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131.
Carnivore competition, bone destruction, and bone density   总被引:1,自引:0,他引:1  
In carnivore-modified archaeofaunal assemblages it is important to evaluate the degree to which carnivores have overprinted hominin behavioral signals. To examine the signals of increased competition for discarded bone, we present controlled experimental data on 33 simulated archaeological sites subjected to secondary consumption by spotted hyenas. We examine the relationship between competition, as measured by controlled numbers of hyenas and limb bones, and resultant levels of destruction and correlations between long-bone portion survivorship and bone density. Our results indicate that levels of destruction are equivalent regardless of the numbers of hyenas or long-bones included in the experimental assemblages. Correlations between long-bone epiphyseal and near-epiphyseal portions and bone density, however, do provide an indication of the level of competition. Results from the experimental study are used to highlight divergent levels of carnivore competition for hominin-discarded bone at the Plio-Pleistocene localities FLKN-Zinjanthropus and FLKN levels 1–2 from Olduvai Gorge, Tanzania.  相似文献   
132.
The aim of this study is to present the manufacturing process developed on 3rd millennium BC white incrusted pottery from the middle Guadiana River basin (Badajoz, Spain), alongside the analytical procedure developed to determine the nature of these incrustations. The analytical procedure developed in this paper will assess the nature of these incrustations as burnt bone and in fewer cases as calcium carbonate, turning upside down the usual tendency for the Iberian Peninsula, where calcium carbonate has been the only kind of incrustation identified up until now. The analytical facilities used are: SEM-EDX, XRF microprobe, XRD and FTIR. The assessment of the nature of the incrustations as burnt bone has been a hazardous task and it has been necessary to develop a procedure using several analytical techniques and reference materials.  相似文献   
133.
We measure the bone marrow yields of mountain gazelle (Gazella gazella) carcasses to reconstruct gazelle exploitation strategies during the Epipalaeolithic periods in the southern Levant. We present experimentally derived data on the bone marrow content of seven fresh gazelle carcasses, determine the range of marrow yields among individuals of different sexes and seasons of death, and compare the new data to gazelle skeletal element abundances from five Epipalaeolithic assemblages from Israel. We found extensive variation in marrow fat content among individual gazelles. Animals with the highest marrow yields were killed in the spring while animals killed in the early autumn had lower fat contents. Nevertheless, our results suggest that gazelle marrow provided a reliable, albeit small fat resource for prehistoric foragers in all seasons. Strong relationships between bone fragmentation and marrow content demonstrate that Epipalaeolithic people preferentially processed bones with high marrow yields.  相似文献   
134.
Hyena taphonomy is of great importance to studies of hominid evolution, since these carnivore taxa have the highest potential both to produce large osseous assemblages and to modify existing hominid-accumulated assemblages throughout the Old World. The three extant hyena species (brown: Parahyaena brunnea; striped: Hyaena hyaena; and spotted: Crocuta crocuta) are all significant bone collectors and modifiers. Spotted hyenas generally have the lowest potential to accumulate osseous remains, and the rate of accumulation varies based upon the type of den. The present research examines the remains accumulated by spotted hyenas in Masai Mara Cave, Masai Mara National Reserve, Kenya. The contents of this den were collected twice by the authors, with an 11-year span interceding. The taphonomic signatures of spotted hyena interaction with bone are presented, including species and skeletal element representation, breakage patterns, tooth marks, tooth puncture, edge polish, and gastric corrosion. Other taphonomic factors examined include rodent gnawing and weathering stage. The cave den assemblage was accumulated at a rate of 30.4 identified specimens and a minimum of 4.1 prey individuals per year. In addition, the osseous remains accumulated by spotted hyenas at multiple burrow dens within the Reserve were examined for taxonomic representation and multiple taphonomic parameters. Rates of accumulation at this type of den tend to be very low, due to differential usage by spotted hyenas and the more ephemeral nature of earthen dens.  相似文献   
135.
唐墓彩绘文物的保护研究   总被引:1,自引:1,他引:0  
针对唐代墓葬的几件彩陶文物和壁画的特殊要求,选择性能优良的保护材料对彩绘文物进行加固保护。通过X-射线荧光光谱仪和分光光度仪进行彩绘文物颜料成分分析,选用浓度为2%的B72和2%的改性B72加固保护彩绘文物,测试保护后文物的表面颜料粘结性、耐水性、耐酸碱等性能,同时选用分光光度仪和粘接强度仪测试光照老化后文物的颜料颜色和粘接强度的变化。试验结果表明,文物颜料主要成分包括铅丹、铅丹和朱砂混合物、土红以及石绿;加固保护后文物的粘结性、耐水性和耐酸碱度都有所提高,且改性B72的提高程度比B72大;光照老化后改性B72保护的彩绘文物颜料主波长、色纯度和亮度变化均小于B72的变化,改性B72的粘接强度提高指数是B72的3倍之多,粘接性能优于B72。综合对比可以看出,加入紫外线吸收剂的改性B72保护材料很好地起到加固和保护彩绘文物的作用,在彩绘文物加固保护材料的选择上具有借鉴和指导意义。  相似文献   
136.
