REVIEW ARTICLE USE-WEAR ANALYSIS: THE STATE OF THE ART

This paper is a review of the recent developments in use-wear analysis. The focus is on some key issues: polish formation, quantification of use-wear, residue analysis and the way these related themes have affected methods of use-wear analysis. A brief history of the development of use-wear analysis is presented and a discussion of blind tests, expert systems (explained at length in the ‘Appendix’) and how use-wear analysis can be incorporated into the chaîne opératoire approach to the interpretation of Stone Age sites.     

A review of “Investigating microwear polishes with blind tests”

A recent article by M. Newcomer, R. Grace & R. Unger-Hamilton published in the Journal of Archaeological Science (1986) takes a critical approach to the question of microwear polish. By means of blind tests and texture analysis by computer, the authors attempt to show that microwear polishes are not distinct from one another. The present review takes exception, not to criticism of microwear analysis, but to the faulty approach taken by Newcomer et al., which may engender a misunderstanding of functional analysis as a whole. A point-by-point critical review of Newcomer et al. indicates that their evidence is invalid and ought not to be taken as a measure of progress in microwear studies.     

Small things in perspective: the contribution of our blind tests to micro-residue studies on archaeological stone tools

Our blind tests are distinctive for they were conducted on replicated stone tools used for a variety of tasks that included the processing of animal remains and plants. The analyst was required to differentiate an array of residues from microscopic morphological characteristics, using light microscopy. The original aim of our first tests was to assess the analyst's ability to identify a variety of plant and animal residues, but issues and problems that arose during the testing process made it clear that greater value might be gained from the lessons that we learnt about methodology and the direction for future micro-residue research. We show that problems identified during our first tests stimulated research. Amongst other things, we learnt to distinguish plant and animal remains more confidently than previously. Our residue analyses are firmly embedded in wider archaeological research and our tests help to explain why there are sometimes contradictions between the evidence from archaeologically recovered remains and residues on stone tools. A further outcome of the tests is that we have adopted a multi-stranded approach that provides a cautious, but secure strategy for identifying and interpreting use-residues. Our studies of contaminants through replications have also been invaluable for distinguishing incidental residues from use-related residues.     

The use of an improved pRIA technique in the identification of protein residues

Blood and protein residue identification in archaeological research has been a controversial subject for the last 20 years. This paper reports on the use of an improved protein radioimmunoassay (pRIA) technique in identifying protein residues. Results from the blind testing of the original and improved pRIA techniques in identifying bloodstains on experimental lithic artifacts are described and compared. We argue that the improved pRIA technique is highly sensitive and accurate for identifying protein residues to genus, and thus has excellent applications for archaeological research.     

Testing the accuracy of portable X-ray fluorescence to study Aztec and Colonial obsidian supply at Xaltocan,Mexico

This article demonstrates the accuracy of non-destructive portable X-ray fluorescence (pXRF) for the study of obsidian in central Mexico. Obsidian sources were identified for a sample of 103 artifacts from the site of Xaltocan, which spanned the rise and fall of the Aztec empire and the first centuries of Spanish colonial rule (AD 900–1700). Sources were assigned by comparing pXRF measurements with previously published source data and were verified using the standard techniques of laboratory XRF (lXRF) and instrumental neutron activation analysis (INAA). Additional tests of potentially confounding factors show that neither length of read time, presence of surface residue, nor incomplete detector coverage due to small artifact size compromised our ability to attribute sources to artifacts. Concave surfaces did decrease the accuracy of readings because of the greater distance between the artifact and the detector. Our results provide new insight into the stability of supply networks and markets well into the Colonial period as well as the homogenizing tendencies of the Aztec market system.     

An experimental approach to the study of interpersonal violence in Northeastern Patagonia (Argentina), during the late Holocene

This paper incorporates an experimental approach to the study of violence patterns in Northeastern Patagonia (Argentina) during the late Holocene. The underlying hypothesis considers a close association between socio-ecologic alterations during the Medieval Climatic Anomaly (MCA) (ca. 1150-600 years BP; Stine, 1994, 2000) and a probable increase in conflict levels. In order to test this hypothesis, human skulls (n = 986) were analyzed for bone lesions, discriminating late bone lesions, such as those produced by metal tools. The experimental approach used swine (Sus scrofa domestica) skulls, as proxies for human skulls, and incorporated original sabers. From this discriminating analysis, it can be inferred that no significant increase in violence signs were recorded until the first stages of Hispanic-indigenous contact (first half of 17th century). These findings emphasize the need for a revision of the implications of the dynamics of human populations in Northeastern Patagonia during the late Holocene.     

