Journal of Lithic Studies
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Bolas, projectile points and hunting technologies in Southern Patagonia (Santa Cruz, Argentina) during the Late Holocene
Full text linkThe late Holocene in the central-western region of the Santa Cruz province (Southern Patagonia, Argentina) was characterized by the occurrence of climatic and environmental change processes which implied a progressive drought, markedly recorded after ca. 3000 years BP. Peopling processes in the region during this period implied mobility strategies that included residential mobility in lowlands combined with logistical mobility in highlands. In this changing context, local hunter-gatherer groups used a variety of weapons for obtaining prey: bolas, bow and arrow and spears or darts.
In this context, this work analyses the distribution and chronology of the lithic components of these technologies (arrow and spear/dart stone points and stone balls) including evidence of their manufacture (preforms and raw materials). For this, we consider different environments (different low basins and high basins and plateaus) and different types of sites (open air site, basaltic wall, rock shelter, hunting blind and burial). The aim is to assess the role of these technologies in the context of changes in mobility strategies and landscape use. The evidence collected suggests that these three technologies had important differences in their use and production, especially in their replacement potential, manufacturing possibilities, transport and repair. These differences possibly made them complementary. Our main argument suggests that hunter-gatherers diversified technologies, specifically those used to obtain prey, in a context of landscape and resource fragmentation. Therefore, there was a complementary but differential use of technologies and not a process of adoption and abandonment. New technical options were incorporated into previously established ones, thus offering greater flexibility to the subsistence system
Gender Prehistory: Shaping Techniques applied to Osseous Artefacts
No full textScraping and abrasion are quite ancient and universal techniques. On bone, antler, and teeth, these two techniques can sometimes be used for the reduction sequence but mainly serve for shaping, even though chronological, cultural, and geographical gradients can be observed. In some archaeological assemblages, during the European Neolithic for example, abrasion dominates whatever the type of object manufactured. In contrast, in the Arctic Pre-Inuit and Inuit contexts scraping largely predominates. Our goal is to question the variations from an almost complete exclusivity for only one technical practice to a mix of both. In particular, could the sexual division of labour influence both the technical and social spheres of activity? Why for a given type of artifact is a clear choice sometimes made for only one technique when both scraping and abrading are encountered within a single assemblage? To address these questions, we compared data obtained from different socio-economic and environmental contexts. The techniques used to produce osseous and lithic tools by Neolithic and Epipaleolithic groups from Europe, Near East and Maghreb have been analyzed and compared to those encountered in the American Arctic societies. Ethnographical comparisons help in analyzing potential links between techniques, lifestyles and gender. High-mobility, hunter-gatherer subsistence and scraping seem to be in association and opposed to sedentary, farming, milling, women activity and abrasion.L’abrasion et le raclage sont des techniques banales, très anciennes et universelles, mises en œuvre pour le travail des matières osseuses dès le Paléolithique moyen. Elles sont le plus souvent associées à l’étape de façonnage des objets, en terme opératoires, mais aussi, dans certains cas appliquées au débitage. Quand ces deux techniques se trouvent utilisées conjointement par les artisans, leur proportion varie en fonction de gradients chronologiques, culturels mais aussi géographiques. Ainsi, dans le Vieux monde, à partir du Pre-Pottery Neolithic B moyen au Proche-Orient (PPNB moyen, fin du IXe millénaire) (Aurenche 2010), au Néolithique ancien européen (fin du VIIe / début du VIe millénaires), et, dans une moindre mesure au Maghreb oriental (VIIe / VIe millénaire), l’abrasion est majoritairement employée pour le façonnage des objets, quels que soient leur type. Le raclage est plus régulièrement appliqué à l’entretien des outils et à leur raffûtage, au cours de leur utilisation. A l’opposé du Néolithique, dans le contexte arctique du Nouveau monde, le raclage prédomine très largement ; l’abrasion n’est utilisée que de façon exceptionnelle, pour obtenir une surface plane, renforcer le bord d’un tranchant ou pour la confection d’objets à valeur symbolique.
Quelles sont les raisons pour lesquelles les proportions de ces deux techniques varient pour aller jusqu\u27à une quasi-exclusivité pour l’une ou l’autre pratique selon les contextes ? Une division genrée du travail, différente selon les cultures, peut-elle rendre copte d’un lien entre sphères technique et sociale ? Pour traiter ces questions, nous avons comparé les données provenant de contextes socio-économiques et environnementaux différents.
