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Damage generated by large and small carnivores is common in many Middle Pleistocene sites. However, identifying the predator that produces the faunal accumulations is often a difficult task. In order to recognize the main type of carnivore that acts on a faunal assemblage, a combination of several characteristics should be taken into account: taxonomic and skeletal element representation, age profiles, carnivore damage (location, frequencies and dimensions of tooth-marks, bone breakage and digested bones), degree of fragmentation and frequencies of coprolites. But, adding environmental characteristics and the ethology of non-human predators/scavengers is also important. All these aspects are applied to the faunal assemblage from the TD8 level of the Gran Dolina site (Sierra de Atapuerca, Burgos, Spain). Paleomagnetic data combined with ESR and U-series place the TD8 level at the beginning of the Middle Pleistocene, specifically circa 700 kyr ago. The TD8 level contains a large faunal accumulation primarily composed of ungulate skeletal elements, and to a lesser extent carnivore remains. This assemblage is characterized by an overrepresentation of fallow deer (Dama vallonetensis), a skeletal profile biased towards cranial remains and limb bones, diversity of ages at death, a high proportion of carnivore damage and tooth-marks of large size, and an absence of human activity. According to these data, the accumulation seems to have been produced primarily by large carnivores, possibly hyenas. This observation does not rule out the possible occasional activity by other carnivores. Nevertheless, the characteristics of the TD8 assemblage do not correlate entirely with those traditionally used to define carnivore dens. In TD8, there are (1) no immature carnivore remains (remains of just one young Mosbach wolf); (2) scarce traces related to the end stages of consumption and some anatomical connexions; (3) few coprolites; (4) high proportion of adult ungulates and; (5) high quantities of whole bones and epiphyses. From this perspective, the TD8 faunal assemblage seems to correspond to a succession of carnivore occupations that allows the development of a suite of features to identify the activities of several species of predators that may have used the cave in different ways and durations. This study aims to emphasize the importance of these analyzes in order to know the behaviour of different non-human predators/scavengers in the European Middle Pleistocene sites.  相似文献   
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In the context of an archaeological survey of the southern Argolid, Greece, studies have been carried out to elucidate the evolution of the landscape since its earliest known human occupation about 50,000 years ago. One of these studies was a detailed geological mapping of the late Quaternary alluvium and soils in the area. Dated by means of thorium-uranium disequilibria, archaeological finds, and historical information, seven periods of alluviation were identified, each of short duration relative to long intervening periods of stability and soil formation. The three earliest alluvial phases, falling before and during the last glacial interval, range from about 330,000 to 32,000 years in age. No alluviation accompanied the last glacial maximum around 20,000 years ago. In fact, a stable landscape persisted until about 4500 years ago, when debris flows and widespread aggradation in the valleys resulted from major slope destabilization and soil erosion, probably as a result of extensive land clearance in the Early Bronze Age. A subsequent stable period lasted through the many upheavals of the later Bronze Age, the Dark Ages, and the early historical period. It came to an end with a brief phase of alluviation between about 300 and 50 BC. Stability returned through the late Roman period, notwithstanding considerable expansion of the settled area. Another period of destabilization, this one marked by debris flows and hence major soil erosion, is poorly fixed in time, but probably coincides with expanded maquis clearance accompanying the resettlement of the area around AD 1000. Subsequent events of soil erosion and aggradation vary in nature and timing from one drainage to the next and, in some areas, continue today.Nature and chronology of the soil forming and alluviation events show that simple correlations with climatic events do not suffice to explain them. For the latter ones, past about 2500 BC, human activity seems to be the dominant cause, but once again the relation between cause and effect is not straightforward. Land clearing, or neglect of soil conservation efforts during economic downturns, appear to have a more devastating effect upon the landscape than do intensive land use or total land abandonment.  相似文献   
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The Cretan School of iconography is the last great flowering of the traditional Byzantine painting manner, which is however influenced by different schools and western art. Despite their historical significance, icons of the Cretan School have been rarely studied through modern chemical techniques and therefore very few information is available on the materials used by the Cretan painters. In the present investigation, the organic materials contained in several icons of the Cretan School of Iconography from the collection of the Benaki Museum, Athens, Greece, are analyzed and identified by High Performance Liquid Chromatography coupled to a Diode Array Detector (HPLC–DAD) and Gas Chromatography with Mass Spectrometry (GC–MS).The HPLC–DAD results provide support to a recently published report which showed that kermes used in “Cretan” icons of 15th century and early 16th century was replaced by cochineal which was used in icons dated after early 16th century. This trend is known for western art and it is now proved for Cretan icons, showing thus the influence of the Cretan painters by other European painting schools. Other dyes detected in the historical samples, extracted from Cretan icons are madder (possibly Rubia tinctorum L., according to HPLC profiles) and indigoid dyes. Oils, such as linseed and walnut oil, are identified in samples extracted from the seven icons tested by GC–MS. Egg yolk is identified in the extract of only one icon and animal glue, originated most likely from the gesso ground, is found in six samples. Other organic materials detected by GC–MS were wax, as well as synthetic resins, applied during conservation treatments.  相似文献   
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Interspecific variation in the equid lineage is limited when compared with other large mammal lineages, while a considerable amount of intraspecific ecomorphological variation occurs. This has led to considerable debate regarding the taxonomic status of palaeontological and archaeological equid remains. The possible confounding impact of sex and age variation on analyses of archaeological equid remains has so far remained untested. This could be especially problematic when it is unknown whether an assemblage contains more than one equid species, breed or hybrid. Here, sex and age variation in modern equid species is examined and compared to variation in Pleistocene equid assemblages from northwest Europe. Sex variation in the longbones of modern equid species was found to be lower than variation over time. Similarly, age variation in dental elements of the same species is predominantly lower than diachronic variation, although caution needs to be taken when an archaeological assemblages consists mostly of elements at a similar wear stage. To assess whether late Middle Pleistocene caballoid horse fossils should be assigned to multiple species or be considered to form a monospecific group, the coefficients of variation for measurements on fossil horse remains were compared with those for modern equid specimens. Results indicate that the fossil assemblages are similarly variable to samples of modern material. Taken as a whole, the late Middle Pleistocene caballoid horse lineage is equally variable to an assemblage of modern ponies of a variety of different breeds. This implies that the variation observed between samples dating from different parts of the Middle Pleistocene can be characterised as intraspecific variation within a single species reflecting ecomorphological adaptations to the changeable Pleistocene climate. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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