Percorrer por autor "Iovita, Radu"
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- Agent-based simulations reveal the possibility of multiple rapid northern routes for the second Neanderthal dispersal from Western to Eastern EurasiaPublication . Coco, Emily; Iovita, Radu; Marco PeresaniGenetic and archaeological evidence imply a second major movement of Neanderthals from Western to Central and Eastern Eurasia sometime in the Late Pleistocene. The genetic data suggest a date of 120−80 ka for the dispersal and the archaeological record provides an earliest date of arrival in the Altai by ca. 60 ka. Because the number of archaeological sites linking the two regions is very small, the exact route taken and its timing have been the matter of considerable debate. In particular, climate change in this period modified landscapes considerably, changing the cost of moving in different directions. Here, we apply agent-based least-cost path simulations for the first time to Neanderthals, showing that they most likely took a northern route through the Urals and southern Siberia under all climate scenarios. Agents leaving either the southern or the northern Caucasus Mountains reach the Altai in less than 2000 years during two time windows when the climate was mild, in MIS 5e (the Last Interglacial) and in MIS 3. The latter coincides with the dated presence of Neanderthals at Chagyrskaya and Okladnikov Caves in the Altai. The results of this modeling approach demonstrate a remarkable east-west geographic connectivity of northern Eurasia via river corridors despite the presumed barriers of the Ural Mountains and major north-south flowing rivers. Our results highlight the unique strengths of agentbased simulations to reconstruct pathways for ancient migrations.
- 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).
- Use-wear analysis shows changing handaxe grip and use across time at la noira (France)Publication . Rodriguez, Alice; Coco, Emily; Moncel