Les résultats issus de la comparaison conduisent à proposer un lien entre techniques, mobilité et genre des individus. Ainsi, les sociétés arctiques se caractérisent par une forte mobilité et une répartition genrée des productions : les matières souples sont travaillées par les femmes, alors les matières dures le sont par les hommes. Les deux groupes partagent cependant un même registre de techniques, ce qui permet, au besoin, de toujours suppléer à l’absence de l’un ou l’autre genre. Les matières osseuses, travaillées par les hommes, font l’objet d’un traitement spécifique, distinct de celui des autres matériaux tels que le bois végétal ou la pierre, avec un façonnage quasi-exclusif effectué par raclage. A l’inverse, dans le Néolithique, et ce depuis le Pre-Pottery Neolithic B moyen (PPNB moyen), la sédentarité et le développement des activités de mouture ont probablement bouleversé la répartition du travail entre hommes et femmes, et accessoirement l’usage des techniques. La fabrication de nombreux objets en matière osseuse employé au quotidien y serait associée aux activités féminines, travail des peaux et des végétaux souples, et attachées à la sphère domestique, dans ou à proximité immédiate de la maison. Le raclage est plus fréquemment employé pour le raffûtage des outils pointus. Nous proposons d’y voir l’expression de différences de lieux entre la fabrication (domestique) et l’usage (hors du contexte domestique) des outils. De même, à l’échelle culturelle, nous soutenons l’idée de l’emploi du raclage versus abrasion, comme l’expression de sociétés mobiles, associées à un mode de vie nomade, versus sociétés sédentaires, associées à l’agriculture. Ainsi, malgré des conditions environnementales et climatiques imposant parfois des adaptations techniques, ce transfert ne s’est cependant pas opéré en contexte arctique où les artisans, toujours mobiles, ont parfois préféré substituer le raclage à la perforation plutôt qu’employer l’abrasion. De même, l’abrasion étant employée dans la fabrication et le maintien des outils, et par analogie de la gestuelle de l’abrasion et des activités de mouture ou de broyage, le développement et la prédominance de l’abrasion, au Néolithique, pourrait ressortir de la féminité. C’est en tout cas une hypothèse que l’on peut poser et travailler à l’avenir.
 
The new digital archive at the Neanderthal Museum
Full text linkThe management and publication of digital data on online repositories constitutes a task that is becoming more and more relevant for museums and cultural heritage institutions alike. Not only is it important to archive the growing volume of data produced on a daily basis, but also to make this data available and reach out to old and new audience targets, such as fellow researchers, students, enthusiasts, in new and meaningful ways. The Neanderthal Museum, since two decades engaged in the development and establishment of a diversified digital offer, profiting from the recent completion of the DISAPALE project and its hundreds of newly scanned 3D models, has created a brand new online portal, planned as the core of its digital activity. The history of development (specifically the NESPOS portal), the issues encountered in the planning and realization phases (e.g. requirements for efficiency and long-term maintainability, freedom from previous dependencies on proprietary software), as well as the design decisions and technical solutions are critically discussed, highlighting strengths, weaknesses and possible future improvements. An introduction to the client-server architecture is provided, detailing the development of the back-end using a lightweight Java server component with integrated PostgreSQL relational database and the user-facing front-end built with modern web technologies to create a tailor-made, flexible and clutter-free web application. Finally a short look at the current status of scientific enterprises in digital archaeology is given, with a specific focus on the entanglements between museums, cultural heritage institutions and government entities
Singularidades tecno-culturais na região sudoeste do Planalto Central brasileiro no Holoceno Inicial
No full textThis article aims to contribute to expanding knowledge about the panoply of lithic tools present in Early Holocene archaeological sites located in the Brazilian Central Plateau. These sites have traditionally been interpreted within the context of the Itaparica tradition, whose artifacts called "slugs" or "plano-convex" were used as cultural markers. Technological research over the last twenty years on lithic materials from sites typologically attributed to the Itaparica tradition has allowed a better definition of what came to be called the Itaparica techno-complex. Due to the spectacular nature of the “plano-convex” objects identified in these ancient contexts, other artifacts are usually overlooked in research. Our proposal was, therefore, to look in more detail at the subtle incisive tools that are associated (or not) with “plano-convex” artifactual structures in the collections of two sites from the southwest region of the Central Plateau: the GO-JA-01 site (Diogo Lemes), dated from 12717 - 12143 cal. (Beta-3699), and the site MT-SL-31 (Morro da Janela), dated from 11994 - 11316 cal (Beta-78053). We could see that they are, very often, structured on other technical production principles and associated with specific operational schemes.
