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11.
Post‐mortem distortion resulting from the pressure of overlying sediments (i.e. grave backfill) is one of the taphonomic factors capable of altering the geometry of buried and subsequently recovered skeletal remains. If pressure distortion is a frequent occurrence, it could systematically flaw the outcome of an anthropological examination. To study the patterns of post‐mortem distortion in buried crania and shape alterations associated with a specimen's in situ position, 46 male crania recovered from an Old Slavic graveyard (Pohansko, Czech Republic) were analysed together with control specimens from four modern European osteological collections (N = 207) using geometric morphometrics. The results indicate a common pattern of shape change in buried skulls associated with their in situ orientation. However, as the overall shape variation between the Old Slavic crania (which, with their tendency towards longer, narrower shapes differed markedly from the modern Czech crania) oriented in situ on their back and side reflects the duality of dolichocranial and brachycranial forms, it seems likely that the in situ positioning of the crania stemmed from their original morphology. The lack of substantial effect of the in situ orientation on the cranial morphology is associated with a larger cranial size and a tendency for sturdiness in the Old Slavic subsample. Both of these characteristics are likely to be contributing to the resistance of these crania to taphonomic alterations. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
12.
ABSTRACT

Changes in temperature and precipitation can affect tourist experiences. This study examines how summer park visitation has changed in response to temperature and precipitation extremes. The study goals were two-fold. The first is to introduce a framework and the second is to test it in a pilot region with four mountainous National Parks. The framework is designed to compare the vulnerability of seasonal park visitation to shifts in a combined indicator of temperature and precipitation. It uniquely considers needed measurements, and the data required to conduct an analysis. The second goal is to test it in four destinations in the U.S. Northern Rockies, including Glacier, Yellowstone, Grand Teton, and Rocky Mountain National Parks. The preliminary test reveals outlier cases of visitation under wet and dry extremes. The analysis connects time series climate and visitation data for the peak summer season from 1991–2012. Outlier analysis illustrates more change in extremely dry conditions, with four out of the six dry-year outliers resulting in a visitation decline. Whether this decline in park tourism is attributable to climate features, economic factors, or conscious management decisions, these drops have significant economic impacts: estimates of changes in visitor spending during dry years are between roughly 9 and 90 million USD. These differences may be connected to the popular activities in each park, and the extent they are dependent on weather conditions. This framework can be used to test the relationship between climate and tourism visitation in other regions, in various seasons and time frames. The work may inform the tourist sector in adjusting and planning for a range of conditions. We discuss opportunities and conclude with additional needs for understanding the mechanisms behind risk in mountain park tourism under climate extremes.  相似文献   
13.
Roc de Marsal has yielded numerous remains of Mousterian occupations, including lithics, fauna and combustion features. It was made famous by the discovery of the skeleton of a Neanderthal child. Given the need to date the sequence, TL and OSL were applied on heated flints and quartz, and OSL on unheated quartz. Chronological results combined with palaeoenvironmental data – faunal remains and micromorphological features in the sediments from the cave, pollen proxies and faunal remains from the region – allowed us to place climate variations in southwest France on a numerical time scale. Denticulate Mousterian occupations were dated to the middle of MIS 4 (65–70 ka) and Quina layers either to the very end of MIS 4 or to MIS 3. Interestingly, a faunal pattern showing a mix of red deer, roe deer and reindeer was found to have occurred during MIS 4, which was shown to be consistent with data from other similar sites in southwest France.  相似文献   
14.
We present an evolutionary model of social change in the Middle Ohio Valley during the Fort Ancient period (AD 1000–1650), primarily relying on an application of Winterhalder’s (1986) and Kelly’s (1995) evolutionary ecology model of cultural responses to environmental variability. We predict changes in social organization, political complexity, and patterns of stylistic similarity. As the environmental background for our model we employ recently published moisture data. By iteratively applying the synchronic Winterhalder–Kelly model we are able to predict a sequence of general trends that agree with much current interpretation of Fort Ancient development. Specifically, the model leads us to expect increasing village size, the development of regional traditions, and the development of leadership roles and a region-wide style Horizon around AD 1400. However, our model provides the ability to make testable predictions that deviate from the accepted cultural history and predicts that the Middle Ohio Valley and the groups referred to as Fort Ancient were far from homogenous.  相似文献   
15.
Previous research acknowledges the ancient and complex land-use history of European mountainous areas, which are characterised by a remarkable regional variability in terms of human practices and patterns of occupation during the Holocene. However, the combined palaeoenvironmental and archaeological study of highland human management at a micro-regional scale remains a largely unexplored research field, especially in the Pyrenees. A combined pollen, stomata, non-pollen palynomorphs (NPPs) and macrocharcoal study was carried out at three nearby alpine and subalpine peat basins from a relatively small territory (ca.1700 ha) at the Madriu valley (Andorra, eastern Pyrenees), following a fine spatial-resolution strategy. The purpose was to test the suitability of high altitudinal palaeoecological sequences when reconstructing past small-scale land-use variability. The palaeoecological results of those peat records are compared and further integrated with archaeological local data, and together underline the marked complexity of high mountain land-use system over the Holocene period. Main phases of micro-regional land-use and landscape variability can be distinguished from the middle Neolithic to the early Bronze Age and from the Roman Period to the Modern Era. Conversely, several phases of homogeneous landscape management are distinguishable during the early Neolithic, and from the late Bronze to the late Iron Age. Results drawn from this study show that landscape variability is not necessarily connected to topographic or climatic parameters, and underline the role of social, economical and cultural parameters in the land-use organisation and the landscape shaping of high mountain spaces since Prehistory.  相似文献   
16.
