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1.
Significant advances in our understanding of ancient agricultural practices in the Americas have been made in recent years. This review of the literature focuses on studies published between 1987 and early 1994. Issues pertaining to the transition from foraging to farming include the habitability of the American tropics prior to the development of agriculture, theories on plant domestication and the origins of agriculture, regional syntheses of agricultural development, and the origin, evolution, and dissemination of domesticates in the Americas. Other topics reviewed include new techniques that have recently been applied to the study of prehistoric agriculture in the Americas, various approaches to the study of agricultural change, and ways in which research on ancient agricultural practices is being applied in modern experimental agriculture and rural development projects.  相似文献   
2.
The reemergence of cognitive studies in comparative psychology and ethology, coupled with ongoing archaeological discoveries and recent advances in genomics, have contributed to the current explosion of scientific interest in dogs (Canis lupus familiaris). The long and complex evolution of a human-dog relationship is explored from the differing perspectives of ethology, cognitive sciences, evolutionary anthropology, archaeology, and paleoanthropology. Our understanding of dogs is again shedding light on human cognitive evolution and the complex, and at times controversial, process of domestication.  相似文献   
3.
The study implements the performance-based analysis and design methodology to assess the seismic vulnerability of a coal-fired power plant and to optimally design its equivalent pendulum-type tuned mass damper system such that the direct losses are minimized. A building-specific total loss ratio is developed to link the component level losses with the total repair cost of the original structure. The optimal system configuration is finally derived for cases with the minimum loss. The study demonstrates a systematic way of achieving the optimal pendulum-type tuned mass damper design with considerations of uncertainties in earthquake inputs and the combined component level damages.  相似文献   
4.
在植物对土遗址作用的研究中,鲜有就真实的遗址来展开调查,以及讨论植物给土遗址带来的负作用及其机理。为此,本研究选取西安地区大型土遗址秦阿房宫为研究对象,利用现场调查结合样带法、图像分析法并采集土样,开展对遗址区植物分布、根系产生的裂隙和土壤环境的研究。结果表明:造成土遗址病害现象的主要原因为植物根系作用,加之雨蚀、风化作用及人为破坏的叠加作用,使遗址保存面临严重威胁;其中酸枣、臭椿等萌生树种所产生的根劈裂隙及植物根系对土壤环境的影响十分明显。现存土遗址由植物以及风雨作用而引发的主要病害,其类型包含了边缘夯土的基础掏蚀、洞穴遗存、开裂坍塌、冲沟发育、表面剥蚀,这些是阿房宫遗址面临的主要威胁,也是半干旱地区土遗址存在的特有问题。研究结果既有助于揭示植被对土遗址的作用机理,又能为土遗址保护的植物选择提供理论依据和技术支撑。  相似文献   
5.
The chemical compositions and microstructures of some 35 faience objects from Egypt spanning the period from the Middle Kingdom through to the 22nd dynasty are determined using analytical scanning electron microscopy. Replicate faience beads glazed in the laboratory using the efflorescence and cementation methods are similarly investigated. In efflorescence glazing, there appears to be preferential efflorescence of soda over potash, and in cementation glazing, preferential take up of potash over soda into the glaze. These data are then used to try to infer the raw materials and methods of glazing employed in the production of the ancient faience. The glaze/glass phases present in the faience differ significantly in composition from that of New Kingdom glass. This could be due either to the use of different plant ashes or to changes in the composition of the plant ashes during the production of faience and/or glass. Although it is only rarely possible to determine with certainty whether ancient faience was glazed by efflorescence, cementation or application, the observed microstructures provide an indication of the approach adopted to achieve desired performance characteristics such as strength.  相似文献   
6.
Our blind tests are distinctive for they were conducted on replicated stone tools used for a variety of tasks that included the processing of animal remains and plants. The analyst was required to differentiate an array of residues from microscopic morphological characteristics, using light microscopy. The original aim of our first tests was to assess the analyst's ability to identify a variety of plant and animal residues, but issues and problems that arose during the testing process made it clear that greater value might be gained from the lessons that we learnt about methodology and the direction for future micro-residue research. We show that problems identified during our first tests stimulated research. Amongst other things, we learnt to distinguish plant and animal remains more confidently than previously. Our residue analyses are firmly embedded in wider archaeological research and our tests help to explain why there are sometimes contradictions between the evidence from archaeologically recovered remains and residues on stone tools. A further outcome of the tests is that we have adopted a multi-stranded approach that provides a cautious, but secure strategy for identifying and interpreting use-residues. Our studies of contaminants through replications have also been invaluable for distinguishing incidental residues from use-related residues.  相似文献   
7.
