But if BB's coming from Steppe through central europe, cohabited with local BB's / local Iberians. How to explain the shift, both in Iberia and the British Islands of y-dna? What kind of social pressure could have been on local men to completely disappear? I mean it's certainly not a coincidence that everywhere where R1a and R1b went, they became dominant? Is it really just nature? Where they physically monsters comparing to their local opponents? Now why did that happened in British Islands, Continental Europe, Eastern Europe and India, but not in Greece and Anatolia? R1b is still the dominant y-dna in modern Greece, modern Armenia and the second after J in Anatolia. So what can explain this, but sample bias? The Greek guy from Empuries probably did spoke Greek, but his genetic is clearly of local Peloponnese-Minoan origin, without Steppe input.