Failure to replicate sex bias in steppe migrations

"Blnd Dinlin race" ? I was not aware of this, interesting - for the remnant of the extract, we have more data about these roughly said 'cromagnoid' types of Steppes and the opinions are more nuanced -
 
Tomenable said:
About Afanasievo, Andronovo, etc. phenotypes. Oshanin L. V., Antropological Composition of the population of Central Asia, and ethnogenesis of its peoples, 1964:

10. PEOPLES OF CENTRAL ASIA.
the Origin of the brachycephalic Europoid type remains unclear.
Click to expand...
Click to expand...

I hope we go deeply to know where the bronze cromagnoid people (first IE speaker) came from, not just to focus upon the general concept of “Europoid.”

1. Where and how did afanasievo people come from? The anthro and archaeological data of Karzarstan and western steppe of south siberia do not allow west to connect to east at early Bronze age. And afanasievo people were just migrants to the territory of the local okunevo people, being mixed. Later they disappeared and okunevo age started again. How can the afanasievo people claim their terriory in there at that time? They were not invaders and we did not know who were the rulers. Moreover the Afanasievo people was surrounded by such a people like intermediate between mongoloid and europoid. What is relationship between the afanasievo caucasoid and the intermediates? How come afansievo culture merged with the intermediate people’s culture? Did they do with neolithic farmers also in pontic steppe?

http://www.eupedia.com/forum/thread...o-European-history-they-are-just-paleo-people

2. How come Andronovo people face was lower and wider than afanasievo people? How is it possible regardless of their genetic admixture? They have admixtures of yamna and “EEF”, not mongolids.

Neolithic.png


Due to the special facial traits, smart Debets and the other russian anthropologist(2011) mentioned that andronovo people originated in the isolated area of Karzarstan, even if they did not prove it.

http://www.eupedia.com/forum/thread...olithic-to-Bronze-Age-Baikal-Hunter-Gatherers (10)

And it means, I think, their yellow genes would not come from yamna or afanasievo. I think modern genetics still does not clarify the gene of source population. I got the same impression from the recent scythian research that east scythian has component of yamna, not okunevo.
Moreover andronovo(Fedorovo) culture started in East Karzarstan, which is closely related with Indo-Aryan culture. (The Origin of the Indo-Iranians (p252, 2006)- Elena Efimovna Kuzʹmina)
 
Can you guys please take this discussion over to the anthropology section as Moesan suggested at one point? I think there's a thread open there.
 
Andronovo broader faced than Afanasyevo broad faced people? Maybe no surprise: all these descriptions are without any cifer or mean or index, only "digest" notions for amateurs like us; a way to keep his knowledge for himself? I dont know... to understand and compare something we uneed individuals and collective data, with curves and graphics - In my mind the mean types pop they call vaguely 'proto-europoids croma' or the same stuff is a mix where dominate at least two old types, as a whole broader faced than the modern 'europoid' mean(s), one more than the other all the way and in this mean some element(s) with narrower face is/are playing a role, even if light enough - so Andronovo could be 1- Afanasyevo mix + something 'north' broader faced (1a: pre-euro/pre-mongoloid - 1b: pure 'europoid' from where?), or 2- a local drift of the same Afanasyevo mix where the broader faces catched more weight by hazard and? But not only they had broader faces, but also broader skulls (Ceph-index): it could favour the solution 1 - some true brachy's at individual level were found in Steppes -
seemingly the complex subdolicho-very broad faces+subdolicho-rather broad faces (very broad cheekbones) - came from West to East (with post-Maglemose cultures) along the Sth shores of the Baltic Sea towards Nth Russia where they met dolicho-narrow faces (post-Sviderian cult-?) people in the Oka-Volga region, if I red well - but where were the sub-brachy's at this time?

&: beside: what is your Kazarstan? Kazakhstan or?
 
They insist that there is no failure to replicate sex bias:

http://biorxiv.org/content/early/2017/04/03/122218

"Reply To Lazaridis And Reich: Robust Model-Based Inference Of Male-Biased Admixture During Bronze Age Migration From The Pontic-Caspian Steppe"

Amy Goldberg, Torsten Gunther, Noah A Rosenberg, Mattias Jakobsson

Abstract:

Comparing the sex-specifically inherited X chromosome to the autosomes in ancient genetic samples, we (1) studied sex-specific admixture for two prehistoric migrations. For each migration, we used several admixture estimation procedures, including ADMIXTURE model-based clustering (2), comparing X-chromosomal and autosomal ancestry in contemporaneous Central Europeans, interpreting greater admixture from the migrating population on the autosomes as male-biased migration. For migration into late Neolithic/Bronze Age Central Europeans (BA) from the Pontic-Caspian steppe (SP), we inferred male-biased admixture at 5-14 males per migrating female. Lazaridis & Reich (3) contest this male-biased migration claim. For simulated individuals, they claim that ADMIXTURE provides biased X-chromosomal ancestry estimates. They argue that if the bias is taken into account, then X-chromosomal steppe ancestry is similar to our autosomal ancestry estimate, and that hence, steppe male and female contributions are similar. We conduct simulations of ancient and modern data under a range of conditions. We conclude that our inference of male-biased Pontic-Caspian steppe migration, seen using ADMIXTURE, STRUCTURE, mechanistic simulations, and X/autosomal FST, is robust. Our analysis further illuminates the impact of small haploid reference samples on ADMIXTURE; we look forward to refining sex-specific migration estimates as larger, higher-coverage ancient samples become available.
 
Goldberg et al. (2017) originally inferred male-biased admixture at 5-14 males per migrating female, which was lowered to 4-7 migrating steppe males per female in the reply to Lazaridis & Reich. Figure 1 plots estimated X-chromosomal ancestry for simulated BA individuals, which clearly shows substantial male excess during the steppe migration, even though the level of male excess is just half as much as they initially claimed.

image.png

Figure 1.
ADMIXTURE inference in simulated ancient genomes.
 
I wonder if this will go a third round? :)

Quite a reduction as you say, anyway, by about a half.
 
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