This review charts the developments and progress made in the application of stable light isotope tools to palaeodietary adaptations from the 1970s onwards. It begins with an outline of the main principles governing the distribution of stable light isotopes in foodwebs and the quality control issues specific to the calcified tissues used in these analyses, and then proceeds to describe the historical landmark studies that have marked major progress, either in their archaeological applications or in enhancing our understanding of the tools. They include the adoption of maize agriculture, marine-focused diets amongst coastal hunter-gatherers, trophic level amongst Glacial-period modern humans and Neanderthals, and the use of savannah resources by early hominins in Africa. Particular attention is given to the progress made in addressing the challenges that have arisen out of these studies, including issues related to the routing of dietary nutrients. I conclude with some firm, and some more speculative, pointers about where the field may be heading in the next decade or so.
The recording and 3D modelling of complex archaeological sites is usually associated with high capital and logistical costs, because the data acquisition must be performed by specialists using expensive surveying sensors (i.e., terrestrial laser scanners, robotic total stations and/or ground‐penetrating radar). This paper presents a novel, low‐cost, user‐friendly photogrammetric tool for generating high‐resolution and scaled 3D models of complex sites. The results obtained with unmanned aerial vehicle (UAV) photogrammetry of an archaeological site indicate that this approach is semi‐automatic, inexpensive and effective, and that it guarantees quality.
Incremental dentine analysis utilizes tissue that does not remodel and that permits comparison, at the same age, of those who survived infancy with those who did not at high temporal resolution. Here, we present a pilot study of teeth from a 19th‐century cemetery in London, comparing the merits of two methods of obtaining dentine increments for subsequent isotope determination. Covariation in δ13C and δ15N values suggests that even small variations have a physiological basis. We show that high‐resolution intra‐dentine isotope profiles can pinpoint short‐duration events such as dietary change or nutritional deprivation in the juvenile years of life.
Organic residue analysis utilizes analytical organic chemical techniques to identify the nature and origins of organic remains that cannot be characterized using traditional techniques of archaeological investigation (because they are either amorphous or invisible). The field is founded upon the principle that the biomolecular, or biochemical, components of organic materials associated with human activity survive in a wide variety of locations and deposits at archaeological sites. The archaeological information contained in organic residues is represented by the biomolecular components of the natural products that contribute to the formation of a given residue. By applying appropriate separation (chromatographic) and identification (mass spectrometric) techniques, the preserved, and altered, biomolecular components of such residues can be revealed. Once identified, the Archaeological Biomarker Concept can be applied, wherein the structure and even isotopic composition(s) of a given biomolecule or suite of biomolecules (the `chemical fingerprint') can be related to the compositions of organisms exploited by humans in the past. As the organic residue field emerges from its pre-paradigmatic phase, and the organic residue revolution gathers pace, the way is open for challenging many long-held archaeological hypotheses and offering new perspectives on the study of human activity in the past.
Maya blue is an organo-clay artificial pigment composed of indigo and palygorskite. It was invented and frequently used in Mesoamerica in ancient times (eighth to 16th centuries). We analyse in this paper one of the characteristics of Maya blue that has attracted the attention of scientists since its rediscovery in 1931: its high stability against chemical aggression (acids, alkalis, solvents, etc.) and biodegradation, which has permitted the survival of many works of art for centuries in hostile environments, such as the tropical forest. We have reproduced the different methods proposed to produce a synthetic pigment with the characteristics of the ancient Maya blue. The stability of the pigments produced using either palygorskite or sepiolite has been analysed by performing acid attacks of different intensities. The results are analysed in terms of pigment decolouration and destruction of the clay lattice, revealed by X-ray diffraction. Palygorskite pigments are much more resistant than sepiolite pigments. It is shown that indigo does not protect the clay lattice against acid aggression. We show that Maya blue is an extremely resistant pigment, but it can be destroyed using very intense acid treatment under reflux.
