asians was automatically taken to confirm an Aryan invasion in the second millennium BCE, disregarding a number of alternative explanations.7 More recent studies, using larger samples and much refined methods of analysis, both at the conceptual level and in the laboratory, have reached very different conclusions (interestingly, some of their authors had earlier gone along with the old Aryan paradigm8). We will summarize here the chief results of nine studies from various Western and Indian Universities, most of them conducted by international teams of biologists, and more than half of them in the last three years; since their papers are complex and technical, what follows is, necessarily, highly simplified and represents only a small part of their content. The first such study dates back to 1999 and was conducted by the Estonian biologist Toomas Kivisild, a pioneer in the field, with fourteen co-authors from various nationalities (including M. J. Bamshad).9 It relied on 550 samples of mtDNA and identified a haplogroup called “U” as indicating a deep connection between Indian and Western-Eurasian populations. However, the authors opted for a very remote separation of the two branches, rather than a recent population movement towards India; in fact, “the subcontinent served as a pathway for eastward migration of modern humans” from Africa, some 40,000 years ago:
“We found an extensive deep late Pleistocene genetic link between contemporary Europeans and Indians, provided by the mtDNA haplogroup U, which encompasses roughly a fifth of mtDNA lineages of both populations. Our estimate for this split [between Europeans and Indians] is close to the suggested time for the peopling of Asia and the first expansion of anatomically modern humans in Eurasia and likely pre-dates their spread to Europe.”
In other words, the timescale posited by the Aryan invasion / migration framework is inadequate, and the genetic affinity between the Indian subcontinent and Europe “should not be interpreted in terms of a recent admixture of western Caucasoids10 with Indians caused by a putative Indo-Aryan invasion 3,000–4,000 years BP.”..READ MORE

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