Identification of fragmentary bone from the Pacific

We explore bone microstructure for taxonomic identification of archaeological bones too fragmentary to permit secure identification on morphological grounds. Backscattered electron (BSE) imaging is used to observe bone tissue types and the arrangement of vascular canals, and to facilitate quantification of osteonal canal dimensions. Examination of known examples of relevant taxa (humans [n = 8], pigs [n = 4] and dogs [n = 4]) shows significant differences among them. When the results of this examination are applied to a blind test of modern and archaeological specimens (humans [n = 8], pigs [n = 2]), 100% of specimens are identified correctly. The approach is applied to 13 morphologically unidentifiable fragments from Hawai’i and Fiji to evaluate its potential for identifying bone tools and to increase the number of samples available for dietary analysis. Potential applications of the approach for other contexts are discussed.     

A radiocarbon chronology for Sāmoan prehistory

The corpus of radiocarbon dates for Sāmoan archaeology has grown exponentially since the pioneering work of Green and Davidson in the 1960s, enabling us to re-analyze the archipelago's cultural chronology. A reliable and valid radiocarbon chronology forms the basis for describing and explaining cultural variability and change in the central Pacific. Towards that end, in this paper we compile the available radiocarbon dates from published and unpublished (“grey literature”) sources. We critically evaluate 236 radiocarbon dates following a chronometric hygiene protocol to identify the most secure and reliable age estimates. We accept 147 dates (62.3%) as a means of addressing two significant issues for Sāmoan prehistory: (1) the chronology of settlement and human expansion across the archipelago pre-2000 cal BP, which relates to issues of Lapita colonization, and the effect of island geomorphology on settlement; and (2) analysis of the so-called “Dark Ages” (ca. 1500–1000 cal BP), a period relevant to issues of social complexity and East Polynesian settlement. Our research highlights the need for a rigorous sampling protocol for radiocarbon dating.     

Sr/Sr variability in Puerto Rico: geological complexity and the study of paleomobility

The temptation to use biogeochemical techniques to resolve issues of paleomigration is evident and well intentioned. Knowledge of radiogenic strontium isotope baselines in a region of interest is a sine qua non of such archaeological studies of paleomobility. Here, we present the first detailed study of baseline ⁸⁷Sr/⁸⁶Sr values for the island of Puerto Rico. The high degree of ⁸⁷Sr/⁸⁶Sr variability present in this corpus of modern Puerto Rican bedrock and terrestrial malacological samples (0.70406–0.70909) is a testament to the complex geology of that island. This diversity of ⁸⁷Sr/⁸⁶Sr values makes parsing issues of origin a difficult and highly contingent task. Given these complexities, regional studies seeking to assess paleomigration by such isotopic means should proceed with a great deal of caution.     

Problems of Identification and Quantification in Archaeozoological Analysis,Part I: Insights from a Blind Test

In archaeozoology, counts are generally considered as replicable data that accurately represent the initial abundances of elements, individuals, or taxa, although perhaps only at the ordinal scale. However, few studies have tested these assumptions with control data. To improve our knowledge of these issues, we conducted a blind test that involved the analysis of two large experimental samples composed of modern ungulate specimens of known element and taxon. Because the samples differed in level of fragmentation, the blind test provides substantial information on the impact of bone processing on faunal identification and quantification. Our results suggest that Number of Identified SPecimens (NISP) and Minimum Number of Elements (MNE) provide measures of abundance for whole assemblages and for samples limited to non-long bones that are both replicable and accurate at the ratio scale. However, the same metrics generally failed, even at the ordinal level, to predict abundances in analyses restricted to long bones and long bone portions. Given these mixed results, it seems judicious, in agreement with the current majority view among archaeozoologists, to treat faunal tallies as ordinal-level information. Despite issues of reproducibility and the difficulty of aggregating counts with MNE, the blind test also indicates that this measure is more robust at predicting skeletal abundances than NISP. Substantial variations in rates of long bone fragmentation and identification probably explain the poorer performance of NISP in the blind test.     

Macro- and micro-archaeobotanical study of a vessel content from a Late Neolithic structured deposition from southeastern Hungary

A well-preserved assemblage of pottery and a broken stone artefact were excavated within a long house in the southern part of Tiszasziget, near the town of Szeged, Hungary. The settlement had been inhabited by the Late Neolithic Tisza culture around 5000–4500 BC. Based on the position of the finds it is suggested that the objects represent an ideologically-charged structured deposition. A piece of organic residue found in a mug (No. 18) with three-fold articulation has been subjected to macro- and microfloral analysis. After precise sampling of the residue, the standard methods to recover organic and inorganic plant remains were utilised. Based on the macrofloral and amino acid content analysis, it is suggested that the organic remains were pieces of fermented pastry made of cereal flour. The recovered silicified tissues and articulated phytoliths were subjected to morphometric measurements, which revealed that the food remain placed in the structured deposition was prepared of Triticum and – probably wild – Avena species. Starch granules of cereals were also detected, whilst the palynological evidence supports morphologies most likely to be related to the accompanying weed flora. The fortunate survival of the organic matter and the complex macro- and micro-archaeobotanical approach provided an unique opportunity to gain a better insight to the food preparation of Late Neolithic communities of the Carpathian Basin.     

