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41.
Chickens were part of the Lapita cultural complex, transported into and through the Pacific by prehistoric colonists; as such they can be used as a proxy for tracking prehistoric migration and interaction. The Lapita site of Teouma in Vanuatu is well known for the recovery of complete dentate stamped pots and a cemetery containing the largest collection of Lapita period skeletons ever found. Chicken bones recovered from these excavations provide the first ancient DNA sequences from any commensal organism directly associated with a Lapita context. The ancient mtDNA sequences obtained from two Teouma chicken bones are compared with previously published archaeologically derived ancient DNA sequences to extend our understanding of the spread of chickens in Pacific prehistory. The results also show that the haplogroup E signature was present in very early populations of chickens transported into Remote Oceania. This study also adds to the suite of available data relating to isotopic signatures for commensal animals during the early settlement of Vanuatu and may reveal a different diet for Teouma chickens than those from other early prehistoric assemblages in the Pacific.  相似文献   
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43.
One of the defining features of the material culture of space exploration is the fact that much of it is “out there”: in orbit around celestial bodies and on planetary surfaces. In outer space, we have to rethink the meaning of place. Cartesian coordinates must be replaced with equations of motion to describe the ceaseless movement of heavenly objects in relation to centres of gravity. Archaeological sites in space are not solid condensations of artefacts, hundreds or thousands of years compressed into layers perhaps only centimetres deep. The materials of an archaeological deposit become rather a cloud or swarm. But for both Earth and space, gravity is the structuring force. In this paper I want to reconceptualise archaeological sites according to their position in the gravity well, using dynamical systems and Riemann surfaces. I then consider the Mir space station as an example of a site existing simultaneously on Earth and in orbit, as a preliminary excursion towards a frame of reference that can be used to effectively conduct an archaeology in outer space.  相似文献   
44.
The range of stones cast by slings used in the past is debated. In the Central Andes, slings are asserted to be important weapons of prehispanic war, and have been recovered archaeologically. Rolled river cobbles and stones presumed to be slingstones found at fortified hilltop archaeological sites are presented as evidence that slings were used at these fortifications. Yet sling use has not been adequately tested at hillforts. Experiments conducted in Europe by a novice slinger have attempted to illuminate the range of sling cast stones at ancient hillforts. Data acquired from native slingers is necessary to more accurately assess distances achieved by projectiles launched by slings. We present data from sling experiments carried out in Puno, Perú among Quechua-speaking herders who are experienced slingers. The results demonstrate that a prior model of the maximum theoretical distance of sling cast stones underestimates their range. Results also show significant differences in the use of slings by men and women, and by different age groups. These new data permit a better approximation of warfare that has bearing on our interpretation of fortified sites.  相似文献   
45.
Despite uniform geochemistry 40Ar/39Ar ages of 0.6, 1.25, and 1.3 Ma on obsidians from a source flow (Worja) and from archeological artifacts at the sites of Kulkuletti (near Gademotta, Ethiopia) have been interpreted to suggest that they derive from different source flows of different ages. A further suggestion is that the magmatic source of the obsidian flows was chemically homogeneous between 1.3 Ma and 0.6 Ma. Chemical analysis of these obsidians indeed suggests that they derive from a single flow. Reexamination of the argon isotopic data reveals that argon isotopes may have been fractionated within the flow, so that the assumption of an atmospheric 40Ar/36Ar ratio of 295.5 is inappropriate to use for computing ages. Three groups of data are apparent, and internally all yield ages near 1.3 Ma if the intercept value for 40Ar/36Ar from an isotope correlation plot is used for computation instead of using the atmospheric ratio. The Soret thermal diffusion effect provides a possible mechanism of fractionation of argon within the obsidian flow that is of approximately the right magnitude to explain the observations by in-diffusion of already fractionated atmospheric argon.  相似文献   
46.
Results of analyses of the photoperiod response gene (PPD-H1) and simple sequence repeats (SSRs) in modern landraces of cultivated barley were used as evidence for the mechanism of agricultural spread in Neolithic Europe. In particular, we explored the usefulness of considering adaptive genes as indicators of past selective pressures acting on crops, during their spread through Europe. In some areas, such as the Alpine region, Britain and Scandinavia, we have evidence to suggest that the adaptation of crops to certain climatic conditions may have contributed to the timing of agricultural spread. At the northern fringes of Europe, and in higher altitude locations in central Europe, the introduction of more suitably adapted cereals may have facilitated successful agriculture to trigger agricultural expansion. This research opens up the possibility of investigating other genetic adaptations to climate, which would permit a fuller evaluation of the relative contributions of climate/crop and forager/farmer interactions in the process of agricultural spread.  相似文献   
47.
Excavations at Cladh Hallan, a Bronze Age-Iron Age settlement on South Uist in the Outer Hebrides off the west coast of Scotland, revealed the skeletons of two adults, a sub-adult and a child buried beneath the foundations of three roundhouses. Osteological and isotopic evidence has shown that the male adult skeleton is a composite made up of parts of at least three different individuals. To test the hypothesis that the female skeleton was also a composite we examined ancient DNA from four of its components: the skull, mandible, right humerus and right femur. Seven polymerase chain reactions (PCRs) were attempted, these covering positions 15,996–16,420, 16–132 and 232–368 of the mitochondrial DNA hypervariable I and II regions. Three PCRs were successful for each sample and a total of 55 sequences were obtained from the cloned products. After exclusion of possible contaminating sequences, the remaining 34 were compared. It was concluded that the mandible, humerus and femur come from different individuals. Insufficient data were obtained to draw conclusions regarding the origin of the skull. The presence of two composite skeletons at Cladh Hallan indicates that the merging of identities may have been a deliberate act, perhaps designed to amalgamate different ancestries into a single lineage.  相似文献   
48.
This article is part of a review symposium of Sheila Cavanagh's book Queering bathrooms: gender, sexuality and the hygienic imagination, 2010, Toronto, University of Toronto Press, 295 pp., £19.94 (paperback), ISBN 978-1-4426-10736  相似文献   
49.
ABSTRACT The headcount ratio in Chile has declined from 40 percent to 14 percent since 1987. However, most analysis of this reduction uses national and regional poverty statistics. In contrast, we employ poverty mapping methodologies to find heterogeneity in the effectiveness of transfers across counties. To better understand this variation, we explore the roles of characteristics of the local population, structural features of the county, and geography. The greatest reductions in poverty occur in rural households, yet population characteristics and geography are also important. These findings suggest that targeting at low levels of aggregation can deliver further reductions in poverty.  相似文献   
50.
The aim of this paper is to suggest an analytical framework through which the complex question of hospital closure and local protest can be further explored. The significance of this area of study lies with the extraordinary events that surrounded a campaign to save the Kidderminster General Hospital from downsizing. Whilst the hospital was not saved, the local campaign committee organizing the protest took their fight into the political arena and were successful in gaining a parliamentary voice in the 2001 general elections. Such an achievement has had considerable political implications, however, the question asked here is how might we begin to interpret the events that took place. To this end, the paper draws on current geographical literature in an attempt to construct a framework that accounts for both national policy debates and the local context within which such campaigns emerge.  相似文献   
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