Effect of mollusc eating on human bone strontium levels

Empirical aspects of the movement of strontium through the food chain suggest that the level of bone strontium can be used as an indicator of the percentage of meat in human diet. In general, skeletal remains from agricultural peoples are expected to have high bone strontium levels relative to hunter-gatherers from the same geographical region because plants contain relatively higher amounts of strontium when compared with animal products. The results of the study described in this paper, however, indicate that the inclusion of molluscs as a component of the diet may produce the opposite of the expected strontium values. Burials from an Archaic (c. 2500 BC) hunting-gathering population excavated from Lu^o25, an archaeological site in northern Alabama, USA, exhibit a mean bone strontium level ( atomic absorption; neutron activation) that is higher than the mean level from an agricultural Mississippian (c. AD 1400) population ( atomic absorption; neutron activation) that was buried at the same site. The samples were analysed by two techniques (atomic absorption spectrometry and neutron activation analysis) and the results compared favourably; therefore, the results can be accepted as valid rather than being due to technique error. We propose that the ingestion of molluscs, whose meat is known to contain large amounts of strontium, has produced this reversal from expected results.     

Collagen deamidation in archaeological bone as an assessment for relative decay rates

Attempts to extend methods for dating archaeological bones beyond that of radiocarbon dating, such as amino acid racemization, have met with limited success owing to the dependence on multiple environmental factors and controls. Despite facing similar challenges, deamidation of glutamine has recently been investigated as a potential indicator of ‘thermal age' in archaeological bones, as well as a measure of their preservation quality. In this study, we undertook a series of simulated diagenetic experiments to understand the various factors affecting deamidation. Further, we analysed bones from different Middle Palaeolithic layers from Grotte Mandrin (France), with the results suggesting potential use of deamidation for relative dating, but only in case of extremely well‐preserved layers. The results also suggested the possible use of attenuated total reflectance‐Fourier transform infrared (ATR‐FTIR) spectroscopy as a screening test for soluble collagen before proteomic analysis.     

Bone diagenesis in the European Holocene II: taphonomic and environmental considerations

We have applied cluster analysis to mercury intrusion porosimetry data from 219 archaeological bones (121 human and 98 animal) and soil chemistry data from 219 accompanying soil samples (1 per bone sample), to investigate the influence of soil chemistry on bone preservation. The samples chosen for the study were obtained from sites ranging in time from the pre-modern to the Mesolithic and were representative of burial environments across Europe (from the Baltic to the Mediterranean). These results represent the single largest database for archaeological bone preservation in the European Holocene to date and demonstrate the potential for large-scale diagenetic studies to help develop long term preservation strategies for our European heritage. Despite the variety of sites and environments, bones could be categorised into only four main diagenetic types. Furthermore, soil chemistry appears to significantly affect only one type of preservation, the pathway characterised by loss of mineral. In neutral to basic soils, taphonomy and in particular the differences between the treatment of human and animal remains, becomes the dominating factor in determining preservation. Using these results, strategies for heritage management of archaeological sites can be suggested; grouping sites into those requiring immediate excavation and those where in situ preservation is viable.     

Sources of variation in carnivore tooth-mark frequencies in a modern spotted hyena (Crocuta crocuta) den assemblage,Amboseli Park,Kenya

Distributions and frequencies of carnivore tooth-marks on large mammal long-bone fragments are commonly used to infer the timing of hominin and carnivore access to prey resources in archaeofaunal assemblages. The strength of these inferences, however, is limited by a broad and currently inexplicable range of tooth-mark frequencies across experimental and archaeological assemblages. Controlling for this variation first requires that the sources be identified. Several sources of variation are examined here in an analysis of tooth-marked bone recovered from a modern spotted hyena (Crocuta crocuta) den assemblage in Amboseli Park, Kenya. Results indicate that tooth-mark frequencies: (1) depend on fragment size, (2) vary across mammals of different size classes, (3) are highly variable across equivalent portions of different long-bone elements, and (4) on certain long-bone portions are correlated with bone density and can be depressed in archaeological assemblages subjected to density-mediated attrition. Stronger inferences based on tooth-mark frequencies will require that such variation be taken into consideration, and methods for doing so are suggested.     

Are Teeth Better? Histological Characterization of Diagenesis in Archaeological Bone–Tooth Pairs and a Discussion of the Consequences for Archaeometric Sample Selection and Analyses

Teeth are often the preferred source material for isotopic and genetic assay involving ancient biomolecules. The assumption is that dental tissue preserves better due to its anatomically protected location, the enamel cap, and lower porosity compared to bone. However, this assumption has not been widely tested. Some similarities in diagenetic processes are to be expected due to similarities in structure and chemical composition of dentine and bone. This has led to the suggestion that bone can be used as an indicator of dental preservation, as a pre‐screening technique in the selection of suitable samples for biomolecular studies. Thus, direct testing of the correlation between bone and tooth preservation and diagenesis is needed. This paper reports the results of the histological characterization of diagenetic alterations within 25 human femur–tooth pairs, from a Medieval to modern (AD 1850) cemetery in Eindhoven, the Netherlands. The results showed that teeth do indeed preserve better overall, but not always, and that this was dependent on the main diagenetic factor(s) at the burial location. Furthermore, good correlations are found between the microstructural preservation of bone and teeth; similar processes of decay were observed within bone and teeth of the same individual. Overall, the study demonstrated that histological analysis of bone is useful for the identification of degradation processes that affect biomolecular preservation in skeletal material. In this way, sample selection and analytical strategies can be optimized. Copyright © 2013 John Wiley & Sons, Ltd.     

