July 14, 2015

Montenegro was part of the Dolmenic Megalithic phenomenon

Just read a most interesting article, with many beautiful images at Old European culture blog: the excavation of a tumulus at Danilovgrad showed it was not a Bronze Age Indoeuropean/Kurgan thing but a true dolmen (trilithon) and many centuries older than expected: c. 2400 BCE. 

There are thousands of similar tumuli awaiting excavation, most in the same rich area of Central Montenegro. This finding puts the Balcanic country (and probably also neighboring regions of the Western Balcans) fully within the Dolmenic Megalithic tradition in the late Copper Age. 

Also an intriguing bronze artifact was part of the grave goods, as well as zig-zag decorated pottery.

July 8, 2015

Zipf's law against 'Genghis Khan' sensationalism

Very interesting new short paper at BioRxiv:

Elsa G. Guillot & Murray P. Cox, High Frequency Haplotypes are Expected Events, not Historical Figures. BioRxiv 2015 (pre-pub, freely accessible) → LINK [doi: http://dx.doi.org/10.1101/022160]


Cultural transmission of reproductive success states that successful men have more children and pass this greater fecundity to their offspring. Balaresque and colleagues found high frequency haplotypes in a Central Asian Y chromosome dataset, which they attribute to cultural transmission of reproductive success by prominent historical men, including Genghis Khan. Using coalescent simulation, we show that these high frequency haplotypes are expected simply by chance. Hence, an explanation invoking cultural transmission of reproductive success is statistically unnecessary.

Not surprisingly it is, once again, the hyper-sensationalist, hyper-recentist, over-simplifying and evidence cherry-picker geneticist Patricia Balaresque who is the object of these very legitimate criticisms.

The basic argument is very simple: in neutrality conditions haplotype distributions follow Zipf's power law, while a single-founder effect of the type of the alleged Genghis Khan one would never cause that: one lineage would be outstanding, while the rest would show no hierarchy. 

However the authors, to make their argument even more certain, simulated genetic data under the standard coalescent, a neutral model that does not include cultural transmission of reproductive success. As you can expect, the simulations confirmed that what surprised Balaresque and others is just absolutely normal by mere chance: no Genghis Khan effect ever took place.