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1.
Total pore volume and pore size distribution are indicators of the degree of post‐mortem modification of bone. Direct measurements of pore size distribution in archaeological bones using mercury intrusion porosimetry (HgIP) and back scattered scanning electron microscopy (BSE‐SEM) reveal a common pattern in the changes seen in degraded bone as compared to modern samples. The estimates of pore size distribution from HgIP and direct measurement from the BSE‐SEM images show remarkable correspondence. The coupling of these two independent approaches has allowed the diagenetic porosity changes in human archaeological bone in the >0.01 µm range to be directly imaged, and their relationship to pre‐existing physiological pores to be explored. The increase in porosity in the archaeological bones is restricted to two discrete pore ranges. The smaller of these two ranges (0.007–0.1 µm) lies in the range of the collagen fibril (0.1 µm diameter) and is presumably formed by the loss of collagen, whereas the larger pore size distribution is evidence of direct microbial alteration of the bone. HgIP has great potential for the characterization of microbial and chemical alteration of bone. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

2.
Many archaeological bones display a heterogeneous degradation pattern. Highly degraded bones could contain pockets of well‐preserved bone, harbouring good quality DNA. This dichotomy may explain why the relationships between global bone preservation parameters such as histological integrity, bone mineral crystallinity or collagen yield, and bulk DNA preservation/amplification success rate have been found to be at best, weak to moderate. In this pilot study, we explore whether or not a more localised approach will highlight a stronger relationship between diagenetic parameters and DNA preservation. This study includes a detailed histological characterisation of bone diagenesis in sub‐areas of three bone samples. Regions of the same bone, which displayed differential degrees of preservation or type of diagenesis were sampled for further analysis and both genetic (small scale Illumina MiSeq sequencing) and chemical (Fourier‐transform infrared spectrometric analysis) analyses were performed. The aim was to investigate how bone diagenetic processes relate to DNA preservation at a higher resolution than in previous studies. This is key in order to improve DNA analytical success rates. The expected relationship between bone and DNA preservation (retrieved endogenous DNA) was observed and the results corroborate previous work that DNA preservation is linked to the integrity of bone collagen and mineral. The results further suggest that non‐biological diagenetic alterations such as etching and the presence of mineral infiltrations and inclusions have a negative effect on DNA preservation/extraction. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

3.
Despite a growing awareness of the wide range of information that can be provided by detailed analyses of burned bone from archaeological contexts, such analyses are still relatively uncommon. This paper focuses on the behavioral and taphonomic implications of burned bone from the Middle Stone Age (MSA) site of Sibudu Cave (South Africa), reporting on the analysis of a large sample (>377,000 fragments) of bone recovered from the Howieson’s Poort (HP) and post-HP MSA deposits at the site. Faunal remains were initially sorted into burning categories based on changes in color; microscopic analyses focused on the optical properties of the bone matrix (degree of preservation of the bone structure, reflectance and fluorescence) indicated that the color is a valid indicator of thermally altered bone in the Sibudu assemblage. The association of burned bone with hearths, the intensity of burning damage, and the sheer quantity of thermally altered bone suggests that the bone was not burned primarily as a result of natural fires. We propose that the high incidence of burned bone primarily reflects two types of site maintenance activities: first, the discarding of bone into fire as a means of disposing of food waste (as also argued by Cain [2005, Using burned animal bone to look at Middle Stone Age occupation and behavior. J. Archaeol. Sci. 32, 873–884], for a smaller sample of material from the post-HP and late MSA deposits at the site), and second, the incidental burning of bone on/near the surface during the periodic burning of plant-based bedding. In considering the taphonomic implications of the burned bone, we demonstrate that calcined bone is in fact more heavily fragmented than unburnt or moderately burned bone. Furthermore, cortical preservation was negatively correlated with the intensity of burning damage, which has implications for the study of surface modifications. These results indicate the importance of conducting thorough taphonomic analyses prior to making comparisons between units that show differing degrees or intensities of burning damage.  相似文献   

