Seeing language from the DNA

[Jaska]

There is a widespread belief among laymen that language could be seen from the DNA. Strangely, they usually angrily deny that accusation, when at the same time they apply a method which cannot work unless they see language from the DNA. Here is a real-life example and my reply to it.

Random blogger:
“N-L1026 is very useful because it can be used to track the Uralic expansion from Siberia to the west, not to predict who currently speaks Uralic.”

The end of your sentence is important, because there are too much erroneous black-and-white beliefs about the interdependence of the language and the DNA. However, the truth that one cannot see the language from the DNA at the present also prevents one from seeing the language from the DNA in the past. All you can see is the expansion of N-L1026 from Siberia to the west, but you cannot just arbitrarily put linguistic label on it.

We have no certainty about the paternal lineages of the population speaking Late Proto-Uralic. The only scientific way for tryingto find them out involves this procedure:

1. We take the linguistic results as the starting point: when and where was Late Proto-Uralic spoken?

2. We look at the genetic data in the relevant spatio-temporal coordinates: what is present there is a tentative genetic correlate for Late Proto-Uralic.

3. Spatial or temporal match alone is not enough, but they must coexist. There have occurred migrations in all times, and the spread of N-L1026 could be either (1) earlier, (2) simultaneous, or (3) later than the expansion of Late Proto-Uralic. The situation where N-L1026 partially overlaps the modern region of the Uralic language family cannot testify that their expansions were simultaneous, not to speak of proving that their expansions were causally related to each other.

For some reason you do not follow the scientific procedure. Instead, you just randomly decide that the expansion of N-L1026 must be associated with the Uralic expansion. Then, based on this dice-roll, you claim that the linguistic evidence can now be ignored and the Uralic homeland can be located based on the DNA, because by some mystical skill you can see the language directly from the DNA. 

Hungarians are an important example about how ancestry of the language carriers changes through time, even in the same region. Ancient Hungarians still had a portion of Siberian (Yakutia_LNBA) autosomal ancestry, but modern Hungarians do not have it. Similar ancestry changes obviously have occurred also during the prehistoric times. Also, during every successive step of a linguistic expansion, it is likely that the genetic composition of the language carriers changes, because assimilation and language shift of earlier population are normal part of linguistic expansion.

This is just one of the many facts that demonstrate us why we cannot see the language from the DNA:
- The Uralic language can remain even when the Yakutia ancestry disappears.
- The Yakutia ancestry can remain even when language shifts: this ancestry is present in populations representing several language families, and we cannot see from the DNA which language the carriers of this ancestry originally spoke.

P.S. In case of trolls, please inform the administrators, so that this thread would not be closed due to insult wars.