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1.
Tests for correlations between sample size and taxonomic relative abundance are commonly used in zooarchaeological analyses to determine whether observed trends in relative abundance might simply be the result of sampling error. Monte Carlo simulations designed to evaluate the utility of this method indicate that it is inadequate as a means of detecting errors resulting from the incorporation of small samples in an analysis. Among simulated sets of sample assemblages, significant correlatoins between sample size and relative abundance are distributed randomly with respect to whether or not Type II errors concerning trends in relative abundance are present, and are underrepresented in cases in which Type I errors are present. This is because the conditions that are most conducive to correlations between sample size and relative abundance are quite different from the conditions that will lead to erroneous conclusions about the presence or absence of a trend in relative abundance. An alternative chi-square-based statistical method for evaluating trends in sample relative abundance, Cochran's test of linear trend, results in lower rates of both Type I and Type II errors than is the case with previously used correlation-based methods.  相似文献   

2.
The majority of ancient DNA studies on human specimens have utilised teeth and bone as a source of genetic material. In this study the levels of endogenous contamination (i.e. present within the sample prior to sampling for the DNA analysis) are assessed within human bone and teeth specimens sampled from the cemetery of Santa Lucia alle Malve, Matera, Italy. This site is of exceptional interest, because the samples have been assayed for 18 measures of biochemical and physical preservation, and it is the only one identified in a study of more than 107 animal and 154 human bones from 43 sites across Europe, where a significant number of human bones was well preserved. The findings demonstrate several important issues: (a) although teeth are more resilient to contamination than bone, both are readily contaminated (presumably through handling or washing), and (b) once contaminated in this way, both are difficult (if not impossible) to decontaminate. Furthermore, although assessed on bone samples, several of the specific biochemical and physical characteristics that describe overall sample preservation, levels of microbial attack and related increases in sample porosity directly correlate with the presence of observable contamination in both bone and teeth samples from individual samples. While we can only speculate on the cause of this relationship, we posit that they provide useful guides for the assessment of whether samples are likely to be contaminated or not.  相似文献   

3.
Archaeologists have long been concerned about sample size. To monitor the relationship between sample size and the magnitude of a variable of interest, archaeologists have constructed three distinct kinds of what in ecology are known as species area curves (SACs). Sampling to redundancy SACs involve adding successive samples cumulatively to determine if the information provided by new samples is unique or redundant with information provided by earlier (smaller) samples. Rarefaction SACs involve pooling multiple samples and then rarifying the pooled sample—making it smaller probabilistically—so that the originally large but rarified sample may be compared with originally small samples. Regression SACs determine if there is a significant statistical relationship between samples of different sizes and the magnitude of the variable of interest per sample. Each of the three SACs used by archaeologists has a distinct analytical purpose.  相似文献   

4.
Detailed studies on neoplasms in prehistoric populations are rare. Each well-documented case can therefore add to our knowledge. In former times, palaeopathology could present only tentative diagnoses in the case of tumours. Today, modern diagnostic methods and a comparison with established cases make exact evaluations and their verification possible. During our study it became obvious that criteria for the diagnosis of recent tumours can be used as a guide. In this paper we present the most important findings of a malignant primary bone tumour (multiple myeloma) in an early medieval skeleton and its differential diagnoses. Even in the absence of histological findings, the remaining criteria (X-ray, age, localization, macroscopic features) permit the diagnosis of multiple myeloma to be made with some certainty.  相似文献   

5.
This study examines possible morphological variation in the knee joint of Homo sapiens with increasing age in ostensively healthy and non‐pathological distal femora and proximal tibiae. Throughout the lifetime of each individual, the hard tissue of the knee undergoes considerable remodelling as a response to biomechanical stresses, changes in bone microarchitecture and reduction of bone mineral content as a concomitant of ageing. The knee is also subject to greater levels of degenerative joint disease than any other joint. If death occurs whilst such diseases are in the earliest stages, initial bone changes may not be visually obvious in museum specimens. If such specimens are used for comparative analyses, it is hypothesised that changes might render it problematic if all ages are conglomerated into discrete samples. This study therefore investigates the degree to which the distal femur and proximal tibia change shape during ageing and, if changes are present, whether they are expressed similarly in males and females. It also examines whether changes are of greater magnitude than those morphological differences which might exist between populations. In an example population of African‐Americans, results indicate that there is a statistically significant difference in shape between age groups and those differences become progressively greater between the youngest and oldest adults. Results also show that although morphological variation caused by ageing is apparent, those shape differences attributable to sexual dimorphism are more powerful. When two additional populations are analysed jointly with the African‐Americans (Caucasian Americans and the European Spitalfields sample), results indicate that inter‐population shape differences are considerably greater than differences caused by increasing age. Results imply that it is justifiable to combine specimens of all ages into discrete samples for comparative purposes. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

