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Gary A. King M. Thomas P. Gilbert Eske Willerslev Matthew J. Collins Harry Kenward 《Journal of archaeological science》2009
We report the recovery of short fragments of PCR amplifiable ancient DNA from exoskeletal fragments of the grain weevil Sitophilus granarius (L.) extracted from Roman and medieval deposits in Northern England. If DNA preservation in archaeological insect remains is widespread then many applications in the spheres of evolutionary studies and archaeology can be conceived, some of which are outlined. 相似文献
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ABSTRACT In research conducted some 20 years ago, we elucidated the starkly lower suburbanization propensities of black households in the Washington, D.C. metropolitan area. The paper showed that simulated closure of large socio‐economic gaps between blacks and whites did little to diminish prevailing high levels of residential segregation or otherwise enhance moves by black households to areas of educational, employment, and housing opportunity. Some two decades later and in the wake of significant urban evolution, this paper assesses anew racial variations in residential location choice. Results of the multinomial logit (MNL) analysis indicate large, persistent racial differentials in intrametropolitan residential location choice. While black location choice in 2000 was relatively more dispersed than in 1980, it remained remarkably concentrated in D.C. and Prince George's County. As in our prior analysis, results showed that large simulated gains in black economic and educational status had little effect on prevailing racial segregation. These findings underscore the ongoing, limited access of black households to schooling, employment, and homeownership opportunities available outside traditional areas of settlement. In marked contrast, the locational choices of Latino and immigrant households bore greater similarity to those of whites and were more sensitive to improvements in socio‐economic status. 相似文献
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This research examines the evidence for prehistoric ceramic exchange networks over the last 2000 years in northwest Alaska through the use of neutron activation analysis of ceramic artifacts. Results from ceramic analysis on eight coastal and inland archaeological sites identified three source macrogroups and three associated subgroups. Clay source diversity and shared source macrogroups between geographically distant sites suggest the use of multiple sources and/or the movement of pots between production locales, mirroring related patterns in pottery stylistic data. Although additional analytical work is needed to fully understand the changing character of clay procurement and ceramic distribution across this time period, this study provides exploratory data on past ceramic production and distribution that hints at changes in exchange and territoriality in northwest Alaska during the late Holocene. 相似文献