We based our research on the Techno-functional Approach. This approach allows us to identify the coherences that are established within a volumetric structure (a specimen) in terms of its structuring subsets -minimally, the transformative edge(s) and the possible prehensive unit(s) - in light of their functional potential. Furthermore, it allows us to think about the technical meaning of artefactual structures by reinserting them into the set of which they are part (a population), providing data on the techno-functional consistency of the collections. In methodological terms, the identification of the operational schemes was carried out based on the diacritical analysis of the negatives present in the artifact, with the production modes being highlighted based on the technical principles of affordance, debitage and shaping.
We were able to group the sharp tools from these collections into five techno-functional categories: unifacial shaped tools from normalized blanks (limaces); unifacial shaped tools on regularized blanks; tools shaped on blanks of cobble; tools with restricted modification; regularized and non-regularized blanks. We were also able to identify in the collections the representative occurrence of unexhausted cores with the presence of small negatives, which led us to infer the production of even smaller blanks which, however, were not detected in the collection. Furthermore, we identified the presence of discoid D-type debitage related to some of the tools. These technological details obtained with the investigation of the aforementioned archaeological sites of the Central Plateau, when considered in the light of spatial, chronological and paleoenvironmental information, allow us to consider the scenarios concerning the population dynamics of that period. The tools categories evidenced in this paper, added to the techno-cultural particularities found in other Central Plateau sites and expands the Itaparica toolbox. They bring about a greater understanding of the Techno-cultural diversity of the technical memories of the human groups that occupied the extensive area of the Central Plateau, enabling further investigations into the connections of technical knowledge between regions.Este artigo visa contribuir para a ampliação do conhecimento sobre as panóplias de ferramentas líticas presentes em sítios arqueológicos do Holoceno Inferior localizados no Planalto Central brasileiro. Esses sítios têm sido tradicionalmente interpretados dentro do contexto da Tradição Itaparica, cujos artefatos denominados de "lesmas" ou "plano-convexos" foram identificados como marcadores culturais. Os avanços nas pesquisas nos últimos vinte anos sobre as características técnicas, tecnológicas e tecno-funcionais de materiais líticos tipologicamente atribuídos à Tradição Itaparica permitiram uma melhor definição daquele que veio a ser denominado de complexo tecno-cultural Itaparica Lourdeau (2010:59). A partir da coleção lítica de dois sítios, pesquisados inicialmente por Oliveira (2014) e Oliveira (2019), provenientes da região sudoeste do Planalto Central, o sítio GO-JA-01 (Diogo Lemes), com datação mais antiga de 12.717 - 12.143 cal. (Beta-3699), e o sítio MT-SL-31 (Morro da Janela), de 11.994 - 11.316 cal (Beta-78053), buscamos criar condições heurísticas para que desses contextos antigos pudessem emergir um aporte de expressões culturais de baixa visibilidade técnica. Tais expressões são usualmente preteridas por estarem associadas a materiais cuja estrutura artefatual é caracterizada pela alta normalização e/ou pela padronização. Objetivamos, assim, olharmos com mais detalhamento para as ferramentas incisivas sutis que estão associadas às estruturas artefatuais “plano-convexas”.
Nossa pesquisa fundamentou-se na abordagem Tecno-funcional (Boëda 2013:39), a qual permite identificar as coerências que se estabelecem no interior de uma estrutura volumétrica (um espécimen) nos termos de seus subconjuntos estruturantes - minimamente, o(s) gume(s) transformativo(s) e a(s) unidade(s) preensiva(s) - à luz de seu potencial funcional. Ademais, ela permite pensar o sentido técnico das estruturas artefatuais ao reinseri-las no conjunto do qual fazem parte (uma população), fornecendo dados sobre a consistência tecno-funcional das coleções. Em termos metodológicos, a identificação dos esquemas operatórios foi realizada a partir da análise diacrítica dos negativos presentes nos artefatos e dos modos de produção evidenciados com base nos princípios técnicos de afordância, debitage e façonagem.