4.
J. H. Bell  B. B. Bowen 《Geofluids》2014,14(3):251-265
Differential cement mineralogy is influenced by depositional textures, structural deformation, pore fluid chemistry, and ultimately influences landscape evolution by introducing heterogeneities in erodibility. In Southern Utah, the region West of the Kaibab uplift known as Mollies Nipple (Mollies) in Grand Staircase‐Escalante National Monument exhibits a complex history of fluid–sediment interactions, which has resulted in a localized zone of anomalous diagenetic iron sulfate (jarosite) mineralogy in a well‐exposed dune–interdune deposit within the Navajo Sandstone. Mineralogy and geochemistry of cements within this region are examined using reflectance and imaging spectroscopy, field investigations, microscopy, and whole‐rock geochemical analyses. These data show that the in‐situ jarosite cement is localized to a plane along the highest ridge of the butte, providing an armor along with other secondary cements, which controls the butte's geomorphic evolution. The jarosite cement is associated with other mineralogies suggesting that the sulfate was one of the latest fluid‐related precipitates in the paragenetic sequence. It was preceded by a regional bleaching event, precipitation of clay cements, some localized concretionary iron oxide precipitation, and formation of deformation bands. At least one generation of dense iron oxide mineralization is associated with cataclastic brittle deformation predating the sulfate precipitation. Trace element geochemistry of cements shows certain metal oxide populations associated with extremely high (>2000 ppm) arsenic values. We interpret the combination of spatial mineral distribution, observed paragenetic sequence, and trace element geochemistry to suggest this region experienced acid sulfate diagenesis along fracture‐controlled fluid conduits related to weathering of proximal, unidentified, sulfides, or H2S associated with deep source beds. Jarosite is highly soluble, and its presence suggests that abundant fluid flow has not occurred in this region since its formation. This terminal cement‐forming event must have occurred prior to sandstone exhumation and erosion to form the current extreme landscape at Mollies. This site exhibits the influence that fluid geochemistry, sedimentary mineralogy, and structural fabric have on geomorphic evolution.  相似文献   

5.
This research focuses on scale pattern and cross sectional morphology of hair to identify an expanded sample of fossil hairs from Parahyaena brunnea coprolites from Gladysvale cave in the Sterkfontein Valley, South Africa. The coprolites are part of a brown hyaena latrine preserved in calcified cave sediment dated to the Middle Pleistocene (257–195 ka). Forty-eight fossil hairs were extracted from 12 coprolites using fine tweezers and a binocular microscope, and examined using a scanning electron microscope. Hair identification was based on consultation of standard guides to hair identification and comparison with our own collection of samples of guard hairs from 15 previously undocumented taxa of indigenous southern African mammals. Samples were taken from the back of pelts curated at the Johannesburg Zoo and Ditsong National Museum of Natural History (formerly Transvaal Museum, Pretoria). Based on the fossil hairs identified here, this research has established that brown hyaenas shared the Sterkfontein Valley with hominins, warthog, impala, zebra and kudu. Apart from humans, these animals are associated with savanna grasslands, much like the Highveld environment of today. These findings support the previous tentative identification of fossil human hair in the coprolites, provide a new source of information on the local Middle Pleistocene fossil mammal community, and insight into the environment in which archaic and emerging modern humans in the interior of the African subcontinent lived.  相似文献   

6.
Ancient bones in a good preservation state, ascertained by microscopic techniques, conserve extracellular matrix proteins over thousands of years. With new techniques, intact extracellular matrix proteins from ancient bones and teeth are extracted and separated by one‐dimensional and two‐dimensional electrophoresis. Proteins were identified in Western blots by special antibodies against different human extracellular matrix (ECM) molecules of bone. We have confirmed different types of ECM human bone molecules such as osteonectin, osteopontin, and alkaline phosphatase with specific antibodies in human bone samples from different age groups. Additionally, we selected bone samples from different cultural time periods, such as the Middle Ages, the Bronze Age and the Late Pre‐Pottery Neolithic Phase (PPNB), and teeth from individuals from the Early Middle Ages and from the Late PPNB. The survival of intact extracellular matrix proteins in ancient bones and teeth dating from recent times to the Late PPNB, and reliable techniques to identify these proteins, present a great challenge to further research. A Match Set with PD‐Quest 7.2 shows that only 16% of protein spots in the teeth are also found in the bone of the same individual. In combination with the results of macro‐ and microscopic investigation, biochemical techniques will help us in obtaining a better understanding of bone and teeth in health and disease. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