Research into the links between climatic change and hominin evolution has generated numerous hypotheses. In recent years, methodological refinement of, and increased research effort directed towards, reliable proxies for palaeoclimatic change have provided a growing body of data with which to test such hypotheses. Whilst many archaeologists are aware of these data, few are cognizant of the wealth of techniques developed by theoretical biologists over the last half-century to explicitly address the evolutionary consequences of adaptation to temporally heterogeneous environments. The current paper expands and adapts one such technique for use with empirical data, and applies it to a global palaeoclimatic record spanning the last five million years, in order to discern the potential impact of environmental heterogeneity on hominin evolution during this period. Of particular interest are the contributions of climatic change, associated with directional selection, and climatic variability, associated with selection for phenotypic plasticity. At this macro-scale, results suggest an early peak in selection for plasticity at approximately 2–2.7 mya, combined with three major shifts in directional selection at approximately 3.3–3.4, 1.4–1.5, and 0.5–0.6 mya. These results are employed to relate the fossil and archaeological records to a number of environmental hypotheses of human evolution. In particular, it is argued that the origins of the genus Homo and the spread of Oldowan technology are associated not with a major turnover pulse, but with a period of selection for phenotypic plasticity.  相似文献   
17.
Sediment accretion in ancient urban sites and tells records a combination of cultural and geomorphic processes. Urban geoarchaeology is focused on site accumulation, collapse, weathering and erosion, as constrained by architectural plans and structures. These may document settlement growth and decay, as well as environmental history, posing a multidisciplinary challenge of interactive and fluctuating processes.  相似文献   
18.
Snow cover is often measured as snow‐water equivalent (SWE), which refers to the amount of water stored in a snow pack that would be available upon melting. Snow cover and SWE represent a source of local snow‐melt release, and are sensitive to regional and global atmospheric circulation, and changes in climate. Monitoring SWE using satellite‐based passive microwave radiometry has provided nearly three decades of continuous data for North America. The availability of spatially and temporally extensive SWE data enables a better understanding of the nature of space‐time trends in snow cover, changes in these trends and linking these trends to underlying landscape and terrain characteristics. To address these interests, we quantify the spatial pattern of SWE by applying a local measure of spatial autocorrelation to 25 years of mean February SWE derived from passive microwave retrievals. Using a method for characterizing the temporal trends in the spatial pattern of SWE, temporal trends and variability in spatial autocorrelation are quantified. Results indicate that within the Canadian Prairies, extreme values of SWE are becoming more spatially coherent, with potential impacts on water availability, and hazards such as flooding. These results also highlight the need for Canadian ecological management units that consider winter conditions.  相似文献   
19.
The backward extension of a river flow record for the River Tay, based on daily water level observations from 1937–76, has created the third‐longest sensibly continuous daily flow record for any Scottish river based on direct observations. The paper describes the derivation of the record, and assesses the variability of the Tay discharge over the 60‐year period covered. Unprecedented winter, spring and flood flows in the late 1980s/1990s are reported, in the context of improving the understanding of hydroclimatic variability.  相似文献   
20.
This study applies an intra-skeletal sampling strategy to examine post-mortem alteration of archaeological human bone from west Mexico, and to reconstruct ancient diet. Human bone from the Chupicuaro culture (Mexico, Preclassic period) constitutes an ideal material with which to examine subsistence strategies because the specific hydrothermal environment in which the population lived would have provided certain food components (hydrothermal waters and carbonates) with distinct signature in Ca, Mg, F, Li, Sr, Mn, V and U values. Four to ten samples were taken from the long bones of six skeletons. Bone trace element content (Ca, P, F, Mn, Mg, Na, Li, V, Zn, Rb, Sr, Ba, Y, La, Ce, Nd, Th, U) and bone alteration parameters (crystallinity, organic matter and secondary calcite content) were analysed at the intra-skeletal level. Stable isotopic signatures (bone δ13C and δ18Ocarbonate) and histological analyses were also performed on a single bone from each individual. Results indicate that all of the skeletons were affected by post-mortem mineralogical, structural and geochemical transformations. Biological bone δ13C values seem preserved for most of the individuals but an increase in crystallinity accompanies depletion in bone δ18O values. The combination of bone alteration parameters with bone elemental content shows that in this very specific context, a widespread dissolution-recrystallisation is unlikely. Of the hydrothermal tracers, Sr, F and Li were of particular interest because their retention in living tissues is related to the amount ingested. The intra-skeletal Li content does not reveal any pattern but Li depletion is not excluded. In contrast, Sr and F show a progressive intra-skeletal diagenetic enrichment likely due to gradual diffusion–adsorption processes. The bones with the lowest concentrations in these elements are assumed to yield the best representative ante-mortem values. The signal extracted from each skeleton, a very unusually high bone Sr, F and Li content, is interpreted as reflecting the consumption of the local hydrothermal products, which are also enriched in these elements.  相似文献   
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