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- Quina retouch does not maintain edge angle over reductionPublication . Lin, Sam C.; Marreiros, JoaoThe Quina scraper features an important role in the discussion of European Middle Palaeolithic variability. Explanations for its characteristic retouch and blank morphology have ranged from economic to functional and cultural considerations. One hypothesis is that Quina retouch maintains the edge angle of the retouched margin, allowing the upkeep of high cutting potential despite repeated resharpening. In this study, we examine this hypothesis by using a sample of scrapers from the Middle Palaeolithic site of Roc de Marsal in southwest France. The results show that, when the influence of reduction intensity and flake thickness are controlled, Quina retouch has no detectable impact on the retouched edge angle. Instead, the overall higher edge angles among Quina scrapers are a product of continuous reduction and the use of thicker blanks. We discuss possible factors underlying the occurrence of Quina retouch with respect to lithic economy and function.
- Understanding paleolithic human coastal adaptations in southwetern Iberian Peninsula (Paleocoast Project)Publication . Marreiros, Joao; Duarte, D. N.; Regala, Frederico; Dores, Tiago; Francisco, Rui; Soares, RicardoThe geological and geomorphological formations in the Atlantic shore of Southern Portugal in Algarve are characterized by karstic formations. Karstic features, such as natural caves and shelters, have long been seen as an attractive ecological and geological landscape to early human occupation during the Pleistocene and Early Holocene. The project PaleoCoast, Paleolithic Human Coastal Adaptations in Southwestern Iberian Peninsula, aims to locate and identify coastal karst formation, and assess its speleological and geological characterization, and archaeological potential. This poster introduces the PaleoCoast research project, including research scope, goals and methods, and an overview on the preliminary results from the pilot study conducted in 2017.
- Evaluating the microscopic effect of brushing stone tools as a cleaning procedurePublication . Pedergnana, Antonella; Calandra, Ivan; Bob, Konstantin; Gneisinger, Walter; Paixão, Eduardo; Schunk, Lisa; Hildebrandt, Andreas; Marreiros, JoaoCleaning stone tool surfaces is a common procedure in lithic studies. The first step widely applied at any archeological site (and/or at field laboratories) is the gross removal of sediment from the surfaces of artifacts. Lithic surface alterations due to mechanical action applied in wet or dry cleaning regimes have never been examined at a microscopic scale. This could have important implications in traceology, as any modern surface modifications inflicted on archeological artifacts might compromise their functional interpretations. The current trend toward quantification of use-wear traces makes the testing even more important, as even slight, apparently invisible surface alterations might be measured. In order to evaluate the impact of common cleaning procedures, we undertook a controlled experiment. The main aim of this experiment was to assess the effects that brushing actions applied for removing sediment particles have on flint and quartzite surfaces. All surfaces were analyzed with confocal microscopy before and after having been brushed to quantify possible changes in the micro-topography. Surface roughness parameters (ISO 25178-2 among others) were applied. Nine parameters changed significantly when mechanical actions were applied to lithic surfaces, meaning that some changes in the surface micro-topography were detected. Therefore, archeologists need to be cautious when applying prolonged mechanical actions for cleaning archeological stone tools.
- EcoPLis a pré-história no Rio Lis, da serra ao AtlânticoPublication . Pereira, Telmo; Carvalho, Vânia; Holliday, Trenton; Paixão, Eduardo; Monteiro, Patrícia; Évora, Marina; Marreiros, Joao; Assis, Sandra; Nora, David; Matias, Roxane; Simões, CarlosOur research focuses on the use of valleys that link the inland to the coast during Prehistory. Traditionally, research has studied rivers, coast and inland as separate landscapes, but the major characteristic of hunter-gatherers was mobility. In order to understand and reconstruct the evolution of human behaviour, our main goal is to answer the questions: “How, why and when did people circulate between these different ecological landscapes?” and “What was the impact of the major climatic shifts on that mobility?” To answer these questions our archaeological project includes survey, testing, and the excavation of archaeological sites, using high-resolution field and laboratory methodologies in order to contribute significantly to the understanding of ecological behaviour of Prehistoric populations, including extinct human species such as Neanderthals.
