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1.
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   
2.
From the late Pleistocene to early Holocene in Japan, subtropical and temperate forest elements moved northwards. This affected human choices and access to food sources. More settled patterns of living spread northwards gradually, and northern hunting-gathering-fishing people began cultivating vegetables and cereal crops. This poster reports the presence of ancient starch residues on stone artefacts in Kagoshima Prefecture, southern Kyushu. The oldest residues recovered are dated by context to about 30,000 14C yr BP. If such residues can be identified, it may be possible to detect a hypothesized early phase of tropical plant movement northwards during warmer climate peaks in the late terminal Pleistocene, as well as during the long period of Holocene warming that followed. As an initial step towards identification, the morphological characteristics and condition of the starch granules are described and compared to those of other sites in early Japan.  相似文献   
3.
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   
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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   
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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   
6.
    
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   
7.
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   
8.
In the present work we attempt to recover endogenous ancient DNA from cereal grains preserved under different conditions: charred, partially charred and waterlogged. A total of 126 grains from naked wheat and 18 from barley from different sites on the Eastern Iberian Peninsula ranging from the beginning of agriculture in the region to the turn of the Common Era, were studied. Two different extraction protocols were used, a standard phenol–chloroform method and a silica-based DNA extraction procedure implemented for artificially charred seeds. Amplifications were directed to three markers: the large subunit of ribulose 1,5 biphosphate carboxylase (rbcL) and the microsatellite WCT12 in the chloroplast genome and the x and y subunits of the high molecular weight glutenin gene (Glu-1) in the nucleus. The first two were used to assess the preservation status of the samples, while with the third we tried to identify the wheat grains at species level. It was possible to obtain eleven positive amplifications in 8 partially charred seeds but only two amplifications of the Glu-1 gene from a single sample of the Early Bronze age were genome-specific. Different contamination sources were identified and reported. Cloning and alignment of sequenced clones showed a correspondence of the amplified fragment to modern wheat D genome haplotypes. This result suggests that the sample corresponds to hexaploid wheat (Triticum aestivum L.), thus being the first ancient DNA evidence to date for the cultivation of hexaploid wheat in the prehistoric agriculture of the Iberian Peninsula. Moreover, obtained results highlight contamination problems associated to the study of ancient archaeobotanical charred seeds suggest that the combination of a silica-based extraction method together with the amplification of specific targets is a good strategy for recovering endogenous ancient DNA from this kind of material.  相似文献   
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10.
The archaeobotanical research carried out in the Iron Age site of Salut (north Oman) gives insights on various interpretative scenarios: the ancient vegetation surrounding the site, oasis farming, and possible ritual practices. The landscape was dominated by dry shrublands with, among others, acacia, jujube and tamarisk that were exploited for obtaining timber and firewood. Agricultural practices mainly consisted of date palm, cereal and sesame cultivation. By comparing the datasets it was possible to assess that the date palm had various uses in this site: one hypothesis involves its offering in ceremonial practices. This third scenario suggests a new way of interpreting some of the plant remains in an archaeological site as Salut, a multipurpose site including a possibly cultic function.  相似文献   
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