O ordenamento estrutural entre as porções transformativas e possíveis porções preensivas, nos possibilitou agrupar as seguintes categorias tecno-funcionais:
1) “Instrumentos com façonagem unifacial a partir de suportes normalizados (limaces)” - apresentam estrutura técnica estável, caracterizada por um suporte alongado e volumoso em uma de suas faces. A simetria das laterais e o plano de seção foram obtidos por façonagem, o(s) gume(s) delineados por confecção e podem compor de uma ou mais unidades transformativas. Algumas peças são altamente normalizadas apresentando recorrentemente uma unidade tecno-transformativa, localizada na porção apical. Outras são menos normalizadas, sua estrutura funciona como um suporte onde se instalam mais de uma unidade transformativa. São peças de arenito silicificado e sílex.
2) “Instrumentos com façonagem unifacial com suportes regularizados" - o suporte não é normalizado, os perfis e as laterais são assimétricos. Os princípios da afordância, façonagem e debitage atuaram na estrutura da ferramenta, podendo compor uma ou duas unidades transformativas. São peças de arenito silicificado, quartzito e sílex,
3) “Instrumentos produzidos sobre suportes de seixos” - os seixos foram selecionados por critérios técnicos de afordância, seguidos de façonagem e confecção de gumes, em contornos diversos. São peças de arenito silicificado e quartzito.
4) Instrumentos com modificação restrita” - foram identificados três tipos de estruturas de suportes: algumas pouco regularizadas, provenientes da debitagem tipo C; outras normalizadas, provenientes da debitagem tipo D-discöide; e ainda as de "cadeias operacionais ramificadas" (Bourguignon et al. 2004), derivadas de lascas de façonagem. Os gumes são definidos por retoques ou traços de uso. São peças de arenito silicificado, sílex, basalto e quartzo.
Também pudemos identificar na coleção a ocorrência representativa de núcleos pequenos, não esgotados com presença de negativos de pequenas dimensões, o que nos levou a inferir a possibilidade de produção de suportes ainda menores, contudo, estes não foram detectados na coleção.
Compreendemos que a onipresença dos instrumentos comumente denominados de limaces, presentes na maioria dos sítios do Planalto Central, nos leva a considerar o compartilhamento da estrutura técnica dessa ferramenta, entre diferentes grupos humanos ao longo de pelo menos 4.000 anos. A proposição sobre a dispersão e possíveis conexões desta cultura técnica está mais alinhada com uma perspectiva interativa do que com uma convergência técnica (Chevrier 2012). A variabilidade técnico-funcional dessas peças está associada à temporalidades distintas, isto reforça a ideia de movimento e potencial de mudança nas tradições culturais (Sahlins 1997).
Também destacamos a presença marcante do princípio da afordância (Boëda & Ramos 2017) entre as ferramentas do sítio MT-SL-31, possibilitando a supressão da fase de debitagem. Compreendemos que isso não encurta o tempo da cadeia operatória, neste caso o maior investimento estaria no critério técnico de seleção dos suportes (seixos) visando produzir a futura ferramenta. Neste movimento, entendemos que as categorias natural e cultural são complementares. Desvelam também o enredamento dos grupos humanos com suas cercanias, fazendo-nos considerar não apenas o sítio, mas também o entorno como participantes do projeto cultural.
Os instrumentos de baixa visibilidade foram caracterizados, não necessariamente pelas suas dimensões reduzidas, mas principalmente por sua estrutura técnica ter sido pouco modificada, tornando-as ferramentas de difícil identificação se utilizarmos somente o critério “forma”, sem o desenvolvimento de análises tecnológicas. Incorporar e elevar essa categoria tecnográfica ao contexto da presente discussão, as emparelhando às demais presentes no tecno-complexo de Itaparica, significa dar visibilidade a um conjunto de objetos ainda pouco considerados nas análises tecnológicas da região sudoeste do Planalto Central. Isto, por sua vez, instiga os estudos a irem além do \u27formal\u27, do normalizado, seguindo o desafio da arqueologia aplicada ao tempo profundo em termos de se afastar do preconceito que equipara uma maior quantidade de negativos a um maior nível de complexidade tecnológica complexity (Maigrot & Plisson 2006).
