People migrate -- they always bring their DNA with them and their language. No? The connections between these have been studied for a long time -- for example, this popular book was published 20 years ago: https://www.ucpress.edu/book/9780520228733/genes-peoples-and...
A nice counter-example is Finnish (and other Finno-Ugric languages) – back in the early 1900s it was argued that Finns as an ethnicity must have originated from the Urals because the language seemed to have its roots there. (Notably in the era's racial "science" this had clear racist implications.) But modern genetics have revealed that the origins of the people are quite separate from the origins of the language.
Indeed this is so, but where does one find further information online (or not online) ? Such a case where language and genetics do not align is unusual in the world, but I have read that there are a few cases. Mostly associated with conquest and/or assimilation IIRC.
Turks are commonly said to be Mediterranean people with a Central Asian language. No clue about how true this is genetically but anecdotally I think Turks look quite similar to Greeks and Italians, and not much to eg Turkmen.
This is very common. The Romans did not genocide and repopulate everywhere they conquered, for example. A lot of romance language speakers genetically contiguous with Celts and other such things.
And going back further there is evidence of genetic continuity with pre-Indo-European European populations too.
The picture with the Indo-Europeans becomes a little clearer when you distinguish between Y-chromosomal and mitochondrial DNA. The genetic continuity with pre-Indo-Europeans is entirely on the mothers’ side; the Y-chromosome DNA of that population was entirely replaced with that of Indo-Europeans.
True but something like this is hard to accomplish without a centralized state or other institution which encourage assimilation.
Prior to that it’s more likely that the invaders killed and/or subjugated most of the mean and put themselves at the top of local hierarchy meaning that they and their descendants were more likely to have successful offspring.
Based on genetics that seems to have been the case in Europe.
But given that Finland's neighboring languages (Swedish & Russian, the languages of the conquerors) are IE, wouldn't one (plausibly) expect to see an IE language atop a non-IE gene pool ? Instead one sees the opposite. So does this mean a strong link (of some sort or another) between Finnish and Saame (Lapp) ?
People can change their language. Hungary and Turkey speak the languages of conquerors who have left very little genetic trace. (France is in a similar position!) Many Ethiopians speak a Semitic language (Amharic) for reasons unknown to us. Yiddish is a Germanic language spoken by a non-Germanic people. The Chinese of Thailand often cannot speak any Chinese (they speak Thai).
I assume the argument here is that if you see a huge linguistic expansion and a huge demographic expansion occurring at the same time, you can reasonably conclude that they are the same phenomenon and the expanding language is spoken by the expanding people. But the language and the people are not in general the same; people may voluntarily adopt a foreign language without moving (compare India and English) and they may fail to bring their language with them when they move. They cannot avoid bringing their DNA with them, but it will die out when they do, which their language may not.
>Many Ethiopians speak a Semitic language (Amharic) for reasons unknown to us.
Amharic isn't the only Semitic language spoken in Ethiopia. We have other Semitic languages spoken both in Ethiopia and Eritrea. It is just the Red Sea that divides these two countries from the other Semitic speaking countries. Yemen, across the sea has other Semitic languages other than Arabic. Also, just like Indo-European is a large grouping of languages, the Semitic languages are ordinarily grouped under Afro-Asiatic languages. Thus, besides some of the Semitic languages spoken in Ethiopia and Eritrea, we also have two other subgroups of Afro-Asiatic namely, Cushitic and Omotic languages that are also spoken in Ethiopia. Amharic thus is well contextualised for Ethiopia.
The fact remains that you would not expect to see black Africans speaking any Afroasiatic language without some kind of significant cultural shock. The reason those languages are in Ethiopia ( / Nigeria / etc. ) today is not that Ethiopia is populated by the descendants of an originally afroasiatic group. Something must have happened.
The Semitic languages are Afroasiatic languages. I agree with your general point but ironically you yourself now try to link language to genetics (skin color).
In the horn of Africa they've always spoken Semitic languages as far as we know, and actually it's possible the entire language family originated in Africa, not in West Asia as I guess you assume. This hasn't been proven one way or another, both theories exist.
Ethopians also just don't really look very much like west African (Niger-Congo speakers, but it is nonsense to presume Ethopians area "hybrid" population while west African Niger-Congo speakers and west Asian Semitic speakers are are "basal".
Niger-Congo does not belong to the Afroasiatic language group. I mentioned Nigeria because of Hausa. Obviously I would no more assume that the Hausa are a basal Afroasiatic group than that any Ethiopian group is.
Nigeria is all the way on the other side of the African content while the Arabian peninsula is right across the very narrow Red Sea. So it would make less sense for Ethiopians to speak a language that’s related to languages spoken thousands of kms away in West Africa than for them to speak a language that’s related to the languages spoken on the other side of the Red Sea - which is exactly what they do.
Edit: also, if you look at pictures of Ethiopians and Eritreans and of Yemenites you’ll see they’re way more similar in appearance than Ethiopians and, say, Nigerians.
Yeah, my wife is Ethiopian and she was shocked to see in TV news coverage how "Ethiopian" a lot of the Houthi rebels in Yemen looked, but this is actually not surprising once you know the histories of the Horn of Africa and Red Sea at a greater detail.
> I assume the argument here is that if you see a huge linguistic expansion and a huge demographic expansion occurring at the same time, you can reasonably conclude that they are the same phenomenon and the expanding language is spoken by the expanding people.
That's a lot to assume, though. One possible counterexample is contemporary North America. The English-speaking population spread across the continent in a linked process, the same phenomenon, but the majority contribution genetically, is not from England. There are communities in North America where almost no one is of English ancestry, yet they are English-speaking.
The same sort of social/demographic upheavals and changes that can create large language spread, are also the same kind that can create homogenization towards a single language despite people speaking many languages.
In the case of Thailand, the same political forces pressured the Chinese into intermarrying with the Thai, so genetics do come into play. But a clean victory was won over language; that didn't happen with genetics.
But, on the other hand, ‘While in most populations genetic and linguistic relations match, mismatches occur regularly as a result of language shift’: https://www.pnas.org/doi/10.1073/pnas.2122084119