- Back to the edge: relative coordinate system for use-wear analysisPublication . Calandra, Ivan; Schunk, Lisa; Rodriguez, Alice; Gneisinger, Walter; Pedergnana, Antonella; Paixao, Eduardo; Pereira, Telmo; Iovita, Radu; Marreiros, JoaoUse-wear studies rely heavily on experiments and reference collections to infer the function of archeological artifacts. Sequential experiments, in particular, are necessary to understand how use-wear develops. Consequently, it is crucial to analyze the same location on the tool's surface during the course of an experiment. Being able to relocate the area of interest on a sample is also essential for reproducibility in use-wear studies. However, visual relocation has limited applicability and there is currently no easy and efficient alternative. Here we propose a simple protocol to create a coordinate system directly on the sample. Three ceramic beads that serve as reference markers are adhered onto the sample, either with epoxy resin or acrylic polymer. The former is easier to work with but the latter is reversible so it can be applied to archeological samples too. The microscope's software then relocates the position(s) of interest. We demonstrate the feasibility of this approach and measure its repeatability by imaging the same position on an experimental flint blade 10 times with two confocal microscopes. Our results show that the position can be relocated automatically with a horizontal positional repeatability of approximately 14% of the field of view. Quantitative surface texture measurements according to ISO 25178 vary due to this positional inaccuracy, but it is still unknown whether this variation would mask functional differences. Although still perfectible, we argue that this protocol represents an important step toward repeatability and reproducibility in experimental archeology, especially in use-wear studies.
- Territory and abiotic resources between 33 and 15.6 ka at Vale Boi (SW Portugal)Publication . Pereira, Telmo; Bicho, Nuno Gonçalo Viana Pereira Ferreira; Cascalheira, João; Infantini, Leandro; Marreiros, Joao; Paixão, Eduardo; Terradas, XavierThe environmental shifts during the Late Pleistocene had major influences in the landscape and, consequently, in the available resources. This had direct impact on human behavior and ecology, requiring people to constantly adjust to new economical conditions. In coastal areas, the retreat of the shoreline during the colder phases might have made available presently underwater raw material sources in the form of outcrops and gravels, eventually making it easier to gather lithic raw materials.In this paper, we present our preliminary results on the diachronic variability of raw materials in Vale Boi. Vale Boi is a coastal site, located 2.5 km from the present coastline, in the margins of a freshwater stream. The site has three different loci, all rich in lithics, fauna (including marine), bone tools, adornments, charcoal, and ochre, and evidence of continuous human occupation from c. 33 to 15.6 ka cal BP. This chronostratigraphic record makes it a perfect study case for the understanding of coastal populations' behavior and economy throughout the Upper Paleolithic.Our objective is to infer the territory of resources exploitation, landscape, and economic patterns. Raw material sources are usually fixed points on the landscape (in contrast to other resources such as fauna and flora) and, therefore, are one of the best ways of understanding how people moved in the landscape and, consequently, to infer past human behavior. We used a macroscopic approach in both the archaeological and the geological record in order to correlate sources and artifacts. Despite the absence of detailed quantitative data on each chert type, our results show that the hunteregatherers who occupied Vale Boi during the Upper Paleolithic not only used several raw materials but also a variety of sources of the same raw material. This happened both diachronically and synchronically, suggesting that not only the complete sequence as well as each archaeological layer seem to have had a considerable economic complexity with the use of adjacent and distal sources. With this paper, we aim to present updated information on the variability of raw materials at Vale Boi, including the chert assemblages, along with new chert sources in order to establish a basis for a future detailed study on the raw material sourcing at the site. (C) 2015 Elsevier Ltd and INQUA. All rights reserved.
- Rapid climatic events and long term cultural change: the case of the Portuguese Upper PaleolithicPublication . Bicho, Nuno Gonçalo Viana Pereira Ferreira; Cascalheira, João; Marreiros, Joao; Pereira, TelmoIn Western Europe, the Upper Paleolithic is marked by clear regional and diachronic technological differences. Some of these are most likely related with human adaptations to the Late Pleistocene environmental shifts. In this paper we focus on the rapid climatic change events and their influence on the Iberian regional ecology and vegetation cover. Based on those changes and their impact on the main Upper Paleolithic cultural phases in central and southern Portugal, we propose an explanatory model, to be tested in the future, where rapid climatic events, such as the D-O and Heinrich Events, have direct impact on the ecology and vegetation cover and this, in turn, cause changes in human adaptations in terms of mobility, settlement patterns, land use and technology. (C) 2015 Elsevier Ltd and INQUA. All rights reserved.
