Some of the reaction to the finding that Etruscans were not genetically from Romans (Latins) despite being culturally quite different perplexes me. To review, Etruscans clearly spoke a non-Indo-European language and probably were the late-stage development of indigenous Mediterranean farming societies that date back to the early Neolithic. I said this in my Substack piece from March. Yes, I was going off a few samples, but the last ten years have taught us that usually (though not always) a few samples are sufficient.

We have precedence for Indo-European (“steppe”) gene flow does not always lead to cultural transformation. The Basques have mostly Indo-European Y chromosomes, and a lot of steppe ancestry, but retain their non-Indo-European language. Why? Well, one hypothesis is that the Basques were matrilineal (reported by some ancient sources), so Indo-European men assimilated to the clans into which they married.

But we don’t need a detailed or specific explanation. We just need to consider that genes and “memes” flow and transmit differently. Imagine a stylized model where large numbers of Indo-Europeans from Central Europe, with ultimate steppe ancestry, move into the Italian peninsula after 2000 BC. In most cases, they triggered language-shift as they overwhelmed native Neolithic societies. But in Etruria, or what became Etruria, they did not. Even if these Indo-Europeans didn’t invade Etruria, one can imagine a situation where continuous gene flow over the generations would reduce the differences between the two groups. It is quite possible, looking at the assimilation of Roman patrician clans with non-Latin origins (the Claudii were Sabines), that Indo-European speaking clans were assimilated into the proto-Etruscan confederacy and vice versa. You need extremely strong cultural barriers to prevent gene flow between groups.

Culture is not like this. Language and religion do not necessarily even pass down from parents, and it can definitely pass down asymmetrically. The Etruscan language could maintain its continuity in the face of gene flow every generation. There’s no mystery here.