As minúcias tecnológicas obtidas com a investigação dos sítios arqueológicos supramencionados, quando consideradas à luz de informações espaciais, cronológicas e paleoambientais, permitem ponderar sobre os cenários concernentes às dinâmicas populacionais desse período. As categorias de ferramentas evidenciadas neste artigo, somadas às particularidades tecno-culturais encontradas em outros locais do Planalto Central, ampliam o conjunto de ferramentas de Itaparica. Proporcionam uma maior compreensão da diversidade técnico-cultural das memórias técnicas dos povos que habitaram a extensa área do Planalto Central brasileiro, possibilitando investigações mais aprofundadas sobre as conexões entre os conhecimentos técnicos presentes em diferentes regiões da América do Sul
Mapping procurement areas of lithic resources and mobility patterns: A GIS-based approach to the early colonization of Western Mediterranean islands
Full text linkIs it possible to define based on the circulation of chert and obsidian the patterns of mobility and the procurement strategies of lithic resources among the first inhabitants of the Western Mediterranean islands of Corsica and Sardinia?
This paper tackles this question through the following research objectives: 1) To build, through bibliographic research, a systematic database including all published data concerning the presence of chert and obsidian artefacts in Sardinian-Corsican sites dated to the Pre-Neolithic and the Early Neolithic; 2) To create a specific cartography on the geographical distribution of these lithotypes across the two studied islands. Data have been geo-referenced with the QGIS 3.20 open-source software, both to make them visible on the map and to introduce the fundamental variables of space-territory into the research; and 3) To define mobility patterns for the supply of chert and obsidian based on the available results of provenance analyses, using QGIS to draw the movement lines from the findspot to the source with the principle of the minimum effort: that is, through the development of a Least Cost Path Analysis (LCPA). This is to say that the tracing of the probable routes followed by humans will be based on the calculation of the shortest distances from the raw material sources to their findspots based on orography and topographic variables.
The results on the procurement areas and mobility patterns to perform specific tasks, as lithic procurement, will contribute to the debate on resource management and landscape knowledge of early human groups colonizing insular environments
Experimental bone toolmaking: A proposal of technological analytical principles to knapped bones
Full text linkSince the origins of technology, human groups have used a wide variety of lithic and organic raw materials to make tools. In particular, bone was used as raw material for creating knapped artefacts. Nevertheless, the recognition of these technological elements in the archaeological record has generated some debate, since modern taphonomy has shown that certain non-anthropic agents create modifications that can mimic knapped bone tools. For this reason, the criteria for identifying archaeological bone tools and pseudo-tools have still not been clearly defined.
As a contribution to this subject, here we present the results of an experimental programme of intentional anthropic marrow fracturing of fresh and semi-fresh bovine long bones. After marrow removal, some of the diaphyseal fragments obtained were selected to be used directly as tools, while others were slightly retouched. The aim was to describe the bone toolmaking process and the simple and retouched tools obtained experimentally according to technological criteria. The technological analysis approach was based on an adaptation of the Logical Analytical System (LAS), which uses structural categories within an operative chain rather than techno-typological features. LAS has been widely used to analyse Pleistocene lithic assemblages and is here applied for the first time to the study of bone industry.
