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The period comprising the end of the Early Neolithic and the Middle Neolithic, dated broadly within the fifth millennium cal BC, corresponds to an interval that remains largely unknown in the extreme north-western tip of Africa. This situation contrasts with that of the Early Neolithic, a period characterised by the earliest evidence of the diffusion of a productive economy, cultivated plants and domestic animals. The paucity of data for these later phases can be explained in part by the lack of secure contexts and sequences based on radiocarbon datings of short-lived samples. The current study presents the results of the excavations of El-Khil Caves B and C that yield materials allowing re-evaluation of the chronology of a type of ceramic known as Ashakar ware. The study also identifies two traditions in the northern Moroccan Middle Neolithic. The first is heir to the so-called Impressa Mediterranean ware and rooted in the Cardial Neolithic, while the second is characterised by roulette cord impressions, red slip and tunnel lugs and probably rooted in the region of the Sahara, and has no technological precedents in the study area.  相似文献   
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The study presents the results of neutron activation analysis (NAA) of contemporary pottery from Tigray Regional State, northern highland Ethiopia. This is the first regional-scale study of ceramic composition of Tigray’s pottery and is part of an ethnoarchaeological study of the material and social contexts of pottery production and consumption in Tigray’s Eastern (Misraqawi), Central (Mehakelegnaw), and North-western (Semien Mi’irabawi) zones. The analysis identifies clear compositional groups with strong regional patterns, an encouraging result for the use of NAA to study Tigray’s ancient pottery trade. Significantly, the study further contributes to discussions of how mutually constituted social identities of potters and consumers affect compositional patterning in the distribution of pottery in market networks.  相似文献   
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Four decades have passed since Harlan and Stemler (1976) proposed the eastern Sahelian zone as the most likely center of Sorghum bicolor domestication. Recently, new data on seed impressions on Butana Group pottery, from the fourth millennium BC in the southern Atbai region of the far eastern Sahelian Belt in Africa, show evidence for cultivation activities of sorghum displaying some domestication traits. Pennisetum glaucum may have been undergoing domestication shortly thereafter in the western Sahel, as finds of fully domesticated pearl millet are present in southeastern Mali by the second half of the third millennium BC, and present in eastern Sudan by the early second millennium BC. The dispersal of the latter to India took less than 1000 years according to present data. Here, we review the middle Holocene Sudanese archaeological data for the first time, to situate the origins and spread of these two native summer rainfall cereals in what is proposed to be their eastern Sahelian Sudan gateway to the Red Sea and the Indian Ocean trade.  相似文献   
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First visited by westerners in the mid-nineteenth century, Saharan rock art has since received a great deal of attention. The richness and diversity of this region is recognised by the inclusion on the UNESCO World Heritage list of three properties: Tassili-n-Ajjer in Algeria, Tadrart Acacus in Libya, and Ennedi in Chad. The situation in many North African countries now makes this vast region very difficult to access: safety in the field is not guaranteed and few research funds are available. Today, a new generation of African and foreign scientists has no access to rock art sites in the north of the continent and the lack of fieldwork may entail a lack of safeguard and awareness. The growth of digital technologies over the last 15 years has revolutionised methods for recording rock art sites. Digital technologies are also used to mitigate the gap between artworks and accessibility in those countries where turmoil and social instability make fieldwork impossible. However, much of the documentation and most digital recordings of artworks currently available on the Internet lack an archaeological context. Equally, many of these websites barely mention methodological and theoretical aspects. It is also difficult to understand the extent of awareness among local communities in remote areas—sometimes suffering a digital and linguistic divide—and if (and how) they are genuinely able to exploit these digital resources. Here, I collate some examples from different parts of the Sahara illustrating that the recording, management and dissemination of rock art still present highs and lows. I argue that we should share theories and methods within the digital scientific community, with a view to adopting a shared nomenclature and a public thesaurus, making our cataloguing criteria explicit and, finally, developing an ethical code of conduct involving local communities.  相似文献   
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Advanced data capture techniques, cost-effective data processing, and visualization technologies provide viable solutions for the documentation of archaeological heritage and material culture. Work at the UNESCO World Heritage site of Çatalhöyük has demonstrated that new digital approaches for capturing, processing, analyzing, and curating stratigraphic data in 3D are now feasible. Real-time visualization engines allow us to simulate the stratigraphy of a site, the three-dimensional surfaces of ancient buildings, as well as the ever-changing morphology of cultural landscapes. Nonetheless, more work needs to be done to address methodological questions such as follows: can three-dimensional models and stratigraphic relationships, based on 3D surfaces and volumes, be used to perform archaeological interpretation? How can a 3D virtual scenario become the interface to cultural data and metadata stored in external online databases? How can we foster a sense of presence and user embodiment in the simulation of ancient cities and archaeological sites? This article aims to provide viable solutions to the methodological challenge of designing a comprehensive digital archaeological workflow from the data acquisition and interpretation in the field to a three-dimensional digital data curation based on interactive visualization, searchable 3D data, and virtual environments. This work describes the results we achieved developing the application Dig@IT, a multi-platform, scalable virtual reality tool able to foster archaeological data analysis, interpretation, and curation in a realistic and highly interactive virtual environment.  相似文献   
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