News

Publication date: January 2018Source:Journal of Archaeological Science, Volume 89 Author(s): Dominique Sordoillet, Olivier Weller, Nicolas Rouge, Martine Buatier, Jean-Pierre SizunSince the Early Neolithic, salt has played an important role in the social and economic development of populations. Consequently, the study and comprehension of salt management strategies have become a significant component of current archaeological research. This study is part of an interdisciplinary research program consisting of excavations and detailed analyses on two Early Neolithic salt working sites situated in the sub-Carpathian region of Romania, Lunca and Ţolici (county Neamţ). These remarkably well-preserved sites are characterised by stratified deposits several meters thick. Detailed stratigraphic descriptions were followed by optical microscopy analysis (soil micromorphology) and scanning electron microscopy (SEM) coupled with geochemical analysis (EDS). The aim of these analyses was to identify specific sedimentary, petrographic and chemical characteristics that could be linked to salt working process. The results enable us to describe the main site formation process over time and to detect chemical components of edible salt (Na and Cl) in Early Neolithic ashes. These new data consolidate previous interpretations of the operating procedures implemented from the Early Neolithic to the Bronze Age. Two techniques appear to have been preferentially adopted: pouring natural brine onto combustion structures during the Early Neolithic and evaporation in specific ceramic containers from the Chalcolithic onwards.

Publication date: Available online 6 December 2017Source:Journal of Archaeological Science Author(s): Erik Otárola-Castillo, Melissa G. Torquato, Hannah C. Hawkins, Emma James, Jacob A. Harris, Curtis W. Marean, Shannon P. McPherron, Jessica C. ThompsonStudies of bone surface modifications (BSMs) such as cut marks are crucial to our understanding of human and earlier hominin subsistence behavior. Over the last several decades, however, BSM identification has remained contentious, particularly in terms of identifying the earliest instances of hominin butchery; there has been a lack of consensus over how to identify or differentiate marks made by human and non-human actors and varying effectors. Most investigations have relied on morphology to identify butchery marks and their patterning. This includes cut marks, one of the most significant human marks. Attempts to discriminate cut marks from other types of marks have employed a variety of techniques, ranging from subjectively characterizing cut mark morphology using the naked eye, to using high-powered microscopy such as scanning electron microscopy (SEM) or micro-photogrammetry. More recent approaches use 3D datasets to obtain even more detailed information about mark attributes, and apply those to the fossil record. Although 3D datasets open promising new avenues for investigation, analyses of these datasets have not yet taken advantage of the full 3D surface morphology of BSM. Rather, selected cross-sectional slices of 3D scans have been used as proxies for overall shape. Here we demonstrate that 3D geometric morphometrics (GM), under the “Procrustes paradigm” and coupled with a Bayesian approach, probabilistically discriminates between marks caused by different butchery behaviors. At the same time, this approach provides a complete set of 3D morphological measurements and descriptions. Our results strengthen statistical confidence in cut mark identification and offer a novel approach that can be used to discriminate subtle differences between cut mark types in the fossil record. Furthermore, this study provides an incipient digital library with which to make future quantitative comparisons to archaeological examples, including contentious specimens that are key to understanding the earliest hominin butchery.

Publication date: January 2018Source:Journal of Archaeological Science, Volume 89 Author(s): M.G. Canti, C. NicosiaFaecal spherulites are a common indicator of dung in archaeological deposits and most of the basic processes of their formation and taphonomy have been explained. However, a darkened form is also regularly found, ranging from slightly transparent through to completely opaque. These have been less well studied, so we set out here to understand what actually causes the darkening and to determine the range of conditions required to produce the changes.Darkened spherulites were successfully created by heating dung to between 500 °C and 700 °C with the gaseous products constrained. The maximum production in our experiments was at 600 °C. The darkened spherulites often expanded during the alteration process and some of the expanded ones become distorted. SEM examination was only possible through destructive preparation processes, but examples were found showing expansion beyond the normal size range. These had a distinctive internal structure characterised by very fine crystallinity and larger scale fracturing, perhaps resulting from organic matter loss and/or CaCO3 alteration. Prolonged oxidative heating failed to remove the darkening, leading to the possibility that it is partly a structural phenomenon, with opacification arising from compound relief.Based on these findings, darkened spherulites can now be confidently interpreted as; resulting from dung being heated in conditions of limited gaseous exchange to between 500 and 700 °C, then not heated again beyond ca. 700 °C. These sorts of conditions could occur, around the edge of, or beneath, any fire where fresh dung is; being burned or where the existing stratigraphy has a dung component.

Publication date: November 2017Source:Journal of Archaeological Science, Volume 87

Publication date: December 2017Source:Journal of Archaeological Science, Volume 88

Publication date: January 2018Source:Journal of Archaeological Science, Volume 89 Author(s): Keith W. Kintigh, Scott E. IngramIt is commonplace to assert causal relationships between episodes of extreme climate with dramatic cultural shifts. We explore the problem of statistically assessing the correspondence between episodes of extreme climate (such as droughts) and cultural events (such as depopulation) they are purported to explain. In order to do this: 1) We describe a method that permits the objective identification of climate extremes in a way that is independent of their supposed causal outcomes; 2) We discuss how we identify and date cultural transitions of interest; 3) We explore a variety of decision rules for determining whether or not there is a match between a given extreme climate interval and the interval during which a transition began; and 4) We propose an intuitive Monte Carlo approach to statistically assess the observed correspondence between the climate extremes and the cultural transitions. Our application does not indicate statistical support for a linkage between intervals of extreme climate and major transitions in any of the seven cultural traditions in the Southwest US that we examined.

