Steppe_EMBA Eatern Hunter-Gatherer (EHG) 0.568 Iran Chalcolithic (Iran_ChL) 0.432 Steppe_EMBA Caucasus Hunter-Gatherer (CHG) 0.181 Eastern Hunter-Gatherer (EHG) 0.527 Iran Chalcolithic (Iran_ChL) 0.292I'm not a huge fan of either of these models, but especially the first one, even though I understand that they're both statistically very sound. For one, the uniparental markers don't match, and two, TreeMix seems to disagree (see here).
Outgroups Anatolia_Neolithic Andamanese_Onge Chukchi Han Israel_Natufian Karitiana Kostenki14 Levant_Neolithic MA1 Mbuti.DG Papuan WHG Steppe_EMBA Anatolia Chalcolithic (Anatolia_ChL) 0.128 Caucasus Hunter-Gatherer (CHG) 0.375 Eastern Hunter-Gatherer (EHG) 0.497As far as I can tell, it's a very decent fit, especially considering that I'm using 12 outgroups and three reference populations. To me, at least, the standard errors look surprisingly low for such a complex model: 0.033, 0.046 and 0.020, respectively. Now, I'm not arguing here that Chalcolithic Anatolia is the answer. What I'm saying is that multiple lines of evidence do not support Chalcolithic Iran as a real source of admixture for Steppe_EMBA, and I'm offering what I see as a plausible alternative among the currently available samples. I know that this is a work in progress for the Broad MIT/Harvard team, and we'll have to wait for more ancient samples and another paper or two before a consensus is reached on the topic. But here's my prediction: Steppe_EMBA only has 10-15% admixture from the post-Mesolithic Near East not including the North Caucasus, and basically all of this comes via female mediated gene flow from farming communities in the Caucasus and perhaps present-day Ukraine.