7.
8.
M. Wojcieszak  L. Wadley 《Archaeometry》2018,60(5):1062-1076
Micro‐residue analysis of stone tools is generally performed with optical light microscopy and the visual observations are then compared with experimental, replicated pieces. This paper complements such archaeological research by providing physico‐chemical evidence. Raman spectroscopy and scanning electron microscopy have been used to confirm the presence of hematite on red‐stained medial and proximal parts of 71 000‐year‐old Still Bay bifacial tools from Sibudu Cave. Our results confirm the conclusion from optical light microscopy that the tools were hafted with an ochre‐loaded adhesive. However, we point to some instances when hematite residues are incidental or may be inclusions in the rock used to make the stone tools.  相似文献   

9.
Living bone sequesters environmental lead (Pb) from both inhalation and ingestion, providing a record of Pb exposure over a lifetime. Questions about the effects of diagenesis and how to remove them have hampered most isotopic and elemental determinations. As a result, researchers often restrict their analyses to tooth enamel, despite its limitations. We report Pb isotopes in teeth and bones in a frontier population of 15 individuals from a late 19th century mental hospital graveyard in Pueblo, Colorado, a town active at that time in the smelting of ores. Analysis of lead isotopes sequestered in healing bone from rib fractures gives an isotopic fingerprint from the last few months of individual's lives. When bone tissues or teeth from different stages of life are analysed, life history trajectories such as migration routes can be developed which are partially self‐correcting for diagenesis. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

10.
Trauma analysis in archaeological human remains can aid our understanding of cultural practices, socio‐economic status, environmental and social conditions, and even aspects of a person's occupation. For this reason, fracture patterns and frequencies can be useful in making inferences about the environment people lived and worked in. This is especially true for the 20th century mining industry where unskilled migrant labourers were often subjected to harsh working and living conditions. In this study, the skeletal remains of 36 Chinese indentured mine labourers, who worked and died on the Witwatersrand mines, South Africa, during the period ad 1904–1910, were assessed for evidence of trauma. Historical information suggests that these indentured Chinese labourers were unfamiliar with the workings of deep‐level mines and as a result sustained many work‐related injuries. Analyses suggest low frequencies of ante‐mortem trauma. In the few instances where they occurred, these healed fractures most probably reflect injuries already sustained in China, some time before Chinese indentured employment on the Witwatersrand mines. A high frequency of traumatic lesions, specifically peri‐mortem fractures, however, suggests a drastic shift in their working environment attesting to the hazardous working conditions associated with deep‐level mining in the early 20th century. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

11.
This work presents new taphonomic data on bone modification by suids, including domestic pig, wild and hybrid boars. The intense modification undergone by bones from animals smaller than 100 kg is shown, together with a more moderate modification on bones from larger animals. Both the ravaging pattern (with preferential deletion of cancellous tissue) and the tooth‐marking frequencies are similar to those documented among hyenas and dogs when having primary access to complete bones. A dual‐patterned experimental model consisting of the interaction of humans and suids was also considered. Here it is shown how suid modification of hammerstone‐broken bone assemblages is different from that documented among canids and hyaenids, as experimentally replicated. These results increase the number of non‐anthropogenic bone‐modifying agents and posit new issues on equifinality processes. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

12.
Small fragments of cremated human bone, clearly representing numerous individuals, were found in a stratified Neolithic context in a small cave at Jebel Faya in the Central Region of the Emirate of Sharjah, United Arab Emirates. With radiocarbon dates between 6500 and 5800 cal BC, they are among the earliest well‐documented cases of cremations in south‐west Asia. Taxonomic identification of the small burned bone fragments is based on morphological and histological analysis. The deposits are to date the oldest human remains found in south‐east Arabia and represent a phase during the Middle Neolithic for which no other types of burials have yet been documented.  相似文献   