The results allow us to present new analytical criteria with which to describe simple and retouched bone tools from a holistic perspective, combining technological and taphonomic terminology. Our intention is to improve the criteria for differentiating intentional retouching in bone tools from other modifications to bone remains generated by non-anthropic agents. The final goal of this study is to further the interdisciplinary study of minimally modified bone tools, proposing a technological method for studying knapped bone tools
What lies in between: Levallois, discoid and intermediate methods
Full text linkLithic artefacts are usually associated with the different knapping methods used in their production. Flakes exhibit metric and technological features representative of the flaking method used to detach them. However, lithic production is a dynamic process in which discrete methods can be blurred, and in which features can vary throughout the process. An intermediate knapping method between the discoid and Levallois is commonly referred to under an umbrella of terms (the present research uses the term hierarchical discoid), and is associated with a broad geographical and chronological distribution throughout the Early and Middle Palaeolithic. This intermediate knapping strategy exhibits features of both the discoid and Levallois knapping methods, raising the question of the extent to which flakes from the three knapping methods can be differentiated and, when one is mistaken for another, the direction of confusion. An experimental assemblage of flakes detached by means of the three methods was used along with an attribute analysis and machine learning models in an effort to identify the knapping methods employed. In general, our results were able to very effectively differentiate between the three knapping methods when a support vector machine with polynomial kernel was used. Our results also underscored the singularity of flakes detached by means of Levallois reduction sequences, which yielded outstanding identification values, and were rarely erroneously attributed to either of the other two knapping methods studied. Mistaking the products of the discoid and hierarchical discoid methods was the most common direction of confusion, although a good identification value was achieved for discoid flakes and an acceptable value for hierarchical discoid flakes. This shows the potential applicability of machine learning models in combination with attribute analysis for the identification of these knapping methods among flakes
Estableciendo un nuevo flujo de trabajo en el estudio de la distribución de la reducción en núcleos
No full textNew methodological approaches focused on studying the reduction and use-life of stone tools have emerged in recent years, enabling researchers to move beyond strict technical and technological characterizations and explore specific aspects of occupation dynamics and economic management of resources. Previous studies have shown the importance of reduction distributions of individual measurements rather than averaged values. In this sense, survival analysis, and more specifically Weibull distributions, are one of the main inferential tools used in reduction studies. However, the resolution of Weibull distribution obtained from different methods has not been tested experimentally. In this paper, we present an evaluation of some of the main methods used in the study of core reduction intensity, such as the Volumetric Reconstruction Method, the Scar Density Index, and the non-cortical surface percentage. Our results show 1) strong and positive correlations between these approaches and actual reduction intensity, 2) similar Weibull distributions for non-cortical surface percentage, Volumetric Reconstruction Method, and logarithmic transformation of Scar Density Index. In addition, 3) the results from each method show a similar intra-assemblage variation, with a high percentage of agreement between them.
As a result, all the evaluated proposals are useful and reliable methods for estimating the degree of reduction. Finally, a workflow is proposed for approaching reduction in archaeological assemblages by integrating different methods in the same study.La proliferación de enfoques orientados al estudio de la vida de uso o reducción de los útiles líticos en las últimas décadas ha permitido profundizar en aspectos del comportamiento humano más allá de la propia estructura tecnológica, relacionados con la dinámica de ocupación y la gestión económica de los recursos líticos. No obstante, estudios previos en este campo han mostrado una mayor capacidad inferencial de las distribuciones de la intensidad de reducción de los conjuntos sobre valores promediados. En este sentido, el análisis de supervivencia y, más concretamente, las distribuciones Weibull, son una de las principales herramientas inferenciales utilizadas en los estudios de intensidad de reducción. Sin embargo, hasta la fecha no se ha comprobado experimentalmente la resolución de las curvas Weibull obtenidas a partir de diferentes métodos.
En este trabajo, presentamos una evaluación del potencial inferencial de algunos de los principales métodos utilizados en el estudio de la intensidad de reducción en núcleos, como el Volumetric Reconstruction Method, el Scar Density Index y el porcentaje de superficie no cortical. Por primera vez, esta exploración se ha llevado a cabo desde una doble perspectiva: comparando la resolución de las curvas de distribución de Weibull obtenidas por cada método y estudiando la variabilidad intra-conjunto de la reducción a nivel individual mediante análisis multivariantes que combinan los diferentes índices de reducción.
Los materiales utilizados en este trabajo son los mismos núcleos experimentales realizados en trabajos previos (Lombao et al. 2020). El conjunto experimental está compuesto por 64 cantos fluviales recogidos de las terrazas del río Arlanzón (Burgos, España) y en cuyo experimento han participado cuatro talladores diferentes siguiendo cuatro estrategias de talla diferentes: unipolar unifacial, multipolar bifacial centrípeto, multipolar multifacial y bifaces.
Los resultados obtenidos demuestran una fuerte correlación positiva entre estos enfoques y la intensidad de reducción real. Además, se encontraron distribuciones Weibull similares para el porcentaje de superficie no cortical y el Volumetric Reconstruction Method. Sin embargo, en el caso del Scar Density Index, para obtener distribuciones similares a las distribuciones reales, ha sido necesario en primer lugar la transformación logarítmica del Scar Density Index y la normalización min-max de los datos. Los resultados también indican una variación intra-conjunto similar y un alto porcentaje de concordancia entre las diferentes aproximaciones empleadas. Todo ello indica que todas las propuestas aquí evaluadas son métodos útiles y estadísticamente fiables para estimar el grado de reducción en núcleos.