6.
Abstract

During 1993 excavations at Carrick Castle, Argyll, a rare item of distilling equipment was unearthed. Possibly dating to the 17th century, the copper alloy condenser or ‘worm’ is unique in design. Pollen analysis of an associated soil sample supports a use in the production of grain spirits. The technology of manufacture and historical context of the worm are examined in depth.  相似文献   

7.
The source of the bluestones at Stonehenge has long been debated, and while there is general consensus that the so-called spotted dolerites are derived from a relatively small number of outcrops exposed in the highest parts of Mynydd Preseli, in southwest Wales the source of the rhyolitic component has attracted relatively little detailed attention. This is largely because unlike the uniqueness of the spots in the coarser grained doleritic rocks, the rhyolites are fine-grained in character and lack any obvious distinctiveness, especially in hand specimen. This makes their provenancing difficult. A recent study, however, suggested that there was a close lithological similarity between the informally-termed ‘rhyolite with fabric’ bluestone component and rhyolitic rocks from the Ordovician Fishguard Volcanic Group exposed in the Pont Saeson area of north Pembrokeshire. This study aims to see if the chemistry of zircons, which are present in both sets of samples, could be used to support the petrographical association. Analyses for certain high field strength elements (including the rare earth elements) obtained by LA-ICP-MS showed that indeed the analyses were nearly identical when compared using a range of statistical approaches, including similarity coefficients, statistical distance, and principal component analysis, while showing clear differences to sample sets which had no reason to be correlated with the Pont Saeson samples. There are two important conclusions arising from this study. Firstly, the identification of the Pont Saeson source of the ‘rhyolite with fabric’ bluestone from outcrops in low ground to the north of the Mynydd Preseli will without doubt lead to fresh debates about the mechanisms of transport of this component of the bluestones to the Stonehenge site. Secondly, the chemistry of zircons may well prove to have a wider application in the provenancing of fine-grained rhyolitic rocks which have an archaeological context.  相似文献   

8.
A. M. STOUT  A. HURST 《Archaeometry》1985,27(2):225-230
X-ray diffraction has been used to analyse the surfaces and cores of sherds from pottery from Voss and Etne. two late Roman-early Migration Period sites in western Norway. Results show: (1) the presence of illite and illite/smectite in black-burnished ware from inhumation graves which suggests that this ware was never subjected to temperatures as high as 375°C, (2) the absence of these heat-sensitive clay minerals in red ware from cremation graves at these sites which suggests a secondary firing at 700–800°C, (3) the clay minerals are similar in the cores and surfaces of the black pottery which suggests that the colour differences are due to firing procedures rather than the application of a slip, and (4) chlorite is present in all of the samples which is an indication that the ware originated in a Voss workshop where chlorite is present in other pottery found there and in the local geologic deposits.  相似文献   

9.
Aegyptiaca-like Domitian’s obelisk is now decorating Bernini’s fountain on Piazza Navona or the Egyptian lions flanking Michelangelo’s stairs towards the Capitol figure prominently amidst Rome’s cultural heritage. Motivations for the import, contextualization, and copying of these objects during the Imperial Roman period are as heavily debated as they are ill understood. Provenance determination plays an important role in these discussions in terms of a (supposed) dichotomy between Egyptian (real) versus egyptianising (copy) but has only been applied stylistically and never been tested analytically. A scientific characterization of the materials themselves is even lacking altogether, as is an investigation into the cultural and symbolic meaning of the materials used. This paper is a first attempt to address these important lacunae on the basis of an explorative study of a selected sample of Egyptian statues from Rome. The identification and provenance attribution of the materials used for these statues are often problematic due to their relatively fine-grained nature and dark color. Therefore, a full non-destructive analysis of Egyptian statues in dark-colored rocks is presented in this study, with the stones evaluated by macroscopic examination and handheld X-ray fluorescence (XRF) analysis. The implemented methodology has allowed a distinction between greywacke and several varieties of granitoid rocks. In order to evaluate the potential for source attribution, a comparison was made between the results of our analyses and geochemical data for several granitoid rocks from Egypt. This has suggested Aswan as most likely source. The results presented here indicate that handheld XRF analysis can be used for the assessment of compositional variability in and potentially for the provenance of granitoid rocks, provided that a fine-grained area of the material can be measured on multiple locations, and if these values can be assessed on (in)consistencies with other published reference materials.  相似文献   

