The empty heartland

By Razib Khan | September 18, 2010 11:34 am

800px-Two-point-equidistant-asiaIn a comment below I alluded to my idea that the heart of Eurasia was relatively unpopulated before the Holocene, explaining why many Central Asian groups seem to be recent hybrids from very distinct populations. Normally the sort of model which posits K ancestral groups is an idealization to some extent. To assign every K to a real known ancient population is probably not tenable in most cases. Not so for many Central Asian groups, for the K’s often seem rather clear and distinct, and we have a fair amount of historical pointers. Thanks to Herodotus, the early Han dynasty chroniclers, and the Avesta, we have some sense of what the ethnography of Central Asia was like several thousand years ago. Additionally, it seems possible that highly advanced societies such as that of Bactria-Margiana were transferred from elsewhere. The heart of Eurasia may have been to a great extent a thinly populated frontier before the dawn of civilization, and so presaged our own “New World.” But whereas the caravel opened up the trans-oceanic lanes, I assume that in Inner Asia it was the horse which allowed populations to cross the great waterless wastes efficiently enough that trade and people could flow robustly between the oases.

The analogy between Inner Asia and the New World came to me when rereading Haplotype-Sharing Analysis Showing Uyghurs Are Unlikely Genetic Donors. Figure 2 shows “haplotype sharing” between various populations. The left panels compare Uyghurs to their putative parental populations, and the right panels African Americans. Observe how few “private haplotypes” the two populations which came out of a recent admixture have proportionally. The first shaded region in each panel are the private haplotype proportions, while the last shows haplotypes which span all three populations. The two intermediate regions are pairwise comparisons with the ancestral groups.


MORE ABOUT: Heartland, History
  • Georg

    I assume that in Inner Asia it was the horse which allowed populations to cross the great waterless wastes efficiently enough that trade and people could flow robustly between the oases.

    Hello Razib,
    small correction: not the horse per se, but development of
    saddles and stirrups started the traffic in inner asia.
    Taming of Camels may was of importance as well?
    Horses were used to drag carriages for about 1000 years,
    before riding horseback was “invented”.

  • bioIgnoramus

    caraval = feline
    caravel = marine

  • Lab Lemming

    Prior to the holocene, the climate would have been different as well- for example, when China’s now fertile Loess tablelands were active dune fields, the going would have been rougher. Central Asia would have been extremely dry during the ice age- after all, Siberia was too dry to form ice caps.

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About Razib Khan

I have degrees in biology and biochemistry, a passion for genetics, history, and philosophy, and shrimp is my favorite food. In relation to nationality I'm a American Northwesterner, in politics I'm a reactionary, and as for religion I have none (I'm an atheist). If you want to know more, see the links at


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