Since the 1980s, several experimental analyses have been able to differentiate some lithic tool types and some of their raw materials according to the morphology of cut marks imprinted by such tools when used for butchering activities. Thus, metal tool use has been differentiated in contexts with an abundance of lithic tools, or even the use of hand axes has been documented in carcass processing, in contrast with simple unretouched or retouched flakes. As important as this information is, there are still other important aspects to be analysed. Can cut marks produced with different lithic raw material types be differentiated? Can cut marks made with different types of the same raw material type be characterized and differentiated? The objective of this study is to evaluate if cut marks resulting from the use of different flints and different quartzites are distinguishable from each other. In the present work, an experimental analysis of hundreds of cut marks produced by five types of flint and five varieties of quartzite was carried out. Microphotogrammetry and geometric–morphometric techniques were applied to analyse these cut marks. The results show that flint cut marks and quartzite cut marks can be characterized at the assemblage level. Different types of flint produced cut marks that were not significantly different from each other. Cut marks made with Olduvai Gorge quartzite were significantly different from those produced with a set comprising several other types of quartzites. Crystal size, which is larger in Olduvai Gorge quartzites (0.5 mm) than Spanish quartzites (177–250 μm), is discussed as being the main reason for these statistically significant differences. This documented intra‐sample and inter‐sample variance does not hinder the resolution of the approach to differentiate between these two generic raw material types and opens the door for the application of this method in archaeological contexts.
One hundred and ninety three glass fragments from the canabae in York were analysed (first to fourth centuries). They fall into six compositional groups: antimony colourless (Sb), high‐manganese (high‐Mn), low‐manganese (low‐Mn), mixed antimony and manganese (Sb–Mn), high iron, manganese and titanium (HIMT) and plant ash. Some groups represent production groups, some of which appear to be in limited supply in this western outpost, but are more prevalent elsewhere, and others reflect changing supply mechanisms. The majority of glasses fall into groups that demonstrate extensive recycling of glass. This has important implications for determining provenance using trace elements and isotopes.
The contribution of the physical sciences to the reconstruction of the production technology (i.e., processing of raw materials, forming, surface treatments and firing methods) for earthenwares, stonewares, porcelains and stonepaste bodies are summarized. The organization of production and the reasons for technological choice are considered. Provenance studies based on both chemical analysis and thin‐section petrography are discussed, with the investigation of Minoan and Mycenaean pottery being taken as the case study. The approaches to determining how pottery vessels were used in antiquity are outlined. Finally, future developments in ceramic studies are briefly considered.
Quantitative individual human diet reconstruction using isotopic data and a Bayesian approach typically requires the inclusion of several model parameters, such as individual isotopic data, isotopic and macronutrient composition of food groups, diet‐to‐tissue isotopic offsets and dietary routing. In an archaeological context, sparse data may hamper a widespread application of such models. However, simpler models may be proposed to address specific archaeological questions. As a consequence of the intake of marine foods, individuals from the first century ad Roman site of Herculaneum showed well‐defined bone collagen radiocarbon age offsets from the expected terrestrial value. Taking as reference these radiocarbon offsets and using as model input stable isotope data (δ13C and δ15N), the performance of two Bayesian mixing model instances (routed and concentration‐dependent model versus non‐routed and concentration‐independent) was compared to predict the carbon contribution of marine foods to bone collagen. Predictions generated by both models were in good agreement with observed values. The model with higher complexity showed only a slightly better performance in terms of accuracy and precision. This demonstrates that under similar circumstances, a simple Bayesian approach can be applied to quantify the carbon contribution of marine foods to human bone collagen.
Simple flake cutting tools were utilized across broad chronological and geographical ranges during prehistory. Fundamental to their functional utility is the presence of a relatively acute working edge. The acuteness of this ‘edge angle’ is widely hypothesized to be a primary determinant of cutting efficiency and, subsequently, of potential consequence to prehistoric peoples. However, the influence of the cutting edge angle in flake tools on the ability (efficiency) of tool users to cut through objects has not been empirically investigated under explicitly stated experimental conditions. Moreover, no consideration has been given to whether this relationship is dependent upon the size of the tool. Here, the influence that edge angle exerts on human stone tool users is examined experimentally in terms of efficiency during a cutting task, while also considering the relationship between edge angle, loading (i.e., the force applied) and overall flake size. The results demonstrate that there is a highly significant relationship between more acute working edges and increased cutting efficiency in the smallest flake tools tested. Above a certain flake‐size threshold, however, the working edge angle has no influence on cutting efficiency because larger flakes appear to facilitate the application of greater working loads by tool users. These results have important implications for potential flake selection criteria by prehistoric peoples, especially in relation to utility, function and the changing effects of edge angle through a sequence of retouch.
