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- As indústrias do Paleolítico inferior e médio associadas ao terraço T4 do Baixo Tejo (Portugal central); arquivos da mais antiga ocupação humana no oeste da Ibéria, com ca. 340 ka a 155 kaPublication . Cunha, Pedro P.; Cura, Sara; Cunha Ribeiro, Joao Pedro; Figueiredo, Silverio; Martins, Antonio A.; Raposo, Luis; Pereira, Telmo; Almeida, NelsonAtravés dos registos geomorfológicos e sedimentares, os rios fornecem relevantes arquivos de mudanças paleoambientais, nomeadamente paleoclimáticas e paleogeográficas. As sucessões sedimentares melhor datadas são as mais importantes, com as idades numéricas dos respetivos dos eventos sedimentares, de fósseis e de materiais arqueológicos, obtidas por uma variedade de técnicas. Os arquivos fluviais do Quaternário fornecidos pelo rio Tejo em Portugal (Baixo Tejo) constituem um importante repositório de dados para estudos da evolução da dinâmica sedimentar e da paisagem, bem como da ocupação humana pré-histórica. O atual estado de conhecimentos resultantes das sucessivas abordagens usando métodos da geomorfologia, litostratigrafia, arqueologia e datação numérica no estudo do Terraço T4 do Baixo Tejo é aqui sintetizado. Este trabalho tem enfoque nos sítios com indústrias do Paleolítico que foram encontradas no Terraço T4, o qual é constituído por uma unidade basal de cascalheiras e uma unidade superior dominada por areias. Os mais antigos artefactos são de rara ocorrência e foram encontrados na unidade de Cascalheiras Inferiores, apresentando formas bifaciais pouco elaboradas que podem ser atribuídas ao Acheulense, com uma idade provável de ca. 340 a 325 ka. Em contraste, os níveis estratigráficos inferiores e médios da unidade de Areias Superiores do T4 apresentam vários sítios arqueológicos que documentam fases sucessivas de um Acheulense evoluído, que foram datados de ca. 325 a 220 ka. Nos níveis estratigráficos dos depósitos do topo do T4 foram encontradas indústrias do Paleolítico Médio e datam, provavelmente, de ca. 165 a 155 ka.
- The lowermost Tejo River terrace at Foz do Enxarrique, Portugal: a palaeoenvironmental archive from c. 60–35 ka and its implications for the Last Neanderthals in Westernmost IberiaPublication . Cunha, Pedro; Martins, António; Buylaert, Jan-Pieter; Murray, Andrew; Gouveia, Maria; Font, Eric; Pereira, Telmo; Figueiredo, Silvério; Ferreira, Cristiana; Bridgland, David; Yang, Pu; Stevaux, José; Mota, RuiReconstruction of Pleistocene environments and processes in the sensitive geographical location of westernmost Iberia, facing the North Atlantic Ocean, is crucial for understanding impacts on early human communities. We provide a characterization of the lowest terrace (T6) of the Lower Tejo River, at Vila Velha de Rodao (eastern central Portugal). This terrace comprises a lower gravel bed and an upper division consisting of fine to very fine sands and coarse silts. We have used a multidisciplinary approach, combining geomorphology, optically stimulated luminescence (OSL) dating, grain-size analysis and rock magnetism measurement, in order to provide new insights into the environmental changes coincident with the activity of the last Neanderthals in this region. In addition, we conducted palynological analysis, X-ray diffraction measurement and scanning electron microscopy coupled with energy dispersive spectra of the clay fraction and carbonate concretions. We discuss these new findings in the context of previously published palaeontological and archeological data. The widespread occurrence of carbonate concretions and rizoliths in the T6 profile is evidence for episodic pedogenic evaporation, in agreement with the rare occurrence and poor preservation of phytoliths. We provide updated OSL ages for the lower two Tejo terraces, obtained by post infra-red stimulated luminescence: (i) T5 is c. 140 to 70 ka; (ii) T6 is c. 60 to 35 ka. The single archaeological and fossiliferous level located at the base of the T6 upper division, recording the last regional occurrence of megafauna (elephant and rhinoceros) and Mousterian artefacts, is now dated at 44 +/- 3 ka. With reference to the arrival of Neanderthals in the region, probably by way of the Tejo valley (from central Iberia), new dating suggests a probable age of 200-170 ka for the earliest Mousterian industry located in the topmost deposits of T4.
