Bayesian phylogenetic analysis of Semitic languages identifies an Early Bronze Age origin of Semitic in the Near East

Bayesian phylogenetic analysis of Semitic languages identifies an Early Bronze Age origin of Semitic in the Near East

The evolution of languages provides a unique opportunity to study human population history. The origin of Semitic and the nature of dispersals by Semitic-speaking populations are of great importance to our understanding of the ancient history of the Middle East and Horn of Africa. Semitic populations are associated with the oldest written languages and urban civilizations in the region, which gave rise to some of the world’s first major religious and literary traditions. In this study, we employ Bayesian computational phylogenetic techniques recently developed in evolutionary biology to analyse Semitic lexical data by modelling language evolution and explicitly testing alternative hypotheses of Semitic history. We implement a relaxed linguistic clock to date language divergences and use epigraphic evidence for the sampling dates of extinct Semitic languages to calibrate the rate of language evolution. Our statistical tests of alternative Semitic histories support an initial divergence of Akkadian from ancestral Semitic over competing hypotheses (e.g. an African origin of Semitic). We estimate an Early Bronze Age origin for Semitic approximately 5750 years ago in the Levant, and further propose that contemporary Ethiosemitic languages of Africa reflect a single introduction of early Ethiosemitic from southern Arabia approximately 2800 years ago. pdf

While I know this is old news, I’m  having an Afro-Asiatic weekend, and I missed this last year. This isn’t a million miles away from the conclusion I got from examining the reconstructed proto words of proto Semitic a while ago; only about 750 years different (based on the presence of silver and antimony). 

I finally found my old work that records Ehret’s older date for proto Semitic as being the roughly similar to Proto Cushitic (about 10,500 bp to 10,000 bp). If this isn’t an admission that he’d seriously overestimated the dates in his earlier work on AA, I don’t know what isn’t. It supports my criticism of his dating of proto Cushitic as being about 40% out, considering how slashed the time frame for Semitic is (nearly half). This brings all his dates for AA languages into a Neolithic time frame if you apply the same rule to them as a group. I was amused to see him clinging onto an African origin for PAA like grim death, given that the DNA, archaeology and proximity of Semitic languages to PIE and Sumerian really doesn’t leave this as a viable option anymore. Essentially the ‘African origin’ needs to find a cultural or biological expansion from Africa dating to about 11k ago, and AFAIK so far the only suitable population movement across North Africa in that era goes from Asia into Africa (Capsian culture). Then it needs to find a really good reason why Nubians speak a Nilo Saharan language, when they apparently shared a common culture with Afro-Asiatic speaking upper Egyptians before the Neolithic hit Africa.

Some people (who shall remain nameless) are adamant that the E3b1 Y chr is the Y chr related to the expansion of Afro-Asiatic languages. This is incorrect in at least two cases, as Chadic is not at all associated with this, but with the R1b-V88, which arrived from Asia in the neolithic (or Holocene), and neither is Semitic which is Asian and associated with the spread of J1 (also non-African). Afro-Asiatic languages are associated with the expansion of Neolithic Y chromosomes, not E3b1. I’d also like to add that in expansions of this type, languages appear to be spread patrilinealy, not matrilinealy, the Bantu expansion and observations from other expanding farmers v hunter gatherers don’t have the maternal hunter gatherers language being preserved.

My main objections to an African origin for Proto Afro-Asiatic.

The nouns don’t reconstruct to a ceramic using African hunter gatherer landscape, but to an aceramic West Asian early Neolithic landscape. 

There are no population movements out of Africa known that are recent enough to have carried proto Semitic into Asia. The last one was about 22,000 years ago, traced by the expansion of the M78 Y chr and the Kebaran culture (the Mushabian’s origin is open for debate, but it’s also too early). This is just impossibly old. Anything more than 11,000 years and you can’t be in the same language family. So many accumulated changes will have occurred after that time that they will only bear the same level of relation to each other as two random non related language groups. 

The known population movements between Africa and Asia that could have carried the language between them in the relevant time frame all go into Africa from Asia. 

