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21.
In traditional Bantu-speaking societies in southern Africa, drought is caused by breaches in rules of pollution. At times of severe drought (3–5 consecutive seasons), rainmakers ascend special hills to perform special rituals. The archaeological signature of this unique activity forms a cultural proxy for drought. New research shows that burnt daga structures also correlate with high δ15N values for small stock. Burnt structures thus form a new component to the proxy. According to the ethnography, farmers implicated in the cause burnt their grain bins, and sometimes houses, as a ritual of cleansing. The dating of these structures provides a revised climatic sequence for the plateau portion of the summer rainfall region. Among other new results, there was a drought at the end of the Mapungubwe period (ca. AD 1300). At about AD 1650, droughts associated with the arrival of maize caused people to stop growing it as food for a while.  相似文献   
22.
Small mammals are considered to be good indicators of ancient environments. One particular layer in a fortification tower of a Mediterranean Iberian village, Alorda Park (4th century BC), provided a large amount of well-preserved small mammal bones (about 19,200 remains) probably accumulated by barn owls (Tyto alba). Such an accumulation is rarely available from the Iron Age. It provides not only palaeoenvironmental data, but also further information about other studies such as morphometrics, ancient DNA and zoogeography. This article focuses on the ecological data, and attempts to develop an accurate taphonomic study to assess the reliability and statistical significance of this archaeological sample.  相似文献   
23.
The origins of raw glass used to fashion Mycenaean beads were explored using trace elements analyzed by laser ablation ICP-TOFMS. The use of this minimally destructive technique for the in-situ analysis of these beads was ideal given that the material is exceedingly rare and thus too sensitive to make use of traditional micro-sampling (e.g., by scalpel). A wide range of trace elements were measured to compare these Greek glasses to other Late Bronze Age glass coming from Egypt and Mesopotamia. Of the eleven beads analyzed, four blue glasses colored with cobalt and two blue/green glasses colored with copper have trace element compositions consistent with an Egyptian origin of manufacture. The other five of the glasses, all colored with copper, were found to conform to the composition of Mesopotamian glass. These data are the first to demonstrate direct and clear evidence for the trade of raw glass to the Mycenaean states.  相似文献   
24.
Populonia is commonly regarded as one of the most important iron working centres in Europe in the 1st millennium BC. However, multiple layers of copper slags have been recently discovered at the bottom of the slag deposit occurring along the shoreline of the underlying Baratti Gulf. Copper slag layers have been radiocarbon dated to the 9th–8th centuries BC, i.e. to an early metallurgical stage predating the later large-scale iron production. The overall features of copper slags indicate a single-step smelting process of copper-rich ores containing variable amounts of Zn and Pb. Chemical and textural features of copper slags indicate an optimised, high-efficiency metallurgical process.  相似文献   
25.
关于石片台面研究的一些问题-兼与卫奇先生商榷   总被引:2,自引:2,他引:2  
本讨论了石片台面的分类、石片台面的类型等问题。台面可能按其保留情况、性质、加工情况和形态等不同层次进行分类,本主张应着重前3个层次进行分类。在某些特殊技术形成的石片中,台面的形态因为与该打片技术密切相关故也具有一定的分类意义。  相似文献   
26.
Micromorphological analysis of sediments from the Middle Stone Age site of Sibudu Cave, KwaZulu-Natal, South Africa, provides a high-resolution sequence and evidence of site formation processes of predominantly anthropogenic deposits. This methodology allows for a detailed interpretation of individual anthropogenic activities, including the construction of hearths and bedding and the maintenance of occupational surfaces through the sweep out of hearths and the repeated burning of bedding. This analysis also provides a context for evaluating other studies at the site relating to magnetic susceptibility, paleobotany, paleozoology, anthracology, and studies of ochre.  相似文献   
27.