- Rethinking use-wear analysis and experimentation as applied to the study of past hominin tool usePublication . Marreiros, Joao; Calandra, Ivan; Gneisinger, Walter; Paixão, Eduardo; Pedergnana, Antonella; Schunk, LisaIn prehistoric human populations, technologies played a fundamental role in the acquisition of different resources and are represented in the main daily living activities, such as with bone, wooden, and stone-tipped spears for hunting, and chipped-stone tools for butchering. Considering that paleoanthropologists and archeologists are focused on the study of different processes involved in the evolution of human behavior, investigating how hominins acted in the past through the study of evidence on archeological artifacts is crucial. Thus, investigat ing tool use is of major importance for a comprehensive understanding of all processes that characterize human choices of raw materials, techniques, and tool types. Many functional assumptions of tool use have been based on tool design and morphology according to archeologists’ interpretations and ethnographic observations. Such assumptions are used as baselines when inferring human behavior and have driven an improvement in the methods and techniques employed in functional studies over the past few decades. Here, while arguing that use-wear analysis is a key discipline to assess past hominin tool use and to interpret the organization and variability of artifact types in the archeological record, we aim to review and discuss the current state-of-the-art methods, protocols, and their limitations. In doing so, our discussion focuses on three main topics: (1) the need for fundamental improvements by adopting established methods and techniques from similar research fields, (2) the need to implement and combine different levels of experimentation, and (3) the crucial need to establish standards and protocols in order to improve data quality, standard ization, repeatability, and reproducibility. By adopting this perspective, we believe that studies will increase the reliability and applicability of use-wear methods on tool function. The need for a holistic approach that combines not only use-wear traces but also tool technology, design, curation, durability, and efficiency is also debated and revised. Such a revision is a crucial step if archeologists want to build major inferences on human decision making behavior and biocultural evolution processes.
- Why should traceology learn from dental microwear, and vice-versa?Publication . Calandra, Ivan; Pedergnana, Antonella; Gneisinger, Walter; Marreiros, JoaoDental and artifact microwear analyses have a lot in common regarding the questions they address, their developmental history and their issues. However, few paleontologists and archeologists are aware of this, and even those who are, do not take into account most of the methodological insights from the other field. In this focus article, we briefly review the main developmental steps of both methods, highlight how similar their histories are and how combining methodological developments can improve both research fields. In both cases, the traditional analyses have been strongly criticized mainly because of their subjectivity and their lack of repeatability and reproducibility. Quantitative surface texture analyses have been proposed in response, resulting in dental microwear texture analysis (DMTA) and quantitative artifact microwear analysis (QAMA). DMTA is however a more mature method than QAMA and is well supported within the paleontological community. In this paper, focused on the methodological framework of both fields, we address this topic by arguing that traceologists could borrow a lot from DMTA; this would allow QAMA to become an established method much more quickly. Dental microwear analysts can also learn from traceology, especially regarding sample preparation, experimentation and residue analysis. We hope that this focus article will stimulate more awareness, exchange and collaboration between paleontologists and archeologists, and especially between dental and artifact microwear analysts. Paleontology, archeology and the field of surface analysis as a whole would all benefit from such cooperation.
- A ‘family of wear’: traceological patterns on pebbles used for burnishing pots and processing other plastic mineral mattersPublication . Dubreuil, Laure; Robitaille, Jérôme; Gonzalez-Urquijo, Jesús; Marreiros, Joao; Stroulia, AnnaThe development of technologies related to plastic mineral matters (PMM), including clay, mud, and plaster, represents a major step in cultural evolution because of their important repercussions for food processing, storage, transportation, construction, and symbolic expression in past human societies. This paper aims to illuminate the chaines operatoires employed in the transformation of PMM and highlight early evidence for these technologies in the archaeological record. Our focus is 'ad-hoc' (or non-manufactured) ground stone tools used in finishing operations. Specifically, we discuss pebbles and cobbles employed to regularize, smooth, or burnish clay and mud-based products. Because these tools consist of unmodified rocks, recognizing and understanding the traces developed through use is essential for their identification. This is a pilot study that draws on experiments, ethnographic studies and quantification via confocal microscopy to assess the variability of use-wear developed on mud and clay processors. Extra attention is placed on micro-polish, not only because this type of wear has been seldom described before for such tools, but also because it appears to be highly diagnostic. We suggest that the variability observed can be described as a family of wear, that is, a range of recurrent use-wear characteristics associated with the processing of PMM. We analyze two collections associated with different chrono-cultural contexts: the Late Natufian site of Hilazon Tachtit in the Southern Levant and the Late Neolithic site of Kremasti-Kilada in Greece. At both sites, the identification of processors of PMM provides pivotal data to understand the relevant chaines operatoires, assess the emergence and development of these technologies, and also explore symbolic behaviors.
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