Population processes in the Nile Valley at the beginning of the Holocene, the El-Barga clue
Résumé
The Early Holocene site of El-Barga in Nubia was discovered in 2001 by the Swiss archaeological mission in Sudan and has been excavated over the last decade. Two settlements were identified based on archaeological and radiometric grounds: a Mesolithic assemblage (7800 - 6900 BCE) and an Early Neolithic cemetery ( 6000 – 5500 BCE). This location is of the utmost importance in the Nubian Nile Valley because it is the only one documenting, with a substantial number of well-preserved individuals, the transitional period leading to the onset of the Neolithic. Based on the morpho-metrical studies of the El-Barga collections, we will address, through both classical methods and conventional and high resolution tomographic acquisitions, the issue of continuity or replacement of the Late Pleistocene populations of the Nile Valley at the onset of the Holocene. The comparative morphometrical analyses of the dental remains show strong biological affinities between the Mesolithic sample from El-Barga and the Nubian Epipalaeolithic populations from Jebel Sahaba. These characteristics significantly differentiate the Mesolithic and Early Neolithic samples at El-Barga. These phenotypic data were supplemented by the analysis of the dental tissue proportions and the enamel-dentine junction conformation of a sample of incisors and molars from both assemblages. In addition, the most complete cranium from both samples were selected for a comparative geometric morphometric analysis. The results support the hypothesis of a biological differentiation between the two El-Barga populations. In addition, it is unlikely that these differences would be related to dietary changes on such a short timescale and at the onset of pastoralism. Therefore, without excluding the possibility of a certain level of continuity, the integrative and comparative anthropological study of the two El-Barga groups, separated in time by less than a millennium, reveals the complexity of the history of population processes in the Nile Valley during this crucial period, although poorly documented, of cultural transition at the beginning of the Holocene.