Browsing by Author "Pereira, Telmo"
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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.
- 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.
- 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).
- 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.
- Evidence of specialized resource exploitation by Modern Humans in Western Iberia associated to Pleistocene and Holocene extreme environmental conditionsPublication . Pereira, Telmo; Monteiro, Patrícia; Paixão, Eduardo; Nora, David; Évora, Marina; Simões, Carlos; Detry, Cleia; Assis, Sandra; Carvalho, Vânia; Holliday, TrentonThroughout prehistory, landscapes were repeatedly subjected to both global and localized climatic fluctuations that changed the regional environments where human groups lived. This instability demanded constant adap-tation and, as a result, the functionality of some sites changed over time. In this light, the western coast of Iberia represents an exceptional case study due to the proximity between at least some oceanic cores and archaeological sites, which should facilitate an accurate reconstruction of the re-lationships between paleoenvironmental conditions and the coeval patterns of human behavior. This region, and in particular the valley of the River Lis, is marked by wide exposed plateaus cut by narrow and deep canyons. In this paper we present the stratigraphic, archaeometric, technological and archaeobotanical record of Pogo Rock Shelter, located in one of these canyons, which hints at the human responses to such changes, and discuss the link between its Solutrean and Epipaleolithic occupations to specific activities. During the coldest part of the Last Glacial Maximum, we hypothesize that there was intensive exploitation of a chert outcrop above the roof to produce blades and Solutrean tips. Later, during Bond Event 6, after that outcrop had been exhausted, there was intensive consumption of shellfish gathered between the mouth of the canyon and the sea. We hypothesize that these strikingly different roles demonstrate how hunter-gatherers adapted to local conditions, and exploited specific resources, promising to provide a better understanding about its functional role during specific extreme climate events.
- Human adaptive responses to climate and environmental change during the Gravettian of Lapa do Picareiro (Portugal)Publication . Haws, Jonathan; Benedetti, Michael; Carvalho, Milena; Ellis, Grace; Pereira, Telmo; Cascalheira, João; Bicho, Nuno; Friedl, LukasOn the Iberian Peninsula, abrupt climate shifts during the Late Pleistocene impacted human and natural systems. Our knowledge of human adaptive responses to these climatic perturbations has improved in recent years with the development of new radiocarbon techniques that have increased the temporal resolution of cultural chronologies. At the same time, new high-resolution paleoclimatic records from Greenland ice cores, deep-sea sediment cores, speleothems, and microfaunal assemblages have permitted detailed paleoenvironmental reconstructions. Combined with the archaeological record of culture change, these data sets allow for a better understanding of the nature of human socio-ecological systems during the Late Pleistocene. Here we present new data on the Gravettian occupations at Lapa do Picareiro, a cave site in Portugal with a long continuous stratigraphic sequence spanning MIS 3 and 2. The ongoing excavation of Lapa do Picareiro has revealed at least three Gravettian levels with very different patterns of raw material use and technological reduction. The Early Gravettian levels contain a quartzite flake assemblage with several refitting clusters and a small chert assemblage with nosed endscrapers and bladelet technology. The Late or Terminal Gravettian level contains carinated endscraper/core-bladelet technology, mainly quartz, with chert blade production, and a few bone tools. The faunal assemblages also have a different character. Both contain a similar range of medium and large ungulates but the earlier Gravettian has a much richer and more diverse assemblage of small animals. These combined archaeological data sets provide a new perspective on Gravettian human adaptations in response to climate shifts, especially Heinrich Event 3 and Greenland Interstadials 4 and 3.
