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Phosphate analysis and trace metals analysis were used to determine activities that took place on plaster floors in domestic contexts at the ancient Maya site of Chunchucmil, Yucatan. Research on activities and the use of space contributes to an understanding of social relations within household groups as well as unforeseen patterns that structure refuse discard. The floors analyzed in this paper pertain to three structures in two neighboring houselots dating to the Early Classic (300–600 A.D.) period. Data from the chemical analyses were utilized in conjunction with associated architectural features and artifacts found on the floors. These three lines of information were interpreted with the help of models developed from ethnographic and ethnoarchaeological research. The results demonstrated functional differentiation of rooms within elaborate residences and suggested that front rooms were used to host visitors. The results also suggested that different types of debris were managed differently. Finally, chemical analyses suggest that non-elite Maya occasionally enacted rituals often restricted to elites.  相似文献   
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Survey of the coastal and inter-tidal zone at Kilwa in Tanzania resulted in the discovery of a series of artificial causeways and platforms at the entrance to the harbour of Kilwa Kisiwani, an important port trading with East Africa and southern Asia from around the 13th century. These appear to be part of a phase of monumental stone building at Kilwa in the 13th to 16th centuries, and represent a prosperous, confident Kilwa, impressing foreigners arriving by sea. Although necessarily speculative, several possible interpretations of their functions are advanced including navigation, protective breakwaters, access to marine resources, or ceremonial use.
© 2007 The Author  相似文献   
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Palynology, radiocarbon dating, and open-section stratigraphies from archaeological trenches are used to examine the impact of human activity around the time of Norse landnám on vegetation and landscape associated with a small farm (Ø34) in the Qorlortoq valley, Eastern Settlement, Greenland (61° N 45° W). Peat deposits from a mire abutting the Norse ruins revealed a discontinuous palaeoenvironmental record containing a possible hiatus from ca. AD 410–1020. Palaeovegetational data were recovered either side of this period. Pollen assemblages suggest that open Salix scrub dominated the landscape during the pre-settlement phase. The later phases of landnám resulted in the creation of hay fields and heavily-grazed grassy heath. Site abandonment is reflected by a re-expansion of Salix. This occurs shortly before the onset of deposition of a Sphagnum peat, dated to cal AD 1420–1630 (2σ) and reflecting an increase in mire surface wetness, probably in response to a deteriorating climate. Radiocarbon dates were obtained on peat and plant macrofossils sampled from either side of the proposed hiatus at two different but closely-spaced (<20 m) locations across the mire. These produced significantly different dates for the cessation of peat formation in the pre-landnám period (cal BC 2130–1770 and cal AD 240–410 respectively), but near-synchronous dates for the recommencement of peat growth (cal AD 890–1150 for peat and a probably more reliable interval of cal AD 1020–1190 based on plant macrofossils). It is suggested that this hiatus may represent the first direct evidence for peat cutting in Norse Greenland.  相似文献   
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Franklin J. James spent much of his career working to understand and improve our metropolitan communities. His interests were varied, ranging from impacts of fiscal and economic distress on urban areas to understanding socioeconomic forces reviving our central cities. During the last several years, Professor James had turned his attention to examining the positive economic impacts immigrants and ethnic communities have for reinvigorating our central cities-and beginning to investigate how non-native American's will impact America's suburbs in metropolitan settings
This preliminary exploration examines destination choices of immigrants, the characteristics of immigrant labor markets, and the determinants of immigrant earnings. The article begins to explore indirect evidence on the economic efficiency with which immigrants and native workers distribute themselves within and among labor markets as well as the assimilation process facing new immigrants. Evidence is presented to explain how the earnings of recent immigrants are affected by their human capital characteristics, their race, and ethnicity, and other factors. We reject the hypothesis that immigrants participate in a tertiary sector of urban labor markets and conclude that the determinants of immigrant earnings are similar enough to those of U.S. natives that it makes sense to assume that they work in the same primary labor market in which most native White Americans work. We find that urban labor markets for immigrants are surprisingly efficient, thus enabling immigrants to take advantage of economic opportunities. A major exception concerns what appears to be a powerful effect of discrimination on the economic progress of Black immigrants.  相似文献   
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The ancient Egyptians mummified an abundance of cats during the Late Period (664 - 332 BC). The overlapping morphology and sizes of developing wildcats and domestic cats confounds the identity of mummified cat species. Genetic analyses should support mummy identification and was conducted on two long bones and a mandible of three cats that were mummified by the ancient Egyptians. The mummy DNA was extracted in a dedicated ancient DNA laboratory at the University of California - Davis, then directly sequencing between 246 and 402 bp of the mtDNA control region from each bone. When compared to a dataset of wildcats (Felis silvestris silvestris, F. s. tristrami, and F. chaus) as well as a previously published worldwide dataset of modern domestic cat samples, including Egypt, the DNA evidence suggests the three mummies represent common contemporary domestic cat mitotypes prevalent in modern Egypt and the Middle East. Divergence estimates date the origin of the mummies' mitotypes to between two and 7.5 thousand years prior to their mummification, likely prior to or during Egyptian Predyanstic and Early Dynastic Periods. These data are the first genetic evidence supporting that the ancient Egyptians used domesticated cats, F. s. catus, for votive mummies, and likely implies cats were domesticated prior to extensive mummification of cats.  相似文献   
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