13.
The persistence of the black colour in magnetite‐containing paints in polychrome ceramics of the Argentine North‐West processed under conditions considered as oxidant has generated questions about ancient production technologies. In this work, the thermal oxidation reaction of magnetite to hematite under different temperatures, atmospheres and physicochemical characteristics of the materials is experimentally evaluated. The causes of this behaviour are elucidated, and it is concluded that in the archaeological context, a double‐firing process was not necessary to achieve the coexistence of different colours.  相似文献   

14.
This paper examines the health status of a rural African community during the emergence of Westernisation. A total of 157 skeletons, which included 120 adults (55 males and 51 females), 37 juveniles, and 14 individuals of unknown age, were analysed. Date of death ranged from 1910 to 1999, with the majority of individuals (52%) being buried after 1960. The bones were examined for infectious diseases, trauma and degenerative changes. More than half of the individuals in the sample had no pathological lesions on their skeletal remains. No cribra orbitalia was present. One case of leprosy and three cases of osteomyelitis were recorded. The most common findings were osteophytes on the vertebral bodies (syndesmophytes) (17%) and osteoarthritis (7%). The low occurrence of chronic disease is unexpected given that malaria was endemic and intestinal worms were common. Explanations for these results include adequate intake of iron from dietary sources, death from acute infectious diseases, administration of antibiotics, and poor preservation of adult skeletal remains. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

15.
H. Chu  G. Chi  I‐M. Chou 《Geofluids》2016,16(3):518-532
Fluid inclusions of the H2O‐NaCl‐CaCl2 system are notorious for their metastable behavior during cooling and heating processes, which can render microthermometric measurement impossible or difficult and interpretation of the results ambiguous. This study addresses these problems through detailed microscopic examination of synthetic solutions during cooling and warming runs, development of methods to enhance nucleation of hydrates, and comparison of microthermometric results with different degrees of metastability with values predicted for stable conditions. Synthetic H2O‐NaCl‐CaCl2 solutions with different NaCl/(NaCl + CaCl2) ratios were prepared and loaded in fused silica capillaries and glass‐sandwiched films for microthermometric studies; pure solutions were used with the capillaries to simulate fluid inclusions, whereas alumina powder was added in the solutions to facilitate ice and hydrate crystallization in the sandwiched samples. The phase changes observed and the microthermometric data obtained in this study have led to the following conclusions that have important implications for fluid inclusion studies: (i) most H2O‐NaCl‐CaCl2 inclusions that appear to be completely frozen in the first cooling run to ?185°C actually contain large amounts of residual solution, as also reported in some previous studies; (ii) inability of H2O‐NaCl‐CaCl2 inclusions to freeze completely may be related to their composition (low NaCl/(NaCl + CaCl2) ratios) and lack of solid particles; (iii) crystallization of hydrates, which is important for cryogenic Raman spectroscopic studies of fluid inclusion composition, can be greatly enhanced by finding an optimum combination of cooling and warming rates and temperatures; and (iv) even if an inclusion is not completely frozen, the melting temperatures of hydrohalite and ice are still valid for estimating the fluid composition.  相似文献   

16.
Dental pathologies and enamel defects in East Asian hominins have rarely been reported. Here, we systematically document and describe a suite of enamel defects in the Xujiayao juvenile maxilla, an East Asian hominin from the early Late Pleistocene that may represent an unknown hominin lineage. In addition, we determine the chronology of growth disruptions represented by matched linear enamel hypoplasias, evaluate the long‐held hypothesis that the large brownish pit on the I1 is evidence of dental fluorosis and assess the utility of micro‐computed tomography (micro‐CT) techniques in analyzing enamel defects. With the use of binocular microscopy, scanning electron microscopy (SEM) and micro‐CT imaging techniques, the Xujiayao teeth were found to exhibit a high number of pit‐form defects seldom seen in the fossil record. By matching the timing of linear enamel hyperplasia across multiple teeth, a minimum of five developmental disruptions were identified, indicating that the Xujiayao juvenile experienced several growth disturbances during its short lifespan. Our SEM and micro‐CT analyses suggest that the large pit on the I1 is an enamel hypoplasia due to its morphology and pre‐eruptive enamel thinning. It is not a post‐eruptive fluorotic pit, and there is no evidence of chalkiness or opacity associated with dental fluorosis. The micro‐CT technique made it possible to verify the presence of enamel hypoplasia and to more precisely quantify defect dimensions, especially in unerupted teeth and shallow hypoplasias that are difficult to detect by binocular microscopy or SEM. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