Además, para evaluar la sensibilidad de las curvas de distribución de Weibull, hemos submuestreado aleatoriamente el conjunto experimental a intervalos de cada 10%, lo que nos ha permitido observar la evolución de los parámetros Shape y Scale de las distribuciones Weibull tanto de los datos reales como de los distintos índices a medida que se transforma el conjunto.
Los resultados muestran que no hay grandes variaciones en los valores de Shape y Scale de los datos reales de reducción a medida que disminuye el porcentaje de núcleos en el conjunto. Sin embargo, los métodos responden de forma diferente a estos cambios en el conjunto experimental. Así el porcentaje de superficie no cortical y el Volumetric Reconstruction Method permanecen estables a lo largo de las simulaciones. Sin embargo, la normalización min-max de la transformación logarítmica del Scar Density Index muestra mayores oscilaciones en el caso del valor Shape, mientras que el valor Scale es más estable.
Finalmente, se propone un flujo de trabajo para abordar el estudio de la intensidad de reducción en conjuntos arqueológicos integrando diferentes métodos en un mismo estudio. Además, el uso del Análisis de Componentes Principales para combinar índices proporciona una nueva visión de la variabilidad interna de los conjuntos, permitiendo una evaluación más precisa del grado de reducción de cada núcleo
Tecnología de parapetos: un estudio de los conjuntos líticos en estructuras de piedra del Holoceno tardío en Patagonia (Argentina)
No full textStone structures called parapetos are a highlighted feature of the archaeological record in central-western Santa Cruz, Patagonia. More than 500 have been registered so far with varied sizes and shapes and clustered in different amounts. They are located in basaltic plateaus, over 700 masl. These hunter-gatherer structures are believed to be mainly related to hunting activities though some sites have revealed a more general function. Radiocarbon dates reveal that they are a typical Late Holocene technology.
This work discusses the characteristics of lithic materials recovered in these particular sites with a specific spatial and temporal distribution in Patagonia. We evaluate the existence of variability in lithic artefacts related to stone structures recovered in different areas: Pampa del Asador (Cerro Pampa), Guitarra Plateau, Asador Plateau and the Strobel Plateau. Diverse types of hunting blind sites have been included: isolated structures and grouped ones located in different topographic and ecological contexts. Materials were recovered from inner and outer surfaces of structures as well as from stratigraphic contexts. The sample includes tools, debitage and cores; more than 10000 lithic artefacts are included.
Results show that there are similarities in the characteristics of artefacts discarded in parapetos from different areas. However, variability in the type and characteristics of artefacts in each assemblage could account for a wider array of activities being carried out in parapetos from the northern sector of the region under study. Thus, strategies for occupying highlands during the Late Holocene differed.
The evidence discussed summarises more than 20 years of on-going investigations in the region. It provides exceptional information based on systematic analysis of a significant sample of lithic artefacts in hunting blinds.Las estructuras de piedra denominadas parapetos son un rasgo prominente del registro arqueológico del centro-oeste de Santa Cruz, Patagonia (Argentina). Se trata de construcciones antrópicas formadas por la acumulación de rocas inmediatamente disponibles sin argamasa formando una pequeña pared que ofrece reparo contra los vientos predominantes. Más de 500 de estas estructuras han sido registradas hasta el momento en el campo en la región bajo estudio. Si bien la técnica constructiva es la misma, se observan en variados tamaños y formas y pueden hallarse tanto aisladas como agrupadas en diferentes cantidades. Se localizan casi de manera exclusiva en mesetas basálticas y sectores altos de la región, por arriba de los 700 msnm. Estas estructuras de los cazadores-recolectores se asocian principalmente a actividades cinegéticas, aunque algunos sitios evidencian funciones más generalizadas. Las dataciones radiocarbónicas indican que se trata de una tecnología propia del Holoceno tardío con fechados posteriores a los 2000 años AP y su uso se vincula principalmente a la ocupación logística y/o estacional de los sectores altos por parte de los grupos humanos que habitaban la región en el pasado.