- 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.
- 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.
- Lithic technological responses to Late Pleistocene glacial cycling at Pinnacle Point Site 5-6, South AfricaPublication . Wilkins, Jayne; Brown, Kyle S.; Oestmo, Simen; Pereira, Telmo; Ranhorn, Kathryn L.; Schoville, Benjamin J.; Marean, Curtis W.There are multiple hypotheses for human responses to glacial cycling in the Late Pleistocene, including changes in population size, interconnectedness, and mobility. Lithic technological analysis informs us of human responses to environmental change because lithic assemblage characteristics are a reflection of raw material transport, reduction, and discard behaviors that depend on hunter-gatherer social and economic decisions. Pinnacle Point Site 5-6 (PP5-6), Western Cape, South Africa is an ideal locality for examining the influence of glacial cycling on early modern human behaviors because it preserves a long sequence spanning marine isotope stages (MIS) 5, 4, and 3 and is associated with robust records of paleoenvironmental change. The analysis presented here addresses the question, what, if any, lithic assemblage traits at PP5-6 represent changing behavioral responses to the MIS 5-4-3 interglacial-glacial cycle? It statistically evaluates changes in 93 traits with no a priori assumptions about which traits may significantly associate with MIS. In contrast to other studies that claim that there is little relationship between broad-scale patterns of climate change and lithic technology, we identified the following characteristics that are associated with MIS 4: increased use of quartz, increased evidence for outcrop sources of quartzite and silcrete, increased evidence for earlier stages of reduction in silcrete, evidence for increased flaking efficiency in all raw material types, and changes in tool types and function for silcrete. Based on these results, we suggest that foragers responded to MIS 4 glacial environmental conditions at PP5-6 with increased population or group sizes, 'place provisioning', longer and/or more intense site occupations, and decreased residential mobility. Several other traits, including silcrete frequency, do not exhibit an association with MIS. Backed pieces, once they appear in the PP5-6 record during MIS 4, persist through MIS 3. Changing paleoenvironments explain some, but not all temporal technological variability at PP5-6.
- Controlled experiments in lithic technology and functionPublication . Marreiros, Joao; Pereira, Telmo; Iovita, RaduFrom the earliest manifestations of tool production, technologies have played a fundamental role in the acquisition of different resources and are representative of daily activities in the lives of ancient humans, such as hunting (stone-tipped spears) and meat processing (chipped stone tools) (Lombard 2005; McPherron et al. 2010; Lombard and Phillipson 2010; Brown et al. 2012; Wilkins et al. 2012; Sahle et al. 2013; Joordens et al. 2015; Ambrose 2001; Stout 2001). Yet many questions remain, such as how and why technological changes took place in earlier populations, and how technological traditions, innovations, and novelties enabled hominins to survive and disperse across the globe (Klein 2000; McBrearty and Brooks 2000; Henshilwood et al. 2001; Marean et al. 2007; Brown et al. 2012; Režek et al. 2018).
- Late Pleistocene Landscape and Settlement Dynamics of Portuguese EstremaduraPublication . Haws, Jonathan; Benedetti, Michael; Funk, Caroline L.; Bicho, Nuno; Pereira, Telmo; Marreiros, Joao; Daniels, J. Michael; Forman, Steven L.; Minckley, Thomas A.; Denniston, Rhawn F.Here we report the results of an integrated geoarchaeological survey to study Palaeolithic human settlement dynamics in the coastal region of Portuguese Estremadura. The region has been an important focus of human occupation across multiple glacial-interglacial cycles, including periods of well-documented abrupt climate instability during MIS 3 and 2. The pedestrian survey covered a roughly 10 km wide strip of land between Sao Pedro de Muel and Peniche. The survey intensively targeted three landscape settings with Pleistocene-age surfaces and sediments: the coastal bluffs with exposed aeolian, fluvial, and colluvial sands; the Caldas da Rainha diapiric valley and associated fluvial/estuarine fills; and, Cretaceous chert-rich limestone uplands that bound the inland margin of the study area. We discovered dozens of new Palaeolithic sites, analyzed numerous Pleistocene sedimentary sections, and applied widespread OSL-dating to establish age control that allowed us to build a regional geomorphic history to contextualize Late Pleistocene human settlement across the region.