An exploration of character traits and linear measurements for sexing mountain gazelle (Gazella gazella) skeletons

The skeletal elements of mountain gazelle (Gazella gazella) have proven difficult to sex with statistical confidence due to wide overlap in the body size of the two sexes. We studied a sample of 53 modern mountain gazelle skeletons to determine which character traits and metric measurements best predict sex. The success of the character traits was determined using blind tests while the metrics were examined using discriminant function analysis. The most useful elements include the previously identified horn core, pubis and atlas, but also some new bone portions that preserve well in the archaeological record (e.g., distal tibia, distal metacarpal and metatarsal, and second phalanx). Surprisingly, two elements commonly used in sexing analyses (distal humerus and astragalus) were not among the most effective elements. Although cutting points and discriminant functions for sexing gazelle bone portions are presented here, they do not account for potential body size change and thus are not suited for direct application to archaeological assemblages. Instead, we provide guidelines for application to archaeological gazelle assemblages, most importantly a regression analysis that considers the sex ratios obtained from multiple measurements to predict the sex ratio of archaeological gazelle populations.     

The persistence of caffeine in experimentally produced black drink residues

Black drink is a native North American caffeinated tea produced from the leaves of Ilex vomitoria. The beverage was an important part of prehistoric Southeastern culture, as it was the only native source of caffeine in North America. The leaves of I. vomitoria were, therefore, a potentially valuable trade resource during the period. As such, the ability to identify archaeological black drink residues is useful to Southeastern archaeologists. In order to determine the plausibility of detecting I. vomitoria in residues, black drink was repeatedly produced in experimental unglazed pottery. The resulting potsherds were buried in several environmental contexts, recovered, and underwent absorbed pottery residue analysis. After two months of burial in three different soil types, plus a control stored in the freezer, caffeine was well-preserved in all sherds, suggesting that caffeine is a potentially useful biomarker for the detection of black drink.     

Developing FTIR Microspectroscopy for the Analysis of Animal-Tissue Residues on Stone Tools

The analysis of microscopic residues on stone tools provides one of the most direct ways to reconstruct the functions of such artifacts. However, new methods are needed to strengthen residue identifications based upon visible-light microscopy. In this work, we establish that reflectance Fourier-transform infrared microspectroscopy (FTIRM) can be used to document IR spectra of animal-tissue residues on experimental stone tools. First, we present a set of reflectance FTIRM standards for the most commonly identified animal-tissue residues on stone tools: skin, meat, fat, hair, blood, feather barbules, fish scales, and bone. We provide spectral peak assignments for each residue and demonstrate that high-quality reflectance FTIRM spectra can be generated under ideal circumstances. Second, we document the spectra for these residues when they are located on a stone substrate such as flint or obsidian. We discuss procedures for correcting spectra that are affected by specular reflection and explain the effects of spectral interference from the stone. Our results show that reflectance FTIRM is sensitive to small intra-sample differences in composition. This means that it will record the effects of decomposition in ancient residues. The methodological developments we present here will help lithic residue analysts incorporate in situ reflectance FTIRM into their analysis protocols to strengthen identifications.     

Experimental micromorphology in Tierra del Fuego (Argentina): building a reference collection for the study of shell middens in cold climates

Commonly used in archaeological contexts, micromorphology did not see a parallel advance in the field of experimental archaeology. Drawing from early work conducted in the 1990’s on ethnohistoric sites in the Beagle Channel, we analyze a set of 25 thin sections taken from control features and experimental tests. The control features include animal pathways and environmental contexts (beach samples, forest litter, soils from the proximities of archaeological sites), while the experimental samples comprise anthropic structures, such as hearths, and valves of Mytilus edulis (the most important component of shell middens in the region) heated from 200 °C to 800 °C. Their micromorphological study constitutes a modern analogue to assist archaeologists studying site formation and ethnographical settings in cold climates, with particular emphasis on shell midden contexts.     

