The digital radiography of archaeological pottery: Program and protocols for the analysis of production

Posted on December 29, 2016 by ARCAS

Publication date: February 2017Source:Journal of Archaeological Science, Volume 78 Author(s): A.F. Greene, C.W. Hartley, P.N. Doumani Dupuy, M. ChinanderArchaeologists collaborating with material scientists at Argonne National Laboratory (ANL) as part of the Making of Ancient Eurasia (MAE) Project have developed formal methodological standards for the assemblage-based digital radiographic (DR) analysis of archaeological pottery. While analog radiography of pottery (X-radiography, Xeroradiography, etc.) has functioned as a common disciplinary tool for some time, inaccessibility, obsolescence, and significantly enhanced functionality have made DR instrumentation increasingly attractive and vital. This article presents the theoretical underpinnings, technique development, and resultant protocols that allow digital radiography to analyze very large assemblages and provide quantitative data sets that act as true counterparts to geochemical and mineralogical ones. As a technique of structural pottery evaluation, DR is particularly suited to the analysis of ceramic paste preparation and vessel formation, providing lines of evidence that can flesh out neglected portions of the chaîne opératoire, augment existing geochemical or typological classifications, and help more deeply characterize various potting traditions. Such datasets are most useful to scholars interested in harnessing the ability of the pottery “life cycle” to shed light on economic life, learning frameworks, and human social differences and group identities. The technical capacities and analytical potential of DR are demonstrated through several test analyses of ancient Chinese pottery, to be followed by more extensive case studies in draft. Prospects for closely related, three-dimensional X-ray computed tomographic approaches are also discussed.

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The adoption of pottery by north-east European hunter-gatherers: Evidence from lipid residue analysis

Posted on December 25, 2016 by ARCAS

Publication date: February 2017Source:Journal of Archaeological Science, Volume 78 Author(s): Ester Oras, Alexandre Lucquin, Lembi Lõugas, Mari Tõrv, Aivar Kriiska, Oliver E. CraigPottery was adopted by hunter-gatherers in the Eastern Baltic at the end of the 6th millennium cal BC. To examine the motivations for this cultural and technological shift, here we report the organic residue analysis of ceramic vessels from the earliest pottery horizon (Narva) in this region. A combined approach using GC-MS, GC-C-IRMS and bulk IRMS of residues absorbed into the ceramic and charred surface deposits was employed. The results show that despite variable preservation, Narva ceramic vessels were preferentially used for processing aquatic products. We argue that pottery was part of a new Late Mesolithic subsistence strategy which included more intensive exploitation of aquatic foods and may have had important implications, such as increased sedentism and population growth.

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Facilitating tree-ring dating of historic conifer timbers using Blue Intensity

Posted on December 24, 2016 by ARCAS

Publication date: February 2017Source:Journal of Archaeological Science, Volume 78 Author(s): Rob Wilson, David Wilson, Miloš Rydval, Anne Crone, Ulf Büntgen, Sylvie Clark, Janet Ehmer, Emma Forbes, Mauricio Fuentes, Björn E. Gunnarson, Hans W. Linderholm, Kurt Nicolussi, Cheryl Wood, Coralie MillsDendroarchaeology almost exclusively uses ring-width (RW) data for dating historical structures and artefacts. Such data can be used to date tree-ring sequences when regional climate dominates RW variability. However, the signal in RW data can be obscured due to site specific ecological influences (natural and anthropogenic) that impact crossdating success. In this paper, using data from Scotland, we introduce a novel tree-ring parameter (Blue Intensity – BI) and explore its utility for facilitating dendro-historical dating of conifer samples. BI is similar to latewood density as they both reflect the combined hemicellulose, cellulose and lignin content in the latewood cell walls of conifer species and the amount of these compounds is strongly controlled, at least for trees growing in temperature limited locations, by late summer temperatures. BI not only expresses a strong climate signal, but is also less impacted by site specific ecological influences. It can be concurrently produced with RW data from images of finely sanded conifer samples but at a significantly reduced cost compared to traditional latewood density. Our study shows that the probability of successfully crossdating historical samples is greatly increased using BI compared to RW. Furthermore, due to the large spatial extent of the summer temperature signal expressed by such data, a sparse multi-species conifer network of long BI chronologies across Europe could be used to date and loosely provenance imported material.

