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Unfounded

Posted by Maju on 19 Nov 2009 at 01:44 GMT

First, the first PCs emphasize the role of migration and dispersal in human history, including: dispersal out of Africa, spread across Eurasia, entry into the Americas, and entry into Oceania. Indeed, the order of the PCs closely corresponds to the relative timing of these events
http://plosone.org/article/info:doi/10.1371/journal.pone.0007888#article1.body1.sec3.sec1.p2

I fail to see any correlation whatsoever between PC1 and any possible timing of colonization that should be (1) South Asia, (2) East Asia and Oceania, (3) West Eurasia and (4) America. PC1 shows a West Eurasian-African axis and PC2 an East Eurasian-African axis, that's all.

No competing interests declared.

Correcting myself

Maju replied to Maju on 19 Nov 2009 at 01:51 GMT

Sorry: the other way around: PC1 means Africa-Pacific genetic distance and PC2 Africa-Europe. Is that what you mean? That the later colonization of West Eurasia in relation to South and East Eurasia is reflected in the relative greater distance represented by PC1 in relation to PC2? I don't gather that from your explanation.

No competing interests declared.