10.
In this paper we present a new methodology for developing sample-specific metric sex determination methods using unidentified individuals that can be applied to archaeological samples. This methodology does not require the assessment of sex of a large sample from pelvic morphological features as a first step in developing the method and instead is developed from a sample of individuals with sex unknown. The procedure involves using the overall mean of a measurement collected from the sample of unknowns as the discriminant criteria for determining the sex of the individuals in that same sample. Experiments with various sample sizes and sex ratios using distal humerus measurements from the Coimbra Collection (Portugal) suggest that allocation accuracies of 83–96% can be expected when the sample used to develop the method is greater than 40 individuals and the sex ratio is less than 1.5:1. The utility of the methodology is explored using the Lisbon Collection (Portugal) and an archaeological sample from Belleville (Canada) is tested as an example. The Lisbon Collection data indicate that joint measurements of long bones will provide the highest allocation accuracies. The results from the Belleville sample confirm that humerus joint measurements consistently provide the highest allocation accuracies (88–100%) even when the sex ratio in the sample used to develop the method is estimated at 1.9:1.  相似文献   

11.
采用热释光前剂量饱和指数法对海南省中和镇的8件古城门墙砖样品进行了年代测定研究。由于该地区离海近,粘土中的含沙量非常高,古人在烧制砖时,采用这种粘土作为制砖的原料。烧造时的温度相对高于其它地方烧制的砖。其中4件砖样内部呈灰色,3件砖样内部呈红色,其中1件砖样断面为外围灰色,内部红色。在应用高温细颗粒方法测定这批砖样的年代时,发现样品的高温热释光灵敏度非常差,且不规则,没有"坪曲线",因而无法得出这些古代城门墙砖的具体年代。后采用热释光前剂量饱和指数方法对古砖样品进行了古剂量测定,发现这些样品具有较好的热释光前剂量效应,且样品的热释光灵敏度较高,得到的古剂量具有很好的重复性。热释光测年结果表明,No.2、No.3、No.6、No.8样品的热释光年代分别为:距今590年、575年、530年和580年,为明代早期烧制;No.1、No.4、No.7样品的热释光年代分别为:距今410年、345年和375年,为明代中晚期烧制;No.5样品的年代为距今140年,为清代晚期。经考古人员现场考证,认为No.5样品所处位置存在火烧痕迹。这个火烧时间应该在中国清代晚期,即热释光测定年代。  相似文献   

12.
工业旅游项目策划研究——以山西丹朱岭旅游景区为例   总被引:1,自引:0,他引:1  
工业旅游作为一个新兴的旅游项目,是近年来各工业企业开发的热点。本文首先对国内外工业旅游研究情况及旅游项目策划研究情况进行了探讨,其次以山西丹朱岭旅游景区为例,分析了工业旅游开发的可行性、工业旅游项目产品策划、营销策划,在此基础上提出了一个工业旅游项目策划模式。  相似文献   

13.
Injuries classified as parry fractures, normally the result of a direct blow when the forearm is raised to shield the face, are significant in bioarcheological interpretations because the parry fracture is perceived as an indicator of interpersonal (or extramural) violence. It is therefore necessary that these injuries be correctly identified in order to properly interpret the trauma pattern and its social implications for abuse, gender and power relations among ancient people. Common acute forearm fractures are reviewed here and quantitative guidelines that define the parry fracture configuration are presented. The parry criteria include: (1) an absence of radial involvement, (2) a transverse fracture line, (3) a location below the midshaft (<0.5 adjusted distance to the lesion's center), and (4) either minor unalignment (<10°) in any plane or horizontal apposition from the diaphysis (<50%). A sample of 278 adults from northern Sudan dated to the Nubian Bronze Age (ca. 2500–1500 BC) contained 38 individuals with forearm fractures. Of these fractures, 21 out of the 28 ulna injuries were identified as parry fractures using the parry criteria. Fewer females suffered from parry fractures than when ulna injuries were identified by location on the ulna alone. The use of the parry criteria may not always affect the results significantly, but here interpersonal violence directed against women and amongst ancient Nubians was found to be less prevalent than implied in earlier studies. The absence of perimortem parry fractures suggests that the Kermans interred within mass burials were not physically forced to their graves. Chronic ulna stress fractures associated with sports and habitual activities must also be considered as a differential diagnosis of this injury.  相似文献   