17.
We studied interrelationships among age, sex, and cross‐sectional cortical bone dimensions using quantitative computed tomography (QCT) scans of metatarsal bones of 180 moose (Alces alces) that died in Isle Royale National Park, Michigan. As a large‐bodied quadruped with demanding ecological constraints on movement and behaviour, a moose experiences different weight‐bearing and mechanical stressors than humans, to whom most existing studies of mechanical adaptations of bone pertain. In moose, both sexes showed significant subperiosteal expansion and an increase in medullary area, with an overall increase in cortical bone area over time. Female moose did not exhibit cortical thinning or reduction in cross‐sectional area with age, rather they showed an increase in cortical bone area with periosteal apposition exceeding endosteal resorption, similar to the males. We also found that moose undergo changes in bone geometry through remodelling of bone similar to humans, suggesting a compensatory mechanism for increasing bone strength under conditions of decline in bone mineral density with age. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

18.
The life of Maria Dlamini, a contract cleaner at the University of the Witwatersrand, is used to explore continuities and discontinuities between the apartheid labour regime and the neoliberal, post‐apartheid order in South Africa. As South African institutions have adopted neoliberal market strategies, the growth in the contracting‐out of cleaning has intensified work and reduced wages and benefits for many workers. Significantly, as was the case with the migrant labor system under apartheid, it has also increasingly displaced the burden of social reproduction onto the households and communities of the working poor. Whereas the racial spatial order under apartheid was dictated by national‐level political decisions, through use of the concept of “boundary drawing”, we show how the language of the market justifies new exclusions based upon the micro‐politics of the “rational” restructuring of institutions such as universities.  相似文献   

19.
Primary questions regarding the foraging behaviour of the first hunter–gatherers who colonized the New World are how they found, procured and utilized high‐quality raw materials for manufacturing stone tools. In this paper, we present evidence from the late Pleistocene site of Cueva Bautista in the highlands of south‐western Bolivia, which demonstrates that a substantial portion of the recovered stone tool assemblage originated in Cerro Kaskio, a recently discovered obsidian source located 15 km south‐west of the site. In addition to describing the geological and geochronological setting, we provide the first geochemical characterization of the Cerro Kaskio source by means of instrumental neutron activation analysis and energy‐dispersive X‐ray fluorescence. Supported on the technological analysis and archaeometric sourcing of the obsidian lithics found in Cueva Bautista, we discuss the nature of the procurement strategies practised by the earliest mobile hunter–gatherers who explored and colonized the Andean highlands. We conclude that opportunistic lithic resource procurement was probably an important component of the first foraging societies that explored the highland Andes.  相似文献   

20.
In response to its constitutional commitments and social welfare provisions in the era of democracy, the post‐apartheid South African state is increasingly called upon to provide for the lives and livelihoods of its citizens. These demands have intensified amid escalating joblessness and the highest numbers of people living with HIV worldwide. Over the past decade, antiretroviral treatment (ART) has been incorporated into an ever‐expanding welfare bureaucracy, in which access to state assistance is mediated by the collection and monitoring of biometric, bureaucratic data. Drawing on 18 months of ethnographic research in the Eastern Cape, this article explores how state documents bring young people on ART into an ambiguous relationship with the state — one that is at once subordinating and enabling. While social research on ART addresses both the empowering and coercive aspects of treatment taking, less attention has been given to how these modes of participation might be mutually constitutive. In this article, the authors examine how the same technologies that discipline youth on ART might also support and protect them; how welfare dependencies entail paradoxical forms of agency; and how the state's ability to control and to ‘care for’ citizens might be reciprocally dependent.  相似文献   

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