- Intra-observer reproducibility and inter-observer agreement of Fels skeletal age assessments among male tennis players 8–16 yearsPublication . Sousa-e-Silva, Paulo; Coelho-e-Silva, Manuel J.; Celis-Moreno, Jorge M.; Costa, Daniela C.; Martinho, Diogo V.; Ribeiro, Luís Pedro; Oliveira, Tomas; Gonçalves-Santos, João; Tavares, Oscar M.; Castanheira, Joaquim M.; Pereira, Telmo; Conde, Jorge; Cayolla, Ricardo R.; Duarte-Mendes, Pedro; Myburgh, Gillian K.; Cumming, Sean P.; Malina, Robert M.Background Skeletal age (SA) is an estimate of biological maturity status that is commonly used in sport-related medical examinations. This study considered intra-observer reproducibility and inter-observer agreement of SA assessments among male tennis players. Methods SA was assessed with the Fels method in 97 male tennis players with chronological ages (CA) spanning 8.7–16.8 years. Radiographs were evaluated by two independent trained observers. Based on the difference between SA and CA, players were classified as late, average or early maturing; if a player was skeletally mature, he was noted as such as an SA is not assigned. Results The magnitude of intra-individual differences between repeated SA assessments were d = 0.008 year (observer A) and d = 0.001 year (observer B); the respective coefficients of variation were 1.11% and 1.75%. Inter-observer mean differences were negligible (t = 1.252, p = 0.210) and the intra-class correlation coefficient was nearly perfect (ICC = 0.995). Concordance of classifications of players by maturity status between observers was 90%. Conclusion Fels SA assessments were highly reproducible and showed an acceptable level of inter-observer agreement between trained examiners. Classifications of players by skeletal maturity status based on assessments of the two observers were highly concordant, though not 100%. The results highlight the importance of experienced observers in skeletal maturity assessments.
- 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.
- Lithic economy and territory of Epipaleolithic hunter-gatherers in the Middle Tagus: The case of Pena d'Agua (Portugal)Publication . Pereira, Telmo; Andrade, Catarina; Costa, Mafalda; Farias, Anne; Mirão, José; Carvalho, António FaustinoIn Central Portugal (westernmost Eurasia) the transition from the traditional Pleistocene hunter-gatherer societies to the complex Mesolithic societies of the Holocene has been debated for decades. While some argue that these differences were a progressive phenomenon that started with the shift from the Pleistocene to the Holocene, others defend that the Late Pleistocene patterns were fairly similar to those of the Epipaleolithic and that the major shift was rapid, dramatic and triggered by the necessary adaptation to the 8.2 ka cal BP (8.09-8.25 ka cal BP) climatic event. The study of lithic raw material provenance might be useful for this discussion, since it has been suggested that the Magdalenian and Epipaleolithic populations from this region were collecting this resources within a close range territory, whereas the Mesolithic populations were acquiring them at longer distances.In this paper, we present the results from p-XRF, VP-SEM-EDS and mu-XRD analysis done on the Epipaleolithic lithic assemblage from Pena d'Agua Rockshelter, and in some geological samples from secondary sources located similar to 14 km from this site. This layer is of major relevance for this debate since it is dated from 8.19 ka cal BP. If the transition was gradual, it would be expected that this assemblage would show some traits of higher-complexity seen in the Mesolithic, namely of longer distance acquisition. However, our results indicate correspondence between the archaeological chert types and some of the geological sources. The differences seen between the archaeological specimens and geological samples are mostly present in traits that can be related with manufacture, handling and post-depositional phenomena.The results suggest that, in what concerns to the economy of abiotic resources, the Epipaleolithic populations living at the time of the dramatic 8.2 ka cal BP cold event, were performing a short range acquisition of lithic raw materials which reinforces the idea of continuity from the Late Pleistocene to the 8.2 ka cal BP event and an abrupt and dramatic shift soon after this phenomena. (C) 2015 Elsevier Ltd and INQUA. All rights reserved.
- Lithic technological adaptation within the Gravettian of the Iberian Atlantic region: results from two case studiesPublication . Bradtmoller, Marcel; Marreiros, Joao; Pereira, Telmo; Bicho, NunoThe origins and expansion of Gravettian industries in Western Europe have recently been considered a cultural mosaic phenomena marked by regional technological facies. Probably associated with climatic oscillations, the development of these facies is likely related to sociocultural patterns and human adaptations to different ecological niches. Thereby, changes of subsistence strategies and mobility patterns are also reflected by technological and typological adaptations and innovations within the lithic assemblages. With the Iberian Peninsula being an important ecological niche for studying these phenomena, we conducted a comparative analysis of two occupations to test human ecological and lithic technological adaptations during the early Gravettian in Iberia: Cueto de la Mina on the northern Iberian Atlantic coast and Vale Boi on the western Portuguese Atlantic coast. Results show that these occupations exhibit major technological differences, but also strong similarities in the case of typological innovation/adaptation, possibly related to local resource accessibility (e.g. high-quality raw material). Based on these observations, the study provides further information concerning possible connections throughout the Iberian Atlantic coastline during an early Gravettian timeframe. (C) 2015 Elsevier Ltd and INQUA. All rights reserved.