14.
Mexican prehistory is characterized by migration and population isolation in its earliest phase, followed by later inter‐population cultural interactions, such as politics and trade. While shared, common morphological variants are often informative about recent population events, rare trait variants have not been widely investigated to see whether they might be informative about earlier events. Here, we consider populations that show several rare variants at frequencies high enough to warrant such an investigation. Examining past population structure can help us understand population interactions across different periods of time, levels of migration, and population isolation/drift. Multiple‐origin populations may have more variation, including more and higher rates of rare traits. We examined maxillary lateral incisors in 1117 dentitions from 76 samples of Preclassic/Classic and Postclassic pre‐European contact Mexico and the American Southwest for the prevalence of rare lateral incisor variants. Variants observed included barrel, congenital absence, interruption groove, mesial marginal bending, peg, reduced, supernumerary, and talon teeth. The most common variant overall is interruption groove. Central Mexico, Huasteca, and the Lowland Yucatan region samples present the highest overall number of incisor variants. Higher frequencies of single unusual traits are commonly found in samples from smaller populations, while samples from larger population centres show a greater range of these rare variants. We investigated to see whether the pattern of rare incisor variant frequencies reflected early or later population history by comparing similarity/distance matrices and factor model matrices using Mantel tests and Generalized Procrustes analysis. Results show a weak relationship with the Postclassic period and shared migration/language and trade interaction models. We suggest that later cultural interactions have acted to mask earlier population history. Research on serial founder effects should be approached multiregionally and across time, to avoid missing inter‐region biological relationships. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

15.
Abstract

Cultural resource management the world over confronts the perpetual dilemma of deciding which part of the past to preserve for whose future. This dilemma arises from the perpetual tension between the insistent drive to develop for the future and the presumptive need to preserve the past. In the face of constraints imposed by limitations of time, money and personnel, advocates of preservation face difficult choices of which sites to rescue and which to abandon to destruction. There are also other aspects of the dilemma: choosing the criteria on which preservation decisions are to be based; determining who in the end will apply these criteria; and deciding on whose behalf the chosen sites will be preserved and maintained. The dilemma resolves itself into three questions: ‘Which sites?’, ‘What public?’ and ‘Who decides?’. The answers are found, at least provisionally, in an examination of case studies, from Tunisia, Cyprus and Jordan, that typify the dilemma and illustrate the various strategies, successful and otherwise, deployed to confront it.  相似文献   

16.
Matthew B. Anderson 《对极》2019,51(4):1035-1056
This study examines the role of class monopoly rent in shaping the spatial form and pattern of urban redevelopment processes in the contemporary neoliberal city. Since an initial flourishing literature during the 1970s and 1980s, urban land rent theory has fallen from the analytic radar of critical urban studies since the early 1990s, with the influence of class monopoly rent often considered an aberration of how capitalist real estate markets normally operate, if not rejected. Consequently, class monopoly rent has never been systematically elaborated. Based on an empirical analysis of Portland's Pearl District, this study suggests that the influence of class monopoly rent in contemporary processes of urban redevelopment is far more pervasive than often recognised, representing a “standard institutional practice” that is endemic (rather than aberrational) to the working of neoliberal urban governing regimes, and embeds in the social and physical landscape in a multiplicity of ways.  相似文献   

17.
Palaeozoological data are asymmetrical because they indicate the presence of a species in the area in which its remains are recovered, but the absence of remains is not necessarily evidence for the absence of a species. It is impossible to measure the magnitude of data asymmetry with respect to biogeography, but the magnitude can be estimated. The proportion of sites in an area where a species is known to occur that have not produced remains of that species is an estimate of counter‐ubiquity. The proportion of identified faunal remains in an area where a species is known to occur that do not represent that species is another estimate of data asymmetry. Bivariate plots of the number of sites in an area that have produced remains of a taxon against the total number of faunal remains identified in the area indicate that data asymmetry can be estimated as the inverse of sample size. More sites and more identified faunal remains tend to produce more occurrences of a species, so more sites and more identified faunal remains will tend to provide a database that is not only more accurate but also less asymmetrical with respect to the geographical range of a species. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