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Identifying domestic horses, donkeys and hybrids from archaeological deposits: A 3D morphological investigation on skeletons

Posted on December 22, 2016 by ARCAS

Publication date: February 2017Source:Journal of Archaeological Science, Volume 78 Author(s): Pauline Hanot, Claude Guintard, Sébastien Lepetz, Raphaël CornetteThe first evidence for the domestication of donkeys (Equus asinus) dates back to at least 6000-5000 BP in Northeast Africa, and their dispersion is attributed to the ancient Romans. Latin authors described donkeys as being particularly suitable for the transport of goods and farm work. In addition, they were also bred to produce prized hybrids, particularly mules, which were perfectly adapted to the long-distance transport of people and goods. However, although the historical sources extensively describe their economic importance, both donkey and hybrid remains are surprisingly scarce in the archaeological record. This apparent contradiction is probably due to the difficulties involved in correctly identifying their bones: relatively few bones displaying morphological and metrical criteria can be used for identification, so it is often based purely on bone size. The aim of this study, therefore, is to propose solutions to identify domestic equid bones using 3D geometric morphometrics on isolated and combinations of anatomical elements. A set of 3D coordinates were registered on the 18 main skull and limb bones of 111 modern reference specimens (i.e. 42 horses, 44 donkeys and 25 hybrids). In this paper, we present the classification rate obtained on this reference sample using the k-Nearest Neighbors algorithm. The application of this method on archaeological skeletons from Roman to modern sites is also presented. The percentage of correctly classified specimens was between 77% and 95% for all 18 bones, and higher than 80% for 10 of the fragmentation patterns we defined. Using a combination of several bones enabled us to increase the rate of correct reclassification to a maximum of 97%. The application to archaeological skeletons proved the ability of this method to identify domestic horses and donkeys from archaeological samples. Correspondingly, some bones, and especially combinations of bones, provided good rates to identify hybrids. This method has proved reliable in detecting the presence of donkeys and hybrids from the archaeological samples of equid bones, and should enrich our knowledge regarding their spread across Europe.

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Farmer fidelity in the Canary Islands revealed by ancient DNA from prehistoric seeds

Posted on December 19, 2016 by ARCAS

Publication date: February 2017Source:Journal of Archaeological Science, Volume 78 Author(s): Jenny Hagenblad, Jacob Morales, Matti W. Leino, Amelia C. Rodríguez-RodríguezThe Canary Islands were settled in the first millennium AD by colonizers likely originating from North Africa. The settlers developed a farming economy with barley as the main crop. Archaeological evidence suggests the islands then remained isolated until European sea-travellers discovered and colonized them during the 14th and 15th centuries. Here we report a population study of ancient DNA from twenty-one archaeobotanical barley grains from Gran Canaria dating from 1050 to 1440 cal AD. The material showed exceptional DNA preservation and genotyping was carried out for 99 single nucleotide markers. In addition 101 extant landrace accessions from the Canary Islands and the western Mediterranean were genotyped. The archaeological material showed high genetic similarity to extant landraces from the Canary Islands. In contrast, accessions from the Canary Islands were highly differentiated from both Iberian and North African mainland barley. Within the Canary Islands, landraces from the easternmost islands were genetically differentiated from landraces from the western islands, corroborating the presence of pre-Hispanic barley cultivation on Lanzarote. The results demonstrate the potential of population genetic analyses of ancient DNA. They support the hypothesis of an original colonization, possibly from present day Morocco, and subsequent isolation of the islands and reveal a farmer fidelity to the local barley that has lasted for centuries.

