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31.
Laura B. Niven Charles P. Egeland Lawrence C. Todd 《Journal of archaeological science》2004,31(12):1783-1794
Bison bison mandibular molars from the Late Plains Archaic kill/butchery sites of Buffalo Creek (Wyoming) and Kaplan-Hoover (Colorado) exhibit significant frequencies of dental enamel hypoplasia (DEH), a defect believed to reflect information about physiological status of individual animals. This study provides a methodology to estimate the ontogenetic and seasonal timing of DEH formation in bison dentition. Integration of these estimates with data from bison life history and grassland ecology allows inferences on age- and season-specific factors exacerbating periodic physiological declines that were recorded in the form of enamel hypoplasias. Differences between assemblages indicate regional variability in grassland conditions, with data from Buffalo Creek pointing to recurrent drought that reduced forage capacity and contributed to physiological stress in bison over two consecutive years. Seasons of physiological stress reflected in the DEH correspond to each of the three kill events at the locality, suggesting that predictability of bison behavior in this location was a critical factor in influencing the seasonal timing and location of repeated hunting episodes. Unlike Buffalo Creek, timings of stress episodes are not consistent with season of death in the Kaplan-Hoover bison assemblage, suggesting that favorable grassland conditions were the primary factor influencing timing of this large single-kill event in order to provision for the upcoming winter. DEH analysis represents a developing approach in the construction of models addressing key aspects of local grassland and bison ecology as well as offers unique insights into the hunting strategies and subsistence decisions of Late Plains Archaic foragers. 相似文献
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David R. Braun Thomas Plummer Peter Ditchfield Joseph V. Ferraro David Maina Laura C. Bishop Richard Potts 《Journal of archaeological science》2008
The archaeological record of Oldowan hominins represents a diverse behavioral system. It has been suggested that exploitation of lithic resources by Oldowan hominins was simplistic and represented mostly use of local sources of stone. Here we investigate the raw material selection and transport behaviors of Oldowan hominins reflected in the stone artifact assemblages from the Kanjera South Formation, South Rachuonyo District, Kenya. Using geochemical methods (ED-XRF) artifacts are linked to primary and secondary source outcrops throughout southwestern Kenya. These data show that hominins selected raw materials for transport at frequencies that are significantly different from their availability on ancient landscapes. Furthermore, a substantial proportion of the assemblage represents transport over relatively long distances (>10 km). Our study further suggests that in the early stages of stone tool use hominins used a wide variety of raw materials and selected these materials at some distance from their eventual discard locations. Early hominin behavior may have incorporated an understanding of raw material source distributions across a more extensive landscape than has been previously documented. This supports the growing perspective that Oldowan technology represents a more complex behavioral pattern than is usually associated with the beginnings of hominin tool use. 相似文献
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Paola Boscato Christian Carioni Andrea Brandolini Laura Sadori Mauro Rottoli 《Journal of archaeological science》2008
The persistent uncertainty on the classification of the “new” glume wheat found in Neolithic and Bronze Age sites from Greece and other European settlements might be resolved only through analysis of its ancient DNA. Tools able to discriminate among different Triticum species on the basis of scarce, very damaged DNA, are therefore essential. While current attempts concentrate on DNA fragments sequencing and comparison, in some instances PCR-based selective amplification techniques might offer a cheaper and quicker alternative. The purpose of this research was therefore the identification of species-specific primers, able to distinguish caryopses of Triticum timopheevii subsp. timopheevii from those of Triticum turgidum subsp. dicoccum. Primers and their working conditions were defined and optimized using DNA from modern accessions. The ribosomal primers ITS1 tim and ITS2 tim, and the nuclear primer acetyl-coenzyme A tim clearly discriminated the sequences of Triticum timopheevii from other species. Finally, Neolithic charred wheat grains found in the sites of Sammardenchia (Pozzuolo del Friuli, Udine) and La Marmotta (Lago di Bracciano, Roma), belonging to the “new” wheat type or to emmer, were tested with the three selected primers. However, the results were not conclusive, because the samples analysed were apparently too degraded to yield useful DNA. 相似文献
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Laura Pulido 《对极》2002,34(4):762-788
This paper explores the third-world left in Los Angeles, from 1968–1978. In it I examine the political ideology and foci of one organization for each of the major racial/ethnic groups of the time: African Americans (Black Panther Party), Chicanas/os (El Centro de Accion Social y Autonomo [CASA]), and Japanese Americans (East Wind). In addition to reclaiming this relatively unknown history, I seek to explain the differences in the various organizations by analyzing them within the context of differential racialization. I argue that the distinct nature of each organization is at least partly due to the particular racial position of each racial/ethnic group within the local racial order. 相似文献
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Laura Marchionni 《Archaeological and Anthropological Sciences》2016,8(2):241-255
The basin of the Zanjón Rojo and Blanco is located in the northeast of the Central Plateau of Santa Cruz province (Argentina). Each sector of the basin has specific characteristics which represent different microenvironments. We have studied two different archeological contexts in the period from the Final Pleistocene to Late Holocene in each of these sectors. In this paper, we analyze the effects of different taphonomic processes and agents on the zooarcheological assemblages in order to evaluate the role played by those that can redeposit or move bones pre- and post-depositionally during site formation in this sector of Patagonia. The bone specimens that were analyzed come from two stratigraphic contexts with wide sequences of human occupation; one is AEP-1 at Piedra Museo and the other is Cueva Maripe at La Primavera, located in the lower and upper sectors of the basin, respectively. The comparison between both sites was based on different modification patterns identified on bone surfaces for the different phases of settlement in Patagonia. The results showed complex and different taphonomic histories in both sites, and while the main processes involved in bone movement were roots and rodents, both had little significance in comparison with others, such as manganese and carbonate. 相似文献
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