The differentiation of the four main components seems clear enough on the figure (left). The big question is how and in what order the different components got into India. I would wager that ASI was first and I modify my New Year's wish to ask for some ancient DNA from India too.
An interesting bit from the paper:
...that the practice of endogamy was established almost simultaneously, possibly by decree of the rulers, in upper-caste populations of all geographical regions, about 70 generations before present, probably during the reign (319–550 CE) of the ardent Hindu Gupta rulersHow plausible is that to anyone familiar with Indian history?
PNAS doi: 10.1073/pnas.1513197113
Genomic reconstruction of the history of extant populations of India reveals five distinct ancestral components and a complex structure
Analabha Basu, Neeta Sarkar-Roya, and Partha P. Majumder
India, occupying the center stage of Paleolithic and Neolithic migrations, has been underrepresented in genome-wide studies of variation. Systematic analysis of genome-wide data, using multiple robust statistical methods, on (i) 367 unrelated individuals drawn from 18 mainland and 2 island (Andaman and Nicobar Islands) populations selected to represent geographic, linguistic, and ethnic diversities, and (ii) individuals from populations represented in the Human Genome Diversity Panel (HGDP), reveal four major ancestries in mainland India. This contrasts with an earlier inference of two ancestries based on limited population sampling. A distinct ancestry of the populations of Andaman archipelago was identified and found to be coancestral to Oceanic populations. 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. This estimated time coincides with the historical period of formulation and adoption of sociocultural norms restricting intermarriage in large social strata. A similar replacement observed among tribal populations was temporally less uniform.
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