Radiocarbon dating has undergone a number of `revolutions' in the past 50 years. This is in part because it is a field in continuous development, but perhaps more because of its profound impact on archaeology and the nature of interdisciplinary research. In order to understand the use of radiocarbon as a dating tool, it is necessary to understand the life cycle of radiocarbon, from its production in the upper atmosphere, through its sequestration in reservoirs and samples and its final decay. Different elements in this life cycle lead to complications, or subtleties that need to be understood if we wish to develop high-resolution chronologies. Most of the changes that have influenced radiocarbon dating are revolutions in understanding of the natural world in disparate academic disciplines. More than ever, it is necessary for users of radiocarbon to understand and engage with the science that underlies the method.
We evaluate local versus distant land‐use models at Neolithic Çatalhöyük, central Anatolia, using strontium isotope analysis of sheep tooth enamel and charred plant remains. Interpretation of strontium in sheep tooth sequences is constrained by previous oxygen isotope work, which largely excludes summer movement to the mountains but cannot distinguish between herding on the plain and the closest upland‐zone, Neogene limestone terraces. We establish a baseline contrast in modern plant strontium values between the plain and terraces and infer predominant herding on the plain from seven sheep tooth sequences. Archaeobotanical plant strontium values exclude the use of the terraces for cultivation and foraging. Relatively local crop and sheep management, plausibly intensive and integrated to some degree, given limited dry ground, appears likely on the basis of this pilot study.
The most crucial parameter to be determined in an archaeological ground‐penetrating radar (GPR) survey is the velocity of the subsurface material. Precision velocity estimates comprise the basis for depth estimation, topographic correction and migration, and can therefore be the difference between spurious interpretations and/or efficient GPR‐guided excavation with sound archaeological interpretation of the GPR results. Here, we examine the options available for determining the GPR velocity and for assessing the precision of velocity estimates from GPR data, using data collected at a small‐scale iron‐working site in Rhode Island, United States. In the case study, the initial velocity analysis of common‐offset GPR profile data, using the popular method of hyperbola fitting, produced some unexpectedly high subsurface signal velocity estimates, while analysis of common midpoint (CMP) GPR data yielded a more reasonable subsurface signal velocity estimate. Several reflection analysis procedures for CMP data, including hand and automated signal picking using cross‐correlation and semblance analysis, are used and discussed here in terms of efficiency of processing and yielded results. The case study demonstrates that CMP data may offer more accurate and precise velocity estimates than hyperbola fitting under certain field conditions, and that semblance analysis, though faster than hand‐picking or cross‐correlation, offers less precision.
We present a new method to assess use‐wear formation processes of pounding tools used to break bones based on a combination of conventional microscopy, optical 3D surface measurements obtained with a confocal microscope and GIS analysis. The method involves 3D alignment and 3D surface change inspection techniques along with a surface morphometric characterization and 2D spatial pattern analysis, to measure the spatital distribution of significant changes in surface topography of pounding tools. Our results show that microscopic changes can be detected in the surfaces of hammers and anvils after bone breakage activities are performed. Use‐wear on the active elements (hammers made on basalt and quartzite) occurred over a larger area than was observed on the passive element (quartzite anvil), but the latter often exhibited deeper modifications. Tool surfaces generally developed smoother topography with increased use, but grain microfracture also appeared with greater frequency over time. This methodology offers highly accurate and statistically robust analyses of microscopic use‐wear traces that can be applied to the analysis of archaeological pounding tools.
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.
