A paper in
Science co-authored by around 200 scientists from some of the world's top academic institutions surely must mean something, right? Not necessarily.
In this short blog post I'll try to explain, as simply as I can, why the
Lazaridis, Alpaslan-Roodenberg et al. paper doesn't get us any closer to solving the riddle of the so called Indo-Anatolian homeland.
However, it must be said that the paper does include many interesting and valuable samples. I'll be using six of these samples, labeled TUR_C_Gordion_Anc, to argue my case.
The TUR_C_Gordion_Anc sample set is from Gordion, the capital of ancient Phrygia, and thus, in all likeliness, it represents Phrygian speakers.
Phrygian is an Indo-European language and the leading hypothesis is that it originated in the Balkans.
In terms of fine scale ancestry, TUR_C_Gordion_Anc can be reliably divided into two genetic clusters. In the Principal Component Analysis (PCA) below these clusters are labeled TUR_C_Gordion_Anc1 and TUR_C_Gordion_Anc2.
Note that TUR_C_Gordion_Anc1 is obviously pulling away from TUR_C_Gordion_Anc2 towards samples from the Balkans. I've used ancient samples from what is now North Macedonia, labeled MKD_Anc, to represent the Balkans. To see an interactive version of the plot, paste the PCA coordinates from
here into the relevant field
here.
Visually, this is not an especially dramatic outcome, but it's an incredible result nonetheless, because it shows that even a few ancient samples can help to solve an age old mystery.
Across many dimensions of genetic variation, the shift in the PCA from TUR_C_Gordion_Anc1 to TUR_C_Gordion_Anc2 represents about 20% admixture from the Balkans, and about 8% from the Eastern European steppe. That's plenty enough to corroborate the linguistic hypothesis that the Phrygians originated in the Balkans, and that some of their ancestors came from the steppe. The mixture models below were done with the tools
here.
Target: TUR_C_Gordion_Anc1
Distance: 1.6634% / 0.01663373
40.6 Kura-Araxes_ARM_Kaps
22.2 Anatolia_Barcin_N
21.8 MKD_Anc
13.6 Levant_PPNB
1.4 IRN_Ganj_Dareh_N
0.4 Han
Target: TUR_C_Gordion_Anc1
Distance: 1.7109% / 0.01710904
40.2 Kura-Araxes_ARM_Kaps
37.8 Anatolia_Barcin_N
12.4 Levant_PPNB
8.0 Yamnaya_RUS_Samara
1.2 IRN_Ganj_Dareh_N
0.4 Han
Target: TUR_C_Gordion_Anc2
Distance: 2.0293% / 0.02029339
51.0 Kura-Araxes_ARM_Kaps
26.8 Anatolia_Tepecik_Ciftlik_N
17.6 Anatolia_Barcin_N
4.6 Levant_PPNB
Surprisingly, Lazaridis, Alpaslan-Roodenberg et al. didn't have much to say about this topic. This quote basically sums it up:
However, in individuals from Gordion, a Central Anatolian city that was under the control of Hittites before becoming the Phrygian capital and then coming under the control of Persian and Hellenistic rulers, the proportion of Eastern hunter-gatherer ancestry is only ~2%, a tiny fraction for a region controlled by at least four different Indo-European–speaking groups.
I have no doubt that Lazaridis, Alpaslan-Roodenberg et al. can run a very decent PCA, and then blow it up to a size big enough to show that the Gordion samples represent two genetically somewhat distinct groups. I'm also sure that, if they really try, they can locate significant levels of
proximate and relevant European ancestry in some of these samples.
They don't have to use my methods; they can use any methods they like. My point is that they won't find much if they're just looking for genetic signals from the Upper Paleolithic or Mesolithic.
Now, considering the way that the Phrygian question was treated by Lazaridis, Alpaslan-Roodenberg et al., despite the fact that they managed to sequence a few likely Phrygian speakers from none other than the Phrygian capital, let's not pretend that their paper brought us any closer to understanding the genetic origins of Anatolian speakers or pinpointing their ancestral homeland.
In order to even try to solve these problems with ancient DNA, we need a wide range of samples from Hittite, Luwian and other key sites where Anatolian languages were spoken. And then we must analyze them properly.
I'm guessing that Lazaridis, Alpaslan-Roodenberg et al. went out of their way to get such samples, but for one reason or another they failed. If so, that's OK, but I have a feeling that even if they got them, they wouldn't know what to do with them, because at best these samples would only show ~2% Eastern hunter-gatherer ancestry. Haha.
For what it's worth, I believe that the ancient data in the Lazaridis, Alpaslan-Roodenberg et al. paper point to the North Pontic steppe as the Indo-Anatolian homeland, and I'll lay out my arguments in an upcoming blog post.
See also...
Dear Iosif...Yamnaya
Dear Iosif, about that ~2%
Dear Iosif...
Dear Iosif #2
Dear Iosif #3