以常用的丙烯酸酯乳液AC33、B60A、MC76、SF016作为脆弱考古出土漆膜的加固剂,利用静态热机械分析仪微损、精确的特点,对加固前后漆膜的弯曲强度进行测试。根据漆膜应力应变的提升程度,对4种加固剂的保护效果进行量化评价。结合扫描电镜观察漆膜表面和剖面加固前后的孔洞、裂隙填充情况以及加固剂成膜状态,揭示其加固特点。结果发现,加固后漆膜的应力提高了56%~3 511%,应变提高了103%~3 876%,其中质量分数为20%的AC33增强效果最好,20%的B60A增韧效果最好,MC76和SF016加固效果相对较差。20%是4种加固剂的最佳使用质量浓度,此时漆膜孔洞和裂隙被完全填充,加固剂在漆膜表面形成连续的薄膜且不过量堆积。本研究将静态热机械分析仪用于极端脆弱考古出土漆膜的残余力学强度测试和加固剂保护效果的量化评估,探讨4种典型丙烯酸酯乳液对漆膜机械强度提升的规律特征,获得了较好的结果,将为考古出土糟朽漆器保护修复遴选加固剂提供科学参考。  相似文献   
137.
大雁塔和法门寺砖材保护研究   总被引:4,自引:1,他引:3  
大雁塔和法门寺塔这两座佛教名塔都表现出明显的风化现象,需要及时的给于保护。通过X-射线衍射分析、岩相显微镜分析及孔隙度的测定,分析了大雁塔和法门寺两座佛教名塔的风化特征。在此基础上,用几种不同的加固保护剂对两种砖材进行加固保护研究。通过渗透深度、孔隙度、毛细吸水和毛细渗透、持水量、透气性、水力学膨胀、等温吸附、抗压强度及酸腐蚀、冻融、热膨胀之后的强度衰减等参数分析,结果表明含氟聚合物对两种砖材具有良好的加固保护效果。  相似文献   
138.
Recently discovered bone implements from Middle Stone Age (MSA) deposits at Sibudu Cave, South Africa, confirm the existence of a bone tool industry for the Howiesons Poort (HP) technocomplex. Previously, an isolated bone point from Klasies River provided inconclusive evidence. This paper describes three bone tools: two points and the end of a polished spatula-shaped piece, from unequivocal HP layers at Sibudu Cave (with ages greater than ∼61 ka). Comparative microscopic and morphometric analysis of the Sibudu specimens together with bone tools from southern African Middle and Later Stone Age (LSA) deposits, an Iron Age occupation, nineteenth century Bushman hunter-gatherer toolkits, and bone tools used experimentally in a variety of tasks, reveals that the Sibudu polished piece has use-wear reminiscent of that on bones experimentally used to work animal hides. A slender point is consistent with a pin or needle-like implement, while a larger point, reminiscent of the single specimen from Peers Cave, parallels large un-poisoned bone arrow points from LSA, Iron Age and historical Bushman sites. Additional support for the Sibudu point having served as an arrow tip comes from backed lithics in the HP compatible with this use, and the recovery of older, larger bone and lithic points from Blombos Cave, interpreted as spear heads. If the bone point from the HP layers at Sibudu Cave is substantiated by future discoveries, this will push back the origin of bow and bone arrow technology by at least 20,000 years, and corroborate arguments in favour of the hypothesis that crucial technological innovations took place during the MSA in Africa.  相似文献   
139.
The stable hydrogen isotope ratios (δD) of bone collagen in archaeological human and animal samples demonstrate a trophic level effect, with increasing δD from herbivores to omnivores to humans, in steps of 10–30‰. In addition the archaeological sites studied (Yarnton, Eton Rowing Lake, Danebury Environs–Suddern Farm, and Windmill Hill in the UK, Balatonszárszó in Hungary, and Huari in Peru) demonstrate geographical variation in δD. The detection of manuring in prehistory by comparison of δ15N to δD values in humans and a local herbivore (cattle) is also considered. This work is the first to measure δD in a large number and range of archaeological samples, with several animal species and humans. It demonstrates unequivocally that δD is different between species in ancient material, increasing from herbivores to omnivores to carnivores.  相似文献   
140.
在战国天星观一号楚墓出土的竹简文中,有一"■"字,它涉及中国古代祭祷中的沉祭,可与商甲骨卜辞以及周礼中有关记载相互印证。  相似文献   
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