There are some awesome PCA maps in this preprint about dental traits among Europeans and Asians. Below you can see the map based on the first PC, which mainly shows West vs. East Eurasian influence, and closely correlates with results obtained with high density, genome-wide genetic markers. The other maps are more cryptic in what they show (and unfortunately so is the text in this paper which attempts to explain them).
On the base of advantages in gene geography and anthropophenetics the phenogeographical method for anthropological research is initiated and experienced using dental data. Statistical and cartographical analyses are provided for 498 living Eurasian populations. Mapping principal components supplied evidence for the phene pool structure in Eurasian populations and for reconstructions of our species history on the continent. The longitudinal variability seems to be the most important regularity revealed by principal components analysis (PCA) and mapping proving the division of the whole area into western and eastern main provinces. So, the most ancient scenario in the history of Eurasian populations was developing from two perspective dierent groups: western group related to ancient populations of West Asia and the eastern one rooted by ancestry in South and/or East Asia. In spite of the enormous territory and the revealed divergence the populations of the continent have undergone wide scale and intensive time-space interaction. Many details in the revealed landscapes could be backgrounded to different historical events. The most amazing results are obtained for proving migrations and assimilation as two essential phenomena in Eurasian history: the wide spread of the western combination through the whole continent till the Pacific coastline and the envision of the movement of the paradox combinations of eastern and western markers from South or Central Asia to the east and to the west. Taking into account that no additional eastern combinations in the total variation in Asian groups have been found but mixed or western markers’ sets and that eastern dental characteristics are traced in Asia since Homo erectus, the assumption is made in favour of the hetero-level assimilation in the Eastern province and of net-like evolution of our species.
V. F. Kashibadze et al., Reconstructions in human history by mapping dental markers in living Eurasian populations, Submitted on 17 Jul 2011, arXiv:1107.3319v1 [q-bio.PE]
David Reich et al., Reconstructing Native American population history, Nature, Year published: (2012), DOI: doi:10.1038/nature11258