The same authors dated Proto-Indo-European at 8.4ky, in agreement with the work of Gray and Atkinson. In the current paper they re-analyze the data of Kitchen et al. (2009) for Semitic languages, and their estimate is somewhat younger than 5,750 years of that paper. All in all, it's good to see different researchers using different techniques but coming up with similar solutions.
It is increasingly clear that while the Proto-Indo-Europeans originated in the Neolithic Near East, the Proto-Semites followed them by about three thousand years. In the latter case there is also a Y-chromosome marker (J-P58) with an apparent age in impeccable agreement with the linguistic evidence, now that the genealogical-"evolutionary" mutation wars seem to have been won.
This also brings into focus the weakness of the argument that Anthony (2007) (p. 76) brings to the table by hypothesizing that the first farmers of northern Syria were Afro-Asiatic speakers like the Semites of the Near Eastern lowlands. Semites come into the picture 5,000 years after the onset of the Neolithic, and 3,000 years after the Proto-Indo-Europeans. Their relationship with Afroasiatic speakers of Africa make it quite likely that they lived in the south, probably in Arabia, and certainly not in eastern Anatolia or northern Syria.
Indeed, the recent discovery that haplogroup J1*(xP58) is associated with Northeast Caucasian languages, together with the absence or paucity of J1 in most African Afroasiatic speakers suggests to me that the J-P58 Proto-Semites may be the result of the transfer of an African language on a basically West Asian population. Such a scenario might also explain some of the -incorrectly quantified, but nonetheless existent- African genetic components in both Jews and Arabs, as well as the pastoralist/dry-climate J1 associations.
Proceedings of the 26th International Workshop on Statistical Modelling.
Phylogenetic models for Semitic vocabulary.
Geoff K Nicholls and Robin J. Ryder
Abstract: Kitchen et al. (2009) analyze a data set of lexical trait data for twenty five Semitic languages, including ancient languages Hebrew, Aramaic and Akkadian, modern South Arabian and Arabic languages and fifteen ethiosemitic languages. They estimate a phylogenetic tree for the diversification of lexical traits using tree and trait models and methods set up for genetic sequence data. We reanalyze the data in a homplasy-free model for lexical trait data. We use a prior on phylogenies which is non-informative with respect to some of the key scientific hypotheses (concerning topology and root time). Our results are in broad agreement with those of Kitchen et al. (2009), though our 95% HPD for the root of the Semitic tree (the branching of Akkadian) is [4400, 5100]BP and we place Moroccan and Ogaden Arabic in the Modern South Arabian Group.
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