European ancestry is qpAdm's home fixture: the model class the method was literally introduced to defend in 2015, rerun thousands of times since, with the best-sampled sources in the entire ancient record. That maturity makes it the right first recipe — the version of the method where the choices are settled enough to state as a table and the failure modes are all known by name. Here is the standard distal model, why each piece is what it is, and how to adapt it without breaking it.
The three streams#
Present-day Europeans decompose, to first order, into three deeply divergent ancestries that met between roughly 6000 and 2000 BCE:
- Western Hunter-Gatherers (WHG) — the Mesolithic foragers of post-glacial Europe.
- Early European Farmers (EEF) — Neolithic migrants whose ancestry traces to northwest Anatolia, carrying agriculture into Europe from ~6500 BCE.
- Steppe pastoralists — Bronze Age herders of the Pontic-Caspian steppe (themselves a roughly even EHG–CHG mixture, which matters below), expanding west from ~3000 BCE.
The standard distal recipe#
Left (target + sources): the target, plus Turkey_N (Barcın Neolithic, the standard EEF
proxy), WHG (Loschbour/Villabruna-cluster individuals), and Russia_Samara_EBA_Yamnaya (the
canonical steppe proxy). All three predate every living European —
distal by construction.
Right (outgroups): the O9 spine —
Mbuti.DG, Ami.DG, Basque (or another O9 member per the published variant), Onge.DG,
Ust_Ishim.DG, Mota.DG, MA1, Villabruna*, Vestonice16, ElMiron, Ethiopia_4500BP —
with the era contrasts that give the model its discrimination: Russia_EHG and Georgia_CHG (or
Iran_GanjDareh_N) to split steppe from farmer ancestry, Levant_N to pin the southern edge.
(*Villabruna sits on the right only when WHG is proxied by other individuals — the
never-cladal-with-a-source rule; swap it out
if your WHG label contains it.)
Run lowest rank first: two-source EEF+steppe often passes for southern targets where WHG rides inside both sources' backgrounds; admit the third stream when the rank test demands it.
What to expect, calibrated#
The published gradients are your sanity check: steppe ancestry is at a maximum in the Baltic and Ireland/Scotland/Norway (~50%), EEF at a maximum in Sardinia (~70–80%) and the Mediterranean, WHG everywhere the smallest fraction — at its peak in the Baltic — and essentially every value between 30–50% steppe / 30–60% EEF / 5–20% WHG occurs somewhere on the map. A first result far outside those envelopes is a pipeline question before it is a discovery.
The named failure modes#
- The southeast fourth stream. Aegean, Balkan, Italian and Jewish-diaspora targets routinely
reject the three-source model — correctly — because post-Neolithic Near Eastern ancestry
(Anatolia_BA/Levant_BA-related) is real there. The fix is a fourth source or
a proximal reframe, not right-set surgery. The same applies
to Iberian targets with recent North African ancestry (add
Morocco_Iberomaurusian-related or a proximal Maghreb source). - Steppe/farmer collinearity. Yamnaya's CHG half overlaps Iranian-plateau ancestry: with a weak right set the model wanders, SEs balloon, and northeast targets can flip between EHG-flavoured solutions. The EHG/CHG right-set members above are the cure — present because of this failure mode.
- The Finnish/Baltic east. Uralic-associated Siberian ancestry (Nganasan-related) enters late in the northeast; three-source models of Finns, Estonians and Saami-admixed targets fail until a fourth Siberian source is admitted.
- Umbrella-label WHG.
WHGin the AADR pools individuals from Iberia to the Balkans across millennia; check the .anno file and prefer a tight cluster for source duty.
A worked reading#
A concrete pass, from our own report format: an Irish-ancestry target, p = 0.31, Yamnaya 0.48 ± 0.021, Turkey_N 0.38 ± 0.024, WHG 0.14 ± 0.018 — all weights more than 2 SE from 0 and 1, both nested two-source models rejected below p = 0.01, ~710k SNPs used. Reading: compatible, well-determined, literature-consonant (high-steppe northwest edge), and the nested rejections certify all three streams are required, not decorative. That last line — the one no percentage bar chart can utter — is what the method is for.
Terms used here are defined in the glossary.
References#
- Haak, W. et al. (2015). Massive migration from the steppe was a source for Indo-European languages in Europe. Nature, 522, 207–211. (The recipe's debut.)
- Lazaridis, I. et al. (2016). Genomic insights into the origin of farming in the ancient Near East. Nature, 536, 419–424. (O9 and the distal framework.)
- Mathieson, I. et al. (2018). The genomic history of southeastern Europe. Nature, 555, 197–203. (Regional variation and the Balkan fourth stream.)
- Patterson, N. et al. (2022). Large-scale migration into Britain during the Middle to Late Bronze Age. Nature, 601, 588–594. (Modern-era refinements to the same model class.)
