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961.
In this paper I evaluate the effects of wave and tidal erosion on element‐specific measures of phenotypic variability. Previous research has found a high correlation between skeletal weight, shape, and density and the transport potential of an element exposed to hydrodynamic forces. However, no previous studies have attempted to address the issue of within‐element sorting based on selective removal of only the smallest members of a given element class. I evaluate this hypothesis using a human skeletal sample from Bird Island (8DI52) located in Dixie County, Florida. This sample comprises two components, an eroded sample that was exposed during severe storm and tidal activity, and an uneroded sample excavated from primary context. The measurement‐specific means for the subcomponents were compared using Student's t and Wilcoxon tests and variability differences were evaluated based on standard deviations, coefficients of variation, and maximum/minimum indices. The data included maxillary and mandibular tooth dimensions and postcranial metrics. No evidence for selective winnowing based on within‐element size was found in this data set. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
962.
Unusually large fontanelles were found in four skeletons of children from a cemetery in the North West Province of South Africa. These remains date from the last decade of the 19th and first half of the 20th century. Three small infants (two of about nine months, and one of about six months) and one child (of about three years) were affected. In the case of the three‐year‐old child pathologic changes were evident on the rest of the skeleton, which probably resulted in the delayed closure. The cause of the unusually large fontanelles in the other three individuals is less clear. Some possibilities are discussed, but it seems as though general hardship and malnutrition, congenital syphilis or other infectious diseases like rubella syndrome may be involved. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
963.
Knowledge of Sicilian biology during the past is very important in understanding the complex processes that characterized the population of the Mediterranean Basin. The problem of the first Greek settlement in Sicily is essential in understanding and reconstructing the indigenous biological tissue of an island that was and still is a fundamental crossroads for migratory strategies. In this research we studied ten Sicilian series chronologically attributed to the second and first millennium BC , using discrete cranial traits. The results show that the first biologically significant Greek presence in eastern Sicily could go back to the Bronze Age, while the cosmopolitan Hellenistic city of Syracuse showed the nature of the biological pattern during the first millennium BC . Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
964.
H. TSIKOS  J. M. MOORE 《Geofluids》2005,5(4):264-271
Petrological and geochemical evidence is presented on the occurrence of aegirine in the Palaeoproterozoic Hotazel iron‐formation, which hosts the giant manganese deposits of the Kalahari manganese field, South Africa. The mineral has an essentially pure Na end‐member composition and occurs sporadically in iron‐formation immediately bordering the manganese ore beds. The development of aegirine appears to have taken place due to the action of late‐infiltrating, saline hydrothermal fluids at the expense of a pre‐existing, binary quartz–hematite assemblage. It is proposed that such a process would have overprinted (and therefore post‐dated) a spatially more extensive, low‐temperature alteration event which brought about thorough carbonate leaching, oxidation and residual enrichment of metals in the Hotazel iron–manganese rocks.  相似文献   
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Many chronological and cultural facets of Early and Middle Holocene Prehistoric Oman are still unclear. Archaeological excavations of settlements and cemeteries are adding new data to the reconstruction of a chronological and cultural framework. Wadi Shab-GAS1 is a Middle Holocene site found at the beginning of the 1980s and later destroyed by urbanisation. It is located in a rich environmental niche, on a cliff facing the sea and near a permanent freshwater source. Three years of fieldwork at this site brought to light structural remains, a cemetery and interesting material culture.  相似文献   
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