Saturday, November 26, 2016

Review: Haber, Marc et al. (2016), Chad Genetic Diversity Reveals an African History Marked by Multiple Holocene Eurasian Migrations

 Haber, Marc et al. (2016), Chad Genetic Diversity Reveals an African History Marked by Multiple Holocene Eurasian Migrations, The American Journal of Human Genetics  ,

Haber at al speculate that there were several migrations of Eurasians rom Arabia,  into Chad beginning around 7200 ya, which led to the origin of R1b-V88, a major y-Chromosome in much of Africa.. These authors wrote:
“We detected the earliest Eurasian migrations to Africa in the Laal-speaking people, an isolated language group of fewer than 800 speakers who inhabit southern Chad. We estimate that mixture occurred 4,750–7,200 ya, thus after the Neolithic transition in the Near East, a period characterized by exponential growth in human population size. Environmental changes during this period (which possibly triggered the Neolithic transition) also facilitated human migrations. The African Humid Period, for example, was a humid phase across North Africa that peaked 6,000–9,000 ya37 and biogeographically connected Africa to Eurasia, facilitating human movement across these regions.38 In Chad, we found a Y chromosome lineage (R1b-V88) that we estimate emerged during the same period 5,700–7,300 ya (Figure 3B). The closest related Y chromosome groups today are widespread in Eurasia and have been previously associated with human expansions to Europe.39, 40 We estimate that the Eurasian R1b lineages initially diverged 7,300–9,400 ya, at the time of the Neolithic expansions. However, we found that the African and Eurasian R1b lineages diverged 17,900–23,000 ya, suggesting that genetic structure was already established between the groups who expanded to Europe and Africa. R1b-V88 was previously found in Central and West Africa and was associated with a mid-Holocene migration of Afro-asiatic speakers through the central Sahara into the Lake Chad Basin.8 In the populations we examined, we found R1b in the Toubou and Sara, who speak Nilo-Saharan languages, and also in the Laal people, who speak an unclassified language. This suggests that R1b penetrated Africa independently of the Afro-asiatic language spread or passed to other groups through admixture.”

Thusly, according to Haber et al, “Chadian R1b emerged 5,700–7,300 ya, whereas most European R1b haplogroups emerged 7,300–9,400 ya. The African and Eurasian lineages coalesced 17,900–23,000 ya”. 

This statement is contradictory. How could Chadian R1b-V88 emerge 5,700 ya, and R1b-M269 emerge7,300 ya—but—“the African and Eurasian lineages coalesced 17,900–23,000 ya”.  The statement is contradictory because how could V-88 and M-269 coalesce 23,000 ya, when they did not  allegedly emerge  until 11-13,000 years after their proposed coalesce time.

In addition, to an incongruent coalesce time, there is no archaeological evidence for migration back into Africa 7,300 ya. we do see evidence of Africans migrating into the Levant. These Africans were Natufians.

By 13,000 BC, according to J.D. Clark said that the Natufians were collecting grasses which later became domesticated crops in Southwest Asia. In Palestine the Natufians established intensive grass collection. Ehret and  Wendorf,  have observed that  the Natufians used the Ibero-Maurusian tool industry and spread agriculture throughout Nubia into the Red Sea. 
The Natufians practiced evulsion of the incisors the same as Bantu people and inhabitants of the Saharan fringes. The modern civilizations of the Middle East were created by the Natufians. Since the Natufians came from Nubia, they can not be classified as Eurasians.
    Trenton W. Holliday, tested the hypothesis that if modern Africans had dispersed into the Levant from Africa, "tropically adapted hominids" would be represented  in the archaeological history of the Lavant, especially in relation to the Qafzeh-Skhul hominids. This researcher found that the Qafzeh-Skhul hominids (20,000-10,000),were assigned to the Sub-Saharan population, along with the Natufians samples (4000 BP). Holliday also found African fauna in the area.
Holliday confirmed his hypothesis that the replacement of the Neanderthal people were Sub-Saharan Africans. This shows that there were no Eurasian types in the Middle East between 20,000-4,000ya, when Haber et al speculated Y-chromosomes R-V88 and R-M269  coalesced .

Moreover, we clearly see the continuity between African culture from Nubia to the Levant. This view is supported by the Natufians who originated in Africa, and took the Ibero-Maurusian tools into Europe, North Africa and the Middle East. 
Holliday wrote: "The current study demonstrates African-like affinities in the body shape of the Qafzeh-Skhul hominids. This finding is consistent with craniofacial evidence (Brace 1996) and with zooarchaeological data indicating the presence of African fauna at Qafzeh (Rabinovich and Tchernov 1995; Tchernov 1988, 1992)" (p.64). The continuity in the spread of Sub-Saharan fauna, flora and physical type in the Levant between 4000-23,000 ya, means that  R1 more than likely originated in Africa,  instead of Eurasia. Haber et al (2016) is invalid and lacks archaeogenetic evidence to support their conclusions.


J.D. Clark , "The origins of domestication in Ethiopia", Fifth Panafrican Congress of prehistory and quaternary Studies, Nairobi,1977

Christopher Ehret ( "On the antiquity of agriculture in Ethiopia", Jour. Of African History 20, [1979], p.161)

Trenton W. Holliday. (2000) "Evolution at the Crossroads: Modern Human Emergence in Western Asia, American Anthropologist,102(1).

F. Wendorf, The History of Nubia, Dallas,1968, pp.941-46). 

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