18.
Polymerase chain reaction (PCR) inhibitors are often co-extracted with ancient DNA (aDNA) and when present make the analysis of aDNA difficult, if not impossible. In this study we review previous research on PCR inhibitors and techniques that address their co-extraction with DNA from sub-optimal samples. Additionally, we introduce a simple extraction technique, “repeat silica extraction,” that effectively removed PCR inhibitors from extracts of 7000–8000-year-old human skeletal remains from the Windover archaeological site in Florida and 700–2000-year-old human coprolites excavated from Fish Slough Cave in southern California. A series of tests on these same samples demonstrates that N-phenacylthiazolium bromide is largely ineffective, despite previously reported success using this compound as part of the DNA extraction process. We also describe a method for demonstrating the presence as well as successful removal of PCR inhibitors by use of a “positive aDNA control,” a test necessary to conclude that negative PCR amplification is the result of the absence of preserved DNA.  相似文献   

19.
In this paper, three approaches for developing sample-specific sex determination methods of immature skeletal remains based on permanent tooth dimensions are proposed and tested using a sample of identified skeletons. The sample comprises adult and subadult individuals selected from the Lisbon documented skeletal collection, housed at the National Museum of Natural History in Lisbon, Portugal. Faciolingual and mesiodistal diameters were the tooth dimensions utilized. In the first approach, sex-specific logistic regression formulae based on adult tooth dimensions are developed and then used to determine the sex of the subadult sample. The second and third approaches are based on the sectioning point procedure, which uses the overall mean of a measurement (tooth diameter) collected from the sample as the discriminant criteria for determining the sex of the individuals in that sample. While in the second approach the adult overall mean of each dimension is used as the discriminant criteria for determining the sex of the subadults, in the third approach it is the subadult overall mean of each dimension that comprises the discriminant criteria that is applied back to the subadults for determining sex. Results show that the canines are the teeth with the highest sexual dimorphism and methods of sex determination based on canine dimensions provide correct allocation accuracies between 58.8% and 100% depending on the diameter and the approach that is being used. Canine faciolingual dimensions provide the best overall results. Combinations of measurements from the same and different teeth do not increase significantly the accuracy of the methods and approaches. Some of the problems of subadult sex determination methods based on adult tooth dimensions result from differing levels of sexual dimorphism between the adult and subadult segment of the sample. Mortality or cultural bias may increase or decrease the sexual dimorphism of the subadults compared to the adults. Small subadult samples utilized in this study may also raise questions regarding the accuracy of the three different sample-specific approaches. However, high consistency of results using the canine and different approaches, suggests that adult and subadult canine dimensions can be reliable sex discriminators of immature skeletal remains in archaeological samples. The major advantage of the approaches presented here is that they can be used to derive sample-specific methods and, therefore, eliminate the problem of applying morphological or metric methods to individuals originating from a population that differs from the one that contributed to the development of the method.  相似文献   

20.
Criteria developed to distinguish between selected postcranial elements of sheep and goats are evaluated using modern specimens from the collections of the Field Museum of Natural History, the National Museum of Natural History, and the Museum of Anthropology and the Museum of Zoology, University of Michigan. Elements considered are: the distal humerus, proximal and distal radius, distal tibia, distal metapodials, astragalus, calcaneus, and the first and second phalanx. This evaluation includes an assessment of 1385 elements from 49 goat and 84 modern sheep skeletons. It also includes a blind test on elements drawn from 20 specimens taken by six analysts with differing levels of experience. Overall, the criteria evaluated are highly reliable, especially in goats and only slightly less so in sheep. A major exception is the distal tibia, where diagnostic criteria tested proved substantially less reliable than other criteria evaluated here. Strongly positive results were also obtained when the sample was partitioned by sex, domestic status, and age. Results of the blind test show some variability depending on the level of experience of the analyst, underscoring the need for training and access to adequate modern reference collections before attempting to apply these criteria to archaeological assemblages. The results of this assessment stand in stark contrast to those obtained in an earlier assessment of the reliability of criteria used to distinguish between mandibles and mandibular teeth of sheep and goats. In all but a few teeth, dental criteria proved to be much less reliable, especially in goats. They were also significantly less reliable in the identification of both younger and older animals. Unlike dental criteria, there are no biases introduced by variable reliability of postcranial criteria that distort taxon-specific harvest profiles based on long-bones.  相似文献   

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