Proto Semitic shows a proximity to both Sumerian and Anatolian Neolithic proto Indo European, which places it in Asia about 9,000 years ago. Even if you think the Anatolian theory is junk, it has loan words into the later PIE about 5k ago. This leaves a narrow time frame for the movement between Asia and Africa (11k max language age - 9k for AN PIE=2,000 years), and the arrival of Neolithic farmers into Africa via the Sinai sits smack in the middle of this time frame. 

Corrected dating for Afro-Asiatic (see above comments on Ehret) shows its something like a maximum of 11,000 years old. The main supporter for the E3b1/Kebaran scenario, Ehret, is now slicing big chunks of time off his calculated dates. This places AA languages into an essentially late Holocene (if African) or early Asian neolithic scenario. Not a match for the Kebaran/E3b1 expansion.

 Nubian is not Afro-Asiatic. Nubians and upper Egyptians shared a common culture in the Holocene with each other and the western desert ceramic cultures, but they apparently didn’t speak even remotely related languages by the time of state formation in Egypt. This is suggestive of Afro-Asiatic replacing the original pre-Badarian languages, leaving Nubians isolated like an island in a sea of Afro-Asiatic. It also nails the arrival of Afro-Asiatic in upper Egypt to a time after the ceramic Nilo-Saharans got there (which was about 10,500 bp) fixing it to a younger age than this. The only influx after this into the area that we know about is the arrival of the Neolithic from Asia about 7,000 BP in upper Egypt. Nilo Saharan has a very  similar age to Afro-Asiatic (Holocene), and matches pretty well to the spread of the first ceramic using people across the Sahara and down the Nile, including upper Egypt. It’s fragmented distribution is very suggestive of a much wider territory, now occluded by later waves of Afro-Asiatic. The isolation of the Nubian NS language, when using corrected dates, comes into an era when the Neolithic pastoralists arrived from Asia into NE Africa.  

The distribution of Afro-Asiatic in Africa has a very strong relationship to the spread of Neolithic Y chromosomes (particularly Chadic and Berber). Asian ones that enter via the Sinai mainly moved into East Africa and Lake Chad. NE African Y chr M81 shows a match to the old spread of Berber languages (from the Nile Delta in the Neolithic) prior to Arabization .

 Proto Cushitic, and all the African and Asian AA languages,  reconstruct with nouns for sheep and goats, Asian animals that don’t even appear in Africa until 8,000 BP. Archaeology tracks these pastoralists moving from the Nile Delta with their herds into North West Africa, East Africa and  Lake Chad, with large chunks of their male ancestry traceable to Neolithic Asia. Using the archaeology to correct the dates for proto Cushitic means it can only be of a Neolithic age, possibly be in the 5k-6k date range. This does not support a Holocene or older date for PAA in Africa, and is more evidence connecting it to the Asian Neolithic.

 So…what are you are left with in support of an African origin? Not a lot really. That there’s more diversity and structure in Africa, but that’s about it. Omotic as a pre-agricultural AA language doesn’t really stand up to scrutiny, with several publications suggesting they originally spoke Nilo Saharan but adopted Afro-Asiatic in the Neolithic, or of it being an off shoot of Cushitic, or not even Afro-Asiatic. The main supporter for an ancient African origin for Afro-Asiatic tied to E3b is slashing huge amounts of time off his estimated dates (about 45% for proto Semitic).

The real issue for anyone claiming an African origin for PAA is to show some population/cultural movement from Africa into Asia about 11,000 to 10,000 years ago, or even any time close. This is the real ‘brick wall’ the claims for an African urheimat run into. Until someone can explain how it managed to ‘swim upstream’ against the arrival of the Capsian and Neolithic arrivals from the Levant, IMO the claims for an African origin for PAA jus don’t fit the biological or archaeological evidence.

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One response to “Bayesian phylogenetic analysis of Semitic languages identifies an Early Bronze Age origin of Semitic in the Near East

  1. Reblogged this on oogenhand and commented:
    Comparative linguistics and genetics are hobbies of me.

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