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71.
This study examines preservation of microfossils identified as introduced Ipomoea batatas in soils from northern New Zealand. Starch grains and xylem cells showed highly variable preservation, from good to extremely poor. For starch grains, the latter included brown-staining, expansion and distortion of the grain and vacuole, loss of the Maltese cross, pitting, cracking, fragmentation and disintegration. Degraded xylem showed similar brown-staining, occasional cracking, cross-wise fragmentation, with wall pits becoming progressively less visible or showing distortion, expansion and coalescence.  相似文献   
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Archaeologists from New Mexico State University surveyed El Camino Real, the earliest long-distance trail established by European colonists in North America, from Las Cruces, New Mexico, to El Paso, Texas. Our goal was to determine the location and condition of this historic trail within a strip of land that has witnessed significant agricultural, suburban, and urban development in recent years. Due to this development, many scholars have assumed that all physical traces of the Camino Real have been destroyed. Results of our research, however, suggest that not all remnants of the trail and related campsites have been lost.  相似文献   
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Harvesting different species as foods or raw materials calls for differing skills depending on the species being harvested and the circumstances under which they are being taken. In some situations and for some species, the tactics used are mainly behavioral—that is, people adjust, or adapt, their own actions to fit the behavior and circumstances of the species they are taking. Under other circumstances and for other species, the skills and tactics used may call for greater environmental preparation or manipulation. Therefore, instead of trying to distinguish people today and in the past as either foragers or farmers, it makes sense to define human subsistence behavior as an interactive matrix of species and harvesting tactics, that is, as a provisions spreadsheet.  相似文献   
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Local earthenware associated with enslaved African populations in the Americas, variously called Colono-Ware, Afro-Caribbean Ware. Yabbas, and Criollo ware, has received considerable attention from researchers. What unifies this disparate group of ceramics is not method of manufacture, design and decoration, or even form and function but the association or potential association with African diaspora populations. The ceramics incorporate some skills and techniques possibly brought by African potters to the Americas, as well as skills reflecting European and Native American traditions, and local adaptations in form, function, and manufacture. Analogies linking African ceramic traditions to American industries have at times been employed uncritically and have relied on generalized characteristics to infer overly specific meanings. With particular reference to low-fired earthenwares from Jamaica, this paper examines the historical and cultural context of these ceramics and the methodological and theoretical problems faced in their interpretation.  相似文献   
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