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51.
New ages for the post-Howiesons Poort,late and final Middle Stone Age at Sibudu,South Africa 总被引:1,自引:0,他引:1
Zenobia Jacobs Ann G. Wintle Geoffrey A.T. Duller Richard G. Roberts Lyn Wadley 《Journal of archaeological science》2008
Optically stimulated luminescence (OSL) measurements are reported for single grains of quartz from deposits within Sibudu rock shelter. Such measurements enable rejection of unrepresentative grains and application of the finite mixture and central age models to obtain the most reliable age estimates. Three types of single-grain equivalent dose (De) distributions were observed: one sample represented a single dose population, three samples indicated mixing between Iron Age (IA) and Middle Stone Age (MSA) deposits, and 10 samples (in addition to the three mixed samples) showed scattered distributions. The latter type resulted from differences in the beta dose received by individual grains. For these samples, the beta doses were modelled and adjusted accordingly. Ages for the 14 samples collected from MSA deposits post-dating the Howiesons Poort (HP) resulted in three age clusters, which are stratigraphically consistent with the three informally named cultural phases at Sibudu: namely, the post-HP, late MSA and final MSA. Weighted mean ages of 58.5 ± 1.4 ka, 47.7 ± 1.4 ka and 38.6 ± 1.9 ka were calculated for these phases, respectively. The three phases were separated by two occupational hiatuses with durations of 10.8 ± 1.3 ka and 9.1 ± 3.6 ka. We hypothesise that the punctuated presence of humans at Sibudu was determined by large-scale fluctuations in climate during oxygen isotope stage (OIS) 3, which resulted in alternating wet and dry periods. Phases of occupation correspond to wet periods when fresh water was available in the Tongati River, whereas intervals of site abandonment correspond to dry periods when people were forced to migrate in search of a reliable source of fresh water. Where people migrated to, remains unresolved. 相似文献
52.
Bitumen, found in abundance in Mesoamerica’s southern Gulf Coast region in natural seeps and in many archeological contexts, is an important economic resource and exchange item that has received little consideration in Mesoamerica. Analyses of archeological, ethnoarcheological, and experimental data provide insights on the organization of bitumen processing activities, and the end product (archeological bitumen), which the Olmec (1200–400 BC) used in the production of many items. Archeological data are derived from investigations at El Remolino and Paso los Ortices— two Early Formative period levee sites in the San Lorenzo Olmec region. Our findings suggest that among the Olmec, bitumen processing was organized as a specialized activity, involving multiple production stages, but not necessarily elite involvement or control. 相似文献
53.
Tanzania Maasai began large‐scale urban labour migration in the mid‐1990s, impelled by livestock losses from disease, drought and land alienation. Although they were readily hired in cities as night watchmen and security guards, many urban citizens expressed condescending views of the migrants, typifying them as ‘unmodern’, and as curious young warriors who were lazy, naive, drunk and dirty. Interviews with about 200 Maasai proved these discursive characterizations to be largely incorrect. Although the State has tried over the last century to ‘develop’ and settle semi‐nomadic pastoralists, the Maasai image is widely used as part of an instrumentalist agenda, to advertise items from telephones to tourism. Lacking political or social capital, the migrants manipulate and reinforce Maasai identity by continuing to wear traditional garments (illkarash), and by engaging in practices that emphasize their difference from the ‘WaSwahili’, bolster cohesion and solidarity among themselves, and increase their chances of urban employment. 相似文献
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