- Technology, use-wear and raw material sourcing analysis of a c. 7500 cal BP lithic assemblage from Cabeco da Amoreira shellmidden (Muge, Portugal)Publication . Paixão, Eduardo; Marreiros, Joao; Pereira, Telmo; Gibaja Bao, Juan; Cascalheira, João; Bicho, NunoThe onset of the Holocene is marked by new human ecological adaptations that are associated with the origins of the Mesolithic in the Atlantic Iberia coast. During the Mesolithic, shellmidden deposits become one of the most relevant and interesting prehistoric archeological contexts, interpreted has the result of intensive human ecological exploitation, and marked by new settlement and mobility patterns, and subsistence strategies. Based on techno-typological patterns and artifact density, each Muge shellmidden has been traditionally linked to a single and specific functionality, possibly reflecting the presence of different stylistic/ethnic groups in the territory. Therefore, characterizing settlement, mobility, site function, and technological patterns in each shellmidden is fundamental to understand the archeological record and answer major questions related to human ecological behavior during the onset of the new Holocene climatic setting. This paper presents new data on the Mesolithic from the Tagus valley, using the case study of the lithic assemblage from layer 2 of Cabeco da Amoreira shellmidden. From our interpretation, by combining lithic raw material characterization and sourcing, techno-typological and use-wear analysis, this study aims to represent an important step on understanding resource exploitation, technological systems and site function, in order to address intra and inter-site variability. In what concerns lithic raw materials, they can be found in the Pleistocene gravels that compose the upper section of the Cenozoic deposits of the River Tagus, including those underneath the site. Nevertheless, the geochemical results suggest that the chert used has correspondence with local, regional, and exogenous areas. In sum, by characterizing the Cabeco da Amoreira shellmidden lithic assemblage, results and data aim to contribute to the discussion and new interpretations on shellmiddens' function and settlement occupation patterns during the Mesolithic.
- Understanding Neanderthal technological adaptation at Navalmaillo Rock Shelter (Spain) by measuring lithic raw materials performance variabilityPublication . Abrunhosa, Ana; Pereira, Telmo; Marquez, Belen; Baquedano, Enrique; Luis Arsuaga, Juan; Perez-Gonzalez, AlfredoNavalmaillo Rock Shelter is an Upper Pleistocene archaeological site in the Lozoya River Valley (Madrid, Spain) with a quartz-based Mousterian lithic assemblage. To understand the reasons behind an intense use of quartz over flint and quartzite, a mechanical experiment was carried out. Flakes from flint, quartzite, and local quartz were tested under controlled conditions and quantifiable variables. The mechanical action consisted in a standardised linear repetitive cutting protocol over antler and pine wood. Results allowed to differentiate flake resistance between raw materials through mass and edge angle material loss statistics. Results also showed that the edges produced on flint are sharper allowing to create deeper cuts, but the thin working edges break more easily meaning that they would need a higher maintenance by retouch. Quartzite and quartz have similar performances, but quartzite suffers a more intense modification of the edge angle, while quartz edges present a higher endurance. When compared with flint, quartzite and quartz are more suitable for those tasks where heavier force is applied. Based on that, we concluded that there was no functional disadvantage in using a quartz-based toolkit. Therefore, the quartz assemblages recovered throughout the sequence of Navalmaillo Rock Shelter show that it was intensely explored not just because of its availability in the landscape but also for its suitability to the development of the different activities taking place at Navalmaillo Rock Shelter such as big sized herbivore butchering, for a long time span.