http://science.sciencemag.org/conten...cience.aar8380
The previous paper about this just used fsts, which led to endless debates about interpretation. This time we have more unequivocal statements.
North Africa is a key region for understanding human history, but the genetic history of its people is largely unknown. We present genomic data from seven 15,000-year-old modern humans from Morocco, attributed to the Iberomaurusian culture. We find a genetic affinity with early Holocene Near Easterners, best represented by Levantine Natufians, suggesting a pre-agricultural connection between Africa and the Near East. We do not find evidence for gene flow from Paleolithic Europeans into Late Pleistocene North Africans. The Taforalt individuals derive one third of their ancestry from sub-Saharan Africans, best approximated by a mixture of genetic components preserved in present-day West and East Africans. Thus, we provide direct evidence for genetic interactions between modern humans across Africa and Eurasia in the Pleistocene.Also, we have work to do boys:Consistently, we find that all males with sufficient nuclear DNA preservation carry Y haplogroup E1b1b1a1 (M-78; table S16). This haplogroup occurs most frequently in present-day North and East African populations (18). The closely related E1b1b1b (M-123) haplogroup has been reported for Epipaleo- lithic Natufians and Pre-Pottery Neolithic Levantines (“Le- vant_N”) (16). Unsupervised genetic clustering also suggests a connection of Taforalt to the Near East. The three major components that comprise the Taforalt genomes are maxim- ized in early Holocene Levantines, East African hunter-gath- erer Hadza from north-central Tanzania, and West Africans (K = 10; Fig. 2. In contrast, present-day North Africans have smaller sub-Saharan African components with minimal Hadza-related contribution (Fig. 2
Once the samples are out, qpGraph time.We further characterized the sub-Saharan African-related ancestry in the Taforalt individuals using f4 statistics in the form f4(Chimpanzee, African; Yoruba/Mende, Natufian). We find that Yoruba/Mende and Natufians are symmetrically related to two deeply divergent outgroups, a 2000 yBP ancient South African (“aSouthAfrica”) and Mbuti Pygmy, respectively (|Z| ≤ 1.564 SE; table S11). Since f4 statistics are linear under admixture, we expect Taforalt not to be any closer to these outgroups than Yoruba or Natufians if the two-way admixture model is correct. However, we find instead that Taforalt is significantly closer to both outgroups (“aSouthAfrica” and “Mbuti”) than any combination of Yoruba and Natufians (Z ≥ 2.728 SE; Fig. 4). A similar pattern is observed for the East African outgroups Dinka, Mota and Hadza (table S11 and fig. S20). These results can only be explained by Taforalt harboring an ancestry that contains additional affinity with South, East and Central African outgroups. None of the present-day or ancient Holocene African groups serve as a good proxy for this unknown ancestry, because adding them as the third source is still insufficient to match the model to the Taforalt gene pool (table S12 and fig. S21). However, we can exclude any branch in human genetic diversity more basal than the deepest known one represented by aSouthAfrica (4) as the source of this signal: it would result in a negative affinity to aSouthAfrica, not a positive one as we find (Fig. 4). Both an unknown archaic hominin and the recently proposed deep West African lineage (4) belong to this category and therefore cannot explain the Taforalt gene pool.
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Originally Posted by rafc