Middle Stone Age pièces esquillées from Sibudu Cave,South Africa: an initial micro-residue study

In this paper I present the results of a micro-residue study conducted on ten pièces esquillées (scaled pieces) from Sibudu Cave, South Africa. These artefacts are associated with the Howiesons Poort Industry (∼61.7 and ∼64.7 ka years ago at Sibudu), representing part of the later phase of the Middle Stone Age. Until now, it was unclear on what these pieces were used, and whether they were functional. Previous experimental use-wear work tentatively pointed towards bone processing. However, replication work on stone tool production technology suggests that pièces esquillées are merely the by/end-product of bipolar knapping. I used residue analysis on the Sibudu artefacts because this alternative method has the potential to identify if they were used, and if so, illuminate the specific materials the pieces were used on. Although the sample is small, all the pièces esquillées reveal a clear animal processing signal. There are some bone deposits on the utilised edges that may substantiate bone processing, or perhaps a bone hammer was used with them, but additional study, including Later Stone Age artefacts, is needed to assess the feasibility of these observations. It remains possible that the artefacts are core reduced pieces that were subsequently used as tools or simply knapped with a bone hammer.     

Age‐at‐death assessment using the os pubis and the auricular surface of the ilium: a test on an identified Asian sample

This paper reviews the results of blind tests of two morphological methods of age‐at‐death estimation. These tests were performed on a known age‐at‐death and sex sample taken from a collection of a Thai population. The first technique is based on the age related changes of the pubic symphysis according to the Suchey‐Brooks system, and the other concerns the metamorphosis of the auricular surface of the ilium elaborated by Lovejoy and colleagues. This is the first time that these methods have been tested on skeletal material from Asia. The results indicate that, for both methods, bias and inaccuracy increase with age and true age tends to be underestimated. As a consequence, age‐at‐death assessment based on these two techniques should be avoided on Asian archaeological series or forensic cases. Copyright © 2004 John Wiley & Sons, Ltd.     

Characterisation and blind testing of radiocarbon dating of cremated bone

The success of radiocarbon dating of burned or cremated bones depends on the exposed temperature during burning and the degree of re-crystallisation of the inorganic bone matrix. We present a method for characterisation of likely cremated bones by employing visual inspection, infrared spectrometry and carbon stable isotope analysis on the bio-apatite fraction. The method of radiocarbon dating of cremated bones was tested by dating paired samples of bone and associated context materials such as pitch, charcoal and a dendrochronologically dated oak coffin. The dating of these paired test samples were largely performed as blind tests and showed excellent agreement between pitch and bone. The weighted mean age difference of all test samples is observed to −9 ± 60 ¹⁴C yr. To test the indicators and the effects of the degree of burning, a Late-Neolithic human individual has been studied, as this individual exhibits the full spectrum from low temperature burning (charred) to high temperature (“cremated”) from one end of a single bone to the other. This is reflected as a marked step in numerous parameters as well as in a significant difference in ¹⁴C age between the charred and the cremated bone samples.     

Equivalent dose distributions from single grains of quartz at Sibudu,South Africa: context,causes and consequences for optical dating of archaeological deposits

Optical ages for 14 sediment samples collected from the post-Howiesons Poort, late Middle Stone Age (MSA) and final MSA deposits at Sibudu, KwaZulu-Natal, South Africa were reported in a companion paper (Jacobs, Z., Wintle, A.G., Duller, G.A.T., Roberts, R.G., Wadley, L. New ages for the post-Howiesons Poort, late and final Middle Stone Age at Sibudu, South Africa. Journal of Archaeological Science, 2008). These ages were based on equivalent dose (D_e) distributions that were overdispersed. In this paper, we investigate factors both internal and external to the grains that may contribute to such higher than expected overdispersion in single grain D_e values. Intrinsic factors accounted for some, but not all, of the observed scatter, and application of a set of rejection criteria filtered grains for which erroneous D_e values would otherwise be calculated. We investigated sediment mixing and differences in the beta dose received by individual grains in their burial environment as two likely reasons for the observed overdispersion. The scatter in D_e distributions for all the samples is best explained by grains that were deposited at the same time and which were well bleached, but that subsequently received a range of beta doses. A procedure is presented for adjusting the measured beta dose rate, and its associated error. We show that using a combination of single grain OSL measurements of D_e, the finite mixture model and adjustment of the beta dose rate, result in stratigraphically consistent ages. These ages are more consistent than the ages obtained from multiple grain aliquot D_e values and the average dose rates for each sample; the multiple grain ages are about 10% older, partly because of the variable dose rate and partly because these aliquots contained grains with undesirable OSL characteristics.     

First molecular identification of a hafting adhesive in the Late Howiesons Poort at Diepkloof Rock Shelter (Western Cape,South Africa)

The hafting of tools using adhesive is one of the innovative features that characterizes the southern African Middle Stone Age. This technology has mainstream implications but remains insufficiently documented, largely due to unequal organic preservation and non-adapted analytical procedures. A notable exception is provided by the recent results from the site of Sibudu (Lombard, 2006; Wadley et al., 2009).