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Beyond size: The potential of a geometric morphometric analysis of shape and form for the assessment of sex in hand stencils in rock art

Posted on December 13, 2016 by ARCAS

Publication date: Available online 13 December 2016Source:Journal of Archaeological Science Author(s): Emma Nelson, Jason Hall, Patrick Randolph-Quinney, Anthony SinclairHand stencils are some of the most enduring images in Upper Palaeolithic rock art sites across the world; the earliest have been dated to over 40 Kya in Sulawesi and 37 Kya in Europe. The analysis of these marks may permit us to know more about who was involved in the making the of prehistoric images as well as expanding the literature on the evolution of human behaviour. A number of researchers have previously attempted to identify the sex of the makers of Upper Palaeolithic hand stencils using methods based on hand size and digit length ratios obtained from digital or photo-based images of modern reference samples. Some analyses report that it was males who were responsible for the majority of hand stencils, whilst the most recent analysis determined that females produced the majority of hand stencils. Taken together, however, these studies generate contrasting and incompatible interpretations. In this study we critically review where we currently stand with methods of sexing the makers of hand stencils and the problems for the interpretation of hand markings of Palaeolithic age. We then present the results of a new method of predicting the sex of individuals from their hand stencils using a geometric morphometric approach that detects sexual differences in hand shape and hand form (size and shape). The method has the additional advantage of being able to detect these differences in both complete, as well as partial hand stencils. Finally we urge researchers to test this method on other ethnic groups and populations and consider ways of combining efforts towards a common goal of developing a robust, predictive methodology based on diverse modern samples before it is applied to Upper Palaeolithic hand stencils.

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Optically-stimulated luminescence profiling and dating of historic agricultural terraces in Catalonia (Spain)

Posted on December 6, 2016 by ARCAS

Publication date: February 2017Source:Journal of Archaeological Science, Volume 78 Author(s): Tim Kinnaird, Jordi Bolòs, Alex Turner, Sam TurnerDating agricultural terraces is a notoriously difficult problem for archaeologists. The frequent occurrence of residual material in terrace soils and the potential for post-depositional disturbance mean that conventional artefactual and lab-based dating methods often provide unreliable dates. In this paper we present a new technique using luminescence field profiling coupled with OSL dating to produce complete (relative) sequences of dates for sedimentary stratigraphies associated with agricultural terraces and earthworks. The method is demonstrated through a series of case-studies in western Catalonia, Spain, in which we reconstruct the formation sequence of earthwork features from the Middle Ages through to the present day. OSL profiling at the time of archaeological survey and excavation permitted spatially and temporally resolved sediment ‘chronologies’ to be generated, and provides the means to interpret the environmental and cultural archives contained in each. The case-studies presented here show that luminescence approaches are a valuable tool to reconstruct landscape histories.

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Editorial Board

Posted on December 4, 2016 by ARCAS

Publication date: December 2016Source:Journal of Archaeological Science, Volume 76

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A new method for extracting the insoluble occluded carbon in archaeological and modern phytoliths: Detection of 14C depleted carbon fraction and implications for radiocarbon dating

Posted on December 4, 2016 by ARCAS

Publication date: February 2017Source:Journal of Archaeological Science, Volume 78 Author(s): Yotam Asscher, Steve Weiner, Elisabetta BoarettoPhytolith-rich layers in archaeological sites constitute well defined stratigraphic horizons that would be invaluable if absolutely dated. Previous attempts to radiocarbon date phytoliths produced inconsistent results using plants with known ages. In this study a new approach to extract and analyze the silica occluded carbon was tested on well-dated archaeological contexts in Beth Shemesh and Tell es-Safi/Gath, and on modern wheat plants that grew in a controlled environment. Results show that by dissolving the silica using mild conditions, phytolith insoluble fractions can be extracted and their radiocarbon contents analyzed reproducibly. After phytolith dissolution, the remaining insoluble fractions with 10–30%C have radiocarbon concentrations that are statistically similar to associated charred seeds (within 2σ), and insoluble fractions with 40%C show concentrations that are identical to the seeds. These results show that the insoluble fraction of phytoliths is a suitable material for answering chronological questions.

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