Este trabajo discute las características de los materiales líticos recuperados en estos sitios cuya distribución temporal y espacial es tan particular en Patagonia. Evaluamos la existencia de variabilidad en los artefactos líticos hallados en asociación a estructuras de piedra presentes en diferentes áreas ubicadas en la región bajo estudio: Pampa del Asador (Cerro Pampa) y las mesetas del Guitarra, Asador y Strobel. Diversos tipos de sitios de parapetos fueron incluidos para lo cual se tomaron en cuenta tanto estructuras aisladas, como agrupadas, así como localizadas en diferentes contextos topográficos y ecológicos. Los materiales líticos analizados fueron recuperados tanto de las superficies interiores como exteriores de las estructuras y se incluyen, además, materiales provenientes de estratigrafía. La muestra se compone de instrumentos, desechos de talla y núcleos en variadas materias primas, lo que suma más de 10000 artefactos analizados.
Los resultados obtenidos permiten destacar que hay similitudes en las características de los artefactos descartados en los parapetos de diferentes áreas. Un aspecto a resaltar se vincula al uso de las materias primas, donde la obsidiana negra, proveniente de Pampa del Asador, es el recurso lítico más destacado en casi todas las áreas. Sin embargo, se observa variabilidad en la estructura artefactual de algunos parapetos, especialmente de aquellos ubicados en el sector norte de la región bajo estudio. Esto podría dar cuenta de un mayor rango de actividades llevado a cabo en las estructuras localizadas en dicho sector. Tomando esto en consideración, se evalúan y discuten las diferencias en las estrategias de ocupación de las mesetas y sectores altos durante el Holoceno tardío.
La evidencia presentada en este trabajo sintetiza más de 20 años de investigaciones en la región donde sistemáticamente se han relevado y estudiado dichas estructuras de piedra, así como la evidencia asociada a éstas. En este sentido, los resultados y discusión proveen información excepcional basada en un análisis detallado de una muestra significativa de artefactos líticos hallados en parapetos, sitios característicos de la región bajo estudio
Techno-economy of lithic raw materials in Piedmont (north-western Italy): A first life-like scenario
Full text linkData about Palaeolithic peopling, settlement dynamics and techno-economy of the south-western margin of the Alpine region are sketchy. In this area, the lack of systematic research and the scarcity of lithic raw materials, spread the idea that Piedmont was not inhabited during Palaeolithic. In 2009, the re-starting of the excavations at the Ciota Ciara cave, gave rise to new questions and to the development of research projects at a regional scale.
The Ciota Ciara cave is the only Middle Palaeolithic site object of multidisciplinary and systematic investigations. Its lithic assemblage, analysed through a techno-economic approach, allows to understand in detail the technological choices and the land mobility of the Neanderthal groups on a local and sub-regional scale. Other Middle Palaeolithic assemblages are known in the region and are all issued from surface collections. They come from the northern part of the region, from Vaude Canavesane, Trino, Baragge biellesi and Colline Novaresi. The technological study of these assemblages led to the identification of strong similarities in the technological choices of the Middle Palaeolithic human groups: they based their technology on the exploitation of vein quartz, a rock diffused all over the regional territory, from time to time accompanied by other local (spongolite, rhyolite, metamorphic rocks, jasper) and allochthonous (radiolarite and flint) lithic resources, with technological adaptation to their quality and mechanical properties both when it comes to predetermined methods (Levallois and discoid) and when expedient reduction sequences are used. Concerning Upper Palaeolithic, the only lithic assemblage issued from an archaeological excavation (and therefore with a clear stratigraphic context) is that from the Epigravettian site of Castelletto Ticino. Other lithic artefacts referable on a techno-typological basis to Upper Palaeolithic are from Trino and Colline Novaresi. As for Middle Palaeolithic, the techno-economic approach used in the analysis of these lithic assemblages, allow to have, for the first time, reliable data at a regional scale.
In this work we present the data obtained after about ten years of research in Piedmont: they outline a scenario where, even in the limits of analysis mostly based on materials issued from surface collections, we can see both clear differences between the Middle and the Upper Palaeolithic technological behaviours and hypothesise the land mobility of the hunter-gatherers’ groups that inhabited the region