Publication date: January 2018Source:Journal of Archaeological Science, Volume 89 Author(s): Øyvind Ødegård, Roy E. Hansen, Hanumant Singh, Thijs J. MaarleveldMarine archaeological surveying in deep waters has so far been challenging, mainly due to operational and technological constraints. The standard tool has been Side Scan Sonar (SSS) towed behind a surface vessel. Synthetic Aperture Sonar (SAS) technology is not subject to the traditional range/resolution trade-off, and produces results of considerably higher quality than traditional SSS. In 2015 and 2016 a comprehensive mapping of wrecks in Skagerrak, a large deepwater area off the south coast of Norway was undertaken, using an interferometric SAS system deployed on an autonomous underwater vehicle. By examining data from two passes of one of the many historical wrecks that were detected in the survey area, we demonstrate how SAS can be used to produce very high resolution imagery and bathymetry of wreck sites. Furthermore, post processing techniques are applied to exploit the high information content inherent in SAS data, enhancing aspects of the data for relevant archaeological analysis and interpretation. We show in this paper how SAS technology represents significant improvements in our abilities to conduct high quality and high resolution seabed mapping. The adoption of this technology will both benefit archaeological research and provide knowledge for better decision making in underwater cultural heritage management.

Publication date: January 2018Source:Journal of Archaeological Science, Volume 89 Author(s): Carolina Cucart-Mora, Sergi Lozano, Javier Fernández-López de PabloThe Middle to Upper Palaeolithic transition was a process of cultural and biological replacement, considered a turning point in human evolutionary history. Various hypotheses have been used to explain the disappearance of Neanderthals from Eurasia. However, very few studies have explicitly examined the causative role of demography on Neanderthal and anatomically modern humans (AMH) interaction. Here we use an integrative method based on computational modelling and the analysis of archaeological data to construct an agent based model that explores the influence of demographic variables (birth and death rates) and mobility (home range size) on the bio-cultural interaction between AMH and Neanderthals during the transition from the Middle to Upper Palaeolithic on the Iberian Peninsula (50 ka to 30 ka BP). Our simulation results are consistent with the current radiocarbon framework for the disappearance of Neanderthals in this region. This suggest that the extinction of Neanderthals could be explained by inter-specific differences in demographic behaviour and mobility patterns compared with AMH.

Publication date: December 2017Source:Journal of Archaeological Science, Volume 88 Author(s): Marianne Mödlinger, Maikel H.G. Kuijpers, Dennis Braekmans, Daniel BergerThe colors of copper alloys are of particular interest in archaeology and can be characterized quantitatively and systematically. The CIELAB color system can determine different color parameters such as a*, b*, and L* by means of a spectrophotometer that describes the surface color. Additional information such as C* and h values can be calculated from these parameters which allows one to build a set of color-composition diagrams that connects chromaticity and alloy composition. With such data it is possible to estimate the color of prehistoric metal artifacts with similar chemical composition. A better understanding of the association between metallurgical composition and color will aid the research of prehistoric metalwork because choices in production and use of metal were likely influenced by this particular quality of metal.

Publication date: December 2017Source:Journal of Archaeological Science, Volume 88 Author(s): Rhy McMillan, Dominique Weis, Marghaleray Amini, Dominique BonjeanErosional processes often rework materials of different ages into the same sedimentary facies, producing time-averaged deposits. Such reworking is common at archaeological sites, and researchers must consider the resulting time-averaging effects when using natural stratigraphy to situate artifacts and remains in time. At Scladina Cave, a Neandertal site in Belgium, we developed a method for identifying reworked facies and the stratigraphic provenance of mammal bones based on their post-mortem trace element characteristics and crystallinity. We collected sixty-two faunal remains from throughout the site’s sedimentary sequence and analyzed them for trace element concentrations and crystallinity with laser ablation inductively coupled plasma mass spectrometry and Raman spectroscopy. Our novel approach, the ‘Perio-spot’ technique, quantifies the trace element characteristics and crystallinity from the most diagenetically altered part of a bone with high spatial resolution. Trace element concentrations, rare earth element patterns, and crystallinity of ‘Perio-spots’ correlate throughout the Scladina sedimentary sequence. Based on stratigraphic trends in bone chemistry and crystallinity, we subdivide the Scladina sequence into two successive periods of early diagenesis, a period of later diagenesis, and a transitional period between the early and later diagenesis periods. The period boundaries also correspond to major climatic fluctuations identified in the site’s stratigraphy by other means (e.g., palynology and heavy mineralogy). The stratigraphic provenance of nine cave bear femora support the confinement of reworking to within each of the diagenetic periods; the provenance of two indeterminate faunal remains that visually resemble the taphonomic alteration of the Scladina Neandertal (taphonomic proxies) suggest that the individual may be significantly older than previously hypothesized. Evaluating the temporal integrity of exhumed assemblages and the original sedimentary context of bones with our method is thus a valuable addition to archaeological analyses, especially beyond the temporal range of radiocarbon dating or in contexts with very low preservation potential of organic materials.