The fossil record suggests that modern human morphology evolved in Africa between 150,000 and 50,000 years ago, when the sole inhabitants of Eurasia were the Neanderthals and other equally nonmodern people. However, the earliest modern or near-modern Africans were behaviorally (archaeologically) indistinguishable from their nonmodern, Eurasian contemporaries, and it was only around 50,000-40,000 years ago that a major behavioral difference developed. Archaeological indications of this difference include the oldest indisputable ornaments (or art broadly understood); the oldest evidence for routine use of bone, ivory, and shell to produce formal (standardized) artifacts; greatly accelerated variation in stone artifact assemblages through time and space; and hunting-gathering innovations that promoted significantly larger populations. As a complex, the novel traits imply fully modern cognitive and communicative abilities, or more succinctly, the fully modern capacity for Culture. The competitive advantage of this capacity is obvious, and preliminary dates suggest that it appeared in Africa about 50,000 years ago and then successively in western Asia, eastern Europe, and western Europe, in keeping with an African origin. Arguably, the development of modern behavior depended on a neural change broadly like those that accompanied yet earlier archaeologically detectable behavioral advances. This explanation is problematic, however, because the putative change was in brain organization, not size, and fossil skulls provide little or no secure evidence for brain structure. Other potential objections to a neural advance in Africa 50,000-40,000 years ago or to the wider Out-of-Africa hypothesis, include archaeological evidence (1) that some Neanderthals were actually capable of fully modern behavior and (2) that some Africans were behaviorally modern more than 90,000 years ago.  相似文献   
28.
In a series of recent studies, changes in material culture and settlement pattern in the Late Glacial of Northern Europe have been linked to the eruption of the Laacher See volcano. This eruption occurred c. 13,000 years ago towards the end of the Allerød chronozone. It is argued that the tephra fall-out from this eruption set in motion significant demographic fluctuations along the northern periphery of Late Glacial human settlement and that these led to a number of material culture transformations. In particular, the emergence of the regionally distinct techno-complexes with large tanged points – the Bromme culture in southern Scandinavia and the Perstunian culture in northeastern Europe – and the temporary abandonment of central European regions are thought to relate to this eruption. While numerous archaeological datasets are in accord with this ‘Laacher See hypothesis’, the forcing mechanism or mechanisms that brought about these archaeologically visible changes have remained largely unexplored. A particular challenge is to explain how some of the culture-historical effects of the Laacher See eruption seem to change or become more pronounced with distance from the eruptive centre. We here investigate one potential middle-range link between the Laacher See eruption and Late Glacial fauna and foragers: tephra as dental abrasive. We use instrumented nanoindentation to quantitatively investigate tephra from a number of sites covering the medial and distal fall-out zones as well as the dental enamel of Homo sapiens and key prey species of Late Glacial foragers. Our results show that the Laacher See tephra contained particles roughly twice as hard as even the hardest portions of any of the teeth investigated. We also suggest that fluoride-induced weakening of dental enamel may have further aggravated tooth wear. These mechanisms may have acted in concert to produce elevated levels of, in particular, animal mortality, which in turn may have led to an abandonment of the affected landscapes.  相似文献   
29.
The comparative study of sedimentary fabrics in relation to archaeological fabrics in various levels of the sites of Cova Gran de Santa Linya (Middle and Early Upper Palaeolithic) and the Roca dels Bous (Middle Palaeolithic) has made it possible to analyse the formation dynamics of the deposits and determine the extent of disturbance of the archaeological levels by natural processes. To achieve this, diagrams and two- and three-dimensional indices were calculated from the azimuth and dip angle of natural clasts and artefacts. The results indicate that the sedimentary levels were formed mainly by planar fabric shape gravitational processes (low depositional angles), which differ notably from the archaeological fabrics they contain, characterised by a greater degree of isotropy. This difference in the fabrics would reflect human activity and indicates that the archaeological levels both in Cova Gran and Roca dels Bous have not been subject to significant natural modifications, and are preserved in situ.  相似文献   
30.
Radiocarbon dates on marine shells have not been used as extensively as charcoal or bone dates for the setting up of absolute chronologies because interpreting these dates is complicated by the marine radiocarbon reservoir effect. Nevertheless marine shellfish were used widely at least during the Holocene and their shells are abundant and usually well preserved in archaeological deposits located near shorelines. Consequently prior research concerning the oceanographic conditions and the marine radiocarbon reservoir effect of a particular coastal area is needed in order to set up reliable chronologies for that region. Values of regional marine radiocarbon reservoir effect – ΔR – of coastal waters off Atlantic Iberia, some of its variability along the Holocene and its correlation with the upwelling phenomenon were determined during previous research. More data related to the ΔR values for western Portuguese coastal waters during the Late Neolithic and the Chalcolithic, a time interval badly sampled in previous research, were recently obtained. These values can be compared with ΔR values already determined for the Gulf of Cadiz. Besides the importance of these values for a better knowledge of the palaeoceanography and palaeoclimatology of Atlantic Iberia, from now on archaeologists can set up reliable chronologies for Late Neolithic and Chalcolithic contexts using marine shell samples of that origin for radiocarbon dating.  相似文献   
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