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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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Least cost path analysis of early maritime movement on the Pacific Northwest Coast

Posted on November 29, 2016 by ARCAS

Publication date: February 2017Source:Journal of Archaeological Science, Volume 78 Author(s): Robert Gustas, Kisha SupernantIn this paper, we present a new method for modeling past maritime movement events using least cost path analysis. Nontraditional measures of movement cost, including cultural, environmental, and physiological variables, were calculated. Using multiple cost-weighting scenarios, spatial resolutions, and different considerations of overland travel, movement routes were predicted for five Pacific Northwest Coast study areas. This work uses a new application of least cost path analysis to seascapes and marine movement and the results have led to a better understanding of migration during the Late Pleistocene and Holocene. The resulting routes were systematically analyzed and compared to determine which produced the results most likely to predict high-use coastal movement corridors. We found that modeling scenarios where culturally derived costs of movement were highly weighted and in which overland travel was very costly produced the best predictions of possible past movement events. These models show that predicted routes cluster in distinct patterns which are influenced by the geography of the seascape through which the movement event is taking place and that areas of high traffic are most likely to be located immediately offshore and to the south of islands as well as in the spaces between landmasses. This knowledge increases our ability to predict the location of drowned sites on the Northwest Coast and is important in contemporary archaeology because it can help locate new sites in a landscape that has radically changed over the last 20,000 years. GIS analysis can reveal new sites hidden by changing sea levels, which may not be easily located using traditional forms of site prospection. Accurate modeling of maritime movement opens many coastal areas to increased archaeological exploration and has the potential for the discovery of new sites in drowned locations.

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Hemorrhagic fever virus, human blood, and tissues in Iron Age mortuary vessels

Posted on November 28, 2016 by ARCAS

Publication date: February 2017Source:Journal of Archaeological Science, Volume 78 Author(s): Conner J. Wiktorowicz, Bettina Arnold, John E. Wiktorowicz, Matthew L. Murray, Alexander KuroskyThis study identifies and interprets the proteins present on sherds from six ceramic mortuary vessels from a burial mound near the Heuneburg, an early Iron Age (750–400 BCE) hillfort in southwest Germany, using a novel adaptation of proteomic analysis that identified 166 proteins with high confidence. Surprisingly, among the identified proteins were peptides from Crimean-Congo hemorrhagic fever virus (CCHFV), a pathogen previously unknown in this geographic region and time period, as well as peptides from human blood and tissues. These results highlight the first example of a viral cause of death of at least one high-status individual from the Iron Age west-central Europe and provide the first archaeological evidence for the interment of human organs in mortuary vessels in the region. We also demonstrate the suitability and value of a proteomics approach for discovery-based residue analysis of archaeological ceramic vessels and reveal how identification of adsorbed proteins can provide insight into prehistoric mortuary practices.

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Palaeolithic and prehistoric dogs and Pleistocene wolves from Yakutia: Identification of isolated skulls

Posted on November 27, 2016 by ARCAS

Publication date: February 2017Source:Journal of Archaeological Science, Volume 78 Author(s): Mietje Germonpré, Sergey Fedorov, Petr Danilov, Patrik Galeta, Elodie-Laure Jimenez, Mikhail Sablin, Robert J. LoseyFour isolated canid skulls from four sites (Badyarikha River, Tirekhtyakh River, Ulakhan Sular, Malyi Lyakhovsky Island) in the Sakha Republic of northern Siberia are here described. Three specimens date from the Pleistocene and range in age from more than 50,000 years to about 17,200 years old, the fourth specimen is about 950 years old. The Yakutian canid skulls are compared with Palaeolithic dogs, recent Northern dogs, Pleistocene wolves and recent Northern wolves by multivariate analyses of standardised cranial measurements in order to determine with which reference group they have the closest affinity. These analyses permitted to identify the Tirekhtyakh River specimen as a Pleistocene wolf. The Ulakhan Sular specimen resembles the Palaeolithic dogs and the Malyi Lyakhvosky specimen the recent Northern dogs. The Badyarikha River skull falls in between groups. The archaeological implications of the presence of ancient canid specimens resembling Palaeolithic and early dogs in arctic northeast Asia are discussed.

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