The main objective of this paper is to suggest an alternative approach for the investigation of domestication in the Levant. First, basic data regarding domestication in the Levant are presented. Then the various traditional approaches towards domestication in the prehistoric Levant, labeled (1) environmental, (2) social and anthropological, and (3) cognitive, are briefly reviewed. This discussion forms the basis for a proposal of a “holistic approach,” in which domestication is regarded as a long-term, multidimensional and multirelational phenomenon, including many elements—such as plants, animals, humans, material culture and ancestors—with increasing human manipulation of these various constituents. After a presentation of the theoretical framework, a growth metaphor is used to reconstruct the process of domestication (ca. 20,000–6500 B.P.) as a number of phases: (1) germination in the Kebaran; (2) development in the Early Natufian; (3) retreat/dormancy in the Late/Final Natufian; (4) growth in the Pre-Pottery Neolithic A; (5) florescence in the Early- and Middle Pre-Pottery Neolithic B: (6) further development in the Late Pre-Pottery Neolithic B; (7) dispersal in the Final Pre-Pottery Neolithic B and the Pottery Neolithic. In each of these phases, relations between the various elements are dealt with, special attention being paid to symbolical relations, as evidenced by “art” and ritual.  相似文献   
8.
Food production originated in various ways in different parts of the world. Plant domestication with the adoption of agriculture has been successful in some areas, but not in others, where animal domestication with nomadic pastoralism proved to be more effective. Likewise, the preceding phases of pre-adaptation and development of a broad spectrum of wild resource exploitation followed different pathways, according to the locally available resources, climatic and geographic conditions, and social organizations. Northern Africa greatly contributed to the understanding of the origin of food production under preconditions that differed from those in the Fertile Crescent. Apart from a narrow strip along the Nile valley, northern African lands are arid and scarcely productive for agriculture. Nevertheless, early studies interpreted northern African archaeological records of the Early and Middle Holocene according to the traditional north-western Mediterranean and Near Eastern frames of reference. Consequently, terms such as Epipalaeolithic, Mesolithic, and Neolithic were uncritically applied to northern African contexts. This paper compares and discusses the evidence for food production in the Near East and northern Africa, considering the question of introduction or local breeds of domesticated animals in the Maghreb and the Sahara. It then reviews the relevant data for long-held diffusionist models of pastoralism into Africa to provide a different perspective and the proper means of interpretation of the northern African archaeological records. Finally, it examines some recent findings from the Tadrart Acacus, in the Libyan Sahara, which contribute to clarification of distinctive African pathways and propose an alternative model for the beginnings of food production.  相似文献   
9.
In many parts of Eurasia, the Middle East and Southeast Asia where native wild suids occur, it is notoriously difficult to differentiate these from introduced domestic pigs in the prehistoric archaeological record. Yet, correct identification of the initial appearance or introduction of domestic pigs (Sus scrofa ) is essential for determining the timing for the transition from purely hunting to the adoption of managed animal populations within different regions across the globe. In a recent review of techniques used by zooarchaeologists to distinguish between domestic and wild pig populations, the analysts concluded that the most reliable method was metrical analyses, when the data produce a clear two‐population pattern, one domestic, the other wild. In this study, we demonstrate how linear metrics are an effective tool, albeit at different levels of confidence, for differentiating the native and endemic species of Philippine pig from S. scrofa , both within modern contemporary assemblages, and the archaeological record. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
10.
Body mass is a key biometric that is useful in interpreting many aspects of an animal's life history. For many species, including dogs and wolves, methods for estimating body mass are not well developed. This paper assesses the utility of using limb dimensions to predict body mass in dogs and North American wolves. Regression analyses are utilized here to explore the correlations between limb dimensions and body masses of modern dogs and wolves, all of known body mass at death. These analyses reveal that a number of limb end dimensions are correlated with body mass in both dogs and wolves. Regression formulae generated through the analyses appear to allow body masses to be predicted with relatively small margins of error, often less than 10%. Formulae are calculated for groups with and without juveniles. In some cases, the dimensions of the juvenile specimens plot distinctly from those of adults, indicating that regression formulae specifically for juvenile canids may be needed. The strength of the limb dimension correlations is then compared with that of regression formulae for dog and wolf cranio‐mandibular dimensions. For the dogs, the cranio‐mandibular dimensions appear to slightly out‐perform the limb element dimensions in predicting body mass. The wolf limb dimensions, however, always appear to provide better predictions of body mass than do the skull dimensions. The newly developed regression formulae are applied to several Middle Holocene dog skeletons from Siberia for which previous body mass estimates are available, the latter based on cranial dimensions. These two sets of estimates are then compared. The overall results of our study indicate the need for further research, particularly with larger sample sizes, including more juvenile specimens. We also argue that work on body size estimation in single dog breeds may be warranted in some cases. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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