A large analytical programme involving both obsidian source characterization and obsidian artefact sourcing was initiated recently within the framework of the French archaeological mission ‘Caucasus’. The results will be presented in two parts: the first part, this paper, deals with the presentation and characterization of obsidian outcrops in the southern Caucasus, while the second presents some results obtained from a selection of artefacts originating from different Armenian sites dated to between the Upper Palaeolithic and the Late Bronze Age. The same analytical method, LA–ICP–MS (laser ablation inductively coupled plasma mass spectrometry), has been used to characterize all the studied samples (both geological and archaeological). This method is more and more widely used to determine the elemental composition of obsidian artefacts, as it causes minimal damage to the studied objects. We present in this first part new geochemical analyses on geological obsidians originating from the southern Caucasus (Armenia, Georgia) and eastern Turkey. These data enhance our knowledge of the obsidian sources in these regions. A simple methodology, based on the use of three diagrams, is proposed to easily differentiate the deposits and to study the early exploitation of this material in the southern Caucasus.
High mobility among Scythian populations is often cited as the driving force behind pan‐regional interactions and the spread of new material culture c.700–200 bce, when burgeoning socioeconomic interactions between the Greeks, Scythian steppe pastoralists and the agro‐pastoral tribes of the forest‐steppe played out across the region. While interregional mobility central to warrior lifestyles is assumed to have been a defining feature of Scythian populations, strikingly few studies have investigated human mobility among communities located along the steppe and forest‐steppe boundary zone. Here, we document movement and dietary intake of individuals interred at Bel'sk, a large urban settlement in Ukraine, through strontium, oxygen and carbon isotope analyses of human tooth enamel. The results provide direct evidence for limited mobility among populations from Bel'sk, demonstrating the movement into, and out of, urban complexes. Strontium and oxygen isotope analyses reveal that groups at Bel'sk remained local to the urban complex. Dietary intake, reflected in carbon isotopes, was based on domesticated crops and livestock herding. The combination of low mobility alongside dietary evidence suggests local groups engaged in sedentary agro‐pastoral subsistence strategies that contrast sharply with the picture of highly mobile Scythian herders dependent on livestock portrayed in historical sources.
The question of whether rock grit ingested unintentionally from querns, metates or millstones, or deliberately through pica or geophagy, is bioaccessible in the human gut has not been addressed in archaeological strontium (Sr) isotope studies. This study employed the unified bioaccessibility method and determined that ingested rock grit can provide bioaccessible 87Sr/86Sr, but that unintentional consumption is unlikely to constitute > 1% of the diet (by mass) and will not significantly change, that is, by > 0.001, human skeletal 87Sr/86Sr. The use of locally or non‐locally sourced querns or millstones will not affect the interpretation of archaeological human 87Sr/86Sr values in Britain.
Because it is often difficult to preserve fragile relics in situ at underwater cultural heritage sites, it is sometimes necessary for relics to be extracted and moved to a controlled environment on land for protection and study. This paper discusses the feasibility of using the volatile organic compound veratraldehyde as a temporary consolidant for underwater fragile relics extraction. The results show that different materials (iron, tile, sand, wood) under water can be bonded together and extracted when using veratraldehyde. The fact that veratraldehyde is difficult to spread on the surface of underwater objects is a problem that can be solved by adding a layer of strong hydrophobic polypropylene (PP) fibres onto the object, serving as a ‘package' for the relics. Under laboratory conditions, we used veratraldehyde and PP fibres to extract broken tiles from underwater sand onto an exhibition stand. The broken tiles, in both condition and distribution, were safely and completely retained as the veratraldehyde was slowly removed by the soaking process. This work fills a gap in knowledge about temporary consolidant materials in underwater archaeology, and provides a new method for extracting underwater fragile cultural relics without damaging them.
The mensuration of multi‐elemental concentrations from assorted archaeological materials has always required great care and attention to detail to ensure good‐quality data and their ensuing interpretations. Although most suspect data were generated before the wide use of computers, error‐free data are not still a certainty. This paper presents the geochemical rationale for a proposed chemical data‐assessment process, using a globally dispersed collection of ceramic, sediment and lithic data. It is argued that this process can allow archaeologists and archaeometrists to investigate systematically older and current data sets and, if need be, alter them to the reliable values they were originally intended to include.