Stable Isotope Analysis of Human and Animal Remains at the Qijiaping Site in Middle Gansu,China

Intercontinental exchanges between communities living in different parts of Eurasia during the late prehistoric period have become increasingly popular as a topic of archaeological research. The Qijia culture, found in northwest China, is one of the key archaeological cultures that can shed light on trans‐Eurasian exchange because a variety of imports are found in this cultural context. These imports include new cereals and animals, which suggest that human diets may also have changed compared with previous periods. To understand human and animal diets of the Qijia culture, carbon and nitrogen isotope ratios from human and animal skeletal remains were analysed from the type site of the Qijia culture at Qijiaping. The results demonstrate that human diet at the site mainly consisted of millet and animals fed on millet. C₃ cereals, such as wheat and barley, did not contribute significantly to human diet, and no isotopic differences were found between adult and subadult diets. Furthermore, three outlying human results raise the possibility of exogenous individuals, perhaps in relation to the parallel movement of animals, crops and goods. This study provides human and animal dietary information for evaluating the nature of exchange and diffusion in eastern Eurasia at this time. Copyright © 2013 John Wiley & Sons, Ltd.     

Multi-element analysis for dietary reconstruction at a balearic Iron Age site

The number of studies using trace elements as indicators of diet has increased with time, but the majority have used few elements and a small sample. The present study has as a principal objective a multi-element analysis of diet in a large sample in which diagenetic changes have been shown to be unimportant. The analysis was made using concentrations of seven elements—Sr, Ba, Mg, Cu, Zn, V and Ca—in 197 individuals from the necropolis of ‘S' Illot des Porros’ (Majorca, Spain). The results show that these individuals would have had a mixed diet with a high meat component, principally of marine origin (molluscs and fish), but with an important consumption of seeds and cereals and a low proportion of vegetables.     

Effects of Sodium Hydroxide Treatment and Ultrafiltration on the Removal of Humic Contaminants from Archaeological Bone

This study compared bone collagen extraction techniques that included treatment with sodium hydroxide and 30 kDa ultrafilters using a set of well‐preserved, humic‐contaminated archaeological marine mammal bones. Treatment with sodium hydroxide was effective at removing humic contaminants from archaeological bone, although yields were significantly decreased. Yields were also significantly decreased by ultrafiltration although this study produced no evidence that 30 kDa ultrafilters were effective at selectively removing humic contaminants from archaeological bone. The combination of sodium hydroxide treatment and ultrafiltration did not produce superior results to the treatment involving only sodium hydroxide. Archaeological samples exhibiting darker colouration indicative of humic contamination should be treated with sodium hydroxide to remove these contaminants. Copyright © 2017 John Wiley & Sons, Ltd.     

On the Origin of the Green Colour of Archaeological Bone Artefacts of the Gallo‐Roman Period

Recent findings in the city of Reims have lead to the discovery of manufactured bone objects coloured in green throughout their entire volume. In order to discover the intentional nature of the colouration and to propose a colouration mechanism, modern ox bones have been coloured in the laboratory. Bones with a hue similar to that of the archaeological artefacts have been obtained by boiling in an acidic brine in a copper vessel. A combination of infrared spectroscopy, X‐ray diffraction and transmission electron microscope observations did not reveal the speciation of copper, but allowed us to validate the colouration process and to discuss the intentional origin of the colouration.     

Bone preservation in human remains from the Terme del Sarno at Pompeii using light microscopy and scanning electron microscopy

Archaeological bone can show marked and complex alterations depending on the environment in which it was buried. In this study, the state of preservation of 27 femurs recovered from the archaeological site of Pompeii was evaluated by light microscopy and scanning electron microscopy. Most of the bone samples, prepared by the grinding method, showed good histological preservation, although they were characterized by microfissures (microcracking). Nine bone samples showed different states of histological preservation, including worst preservation (two femurs), due to diagenetic processes. Cryostat bone sections stained with thionin or 4′,6′-diamidino-phenylindole (DAPI) revealed the persistence of DNA within some osteocyte lacunae. Scanning electron microscopy analysis showed that ultrastructural characters, such as lamellae and collagen fibres, are recognizable only in unaltered bone. Our results reveal that most Pompeian samples are well preserved since they have a bone microstructure virtually indistinguishable from that of fresh bone. In methodological terms, although each of the various morphological methods used contributes information, histological and histochemical analyses are the most informative for studying the preservation state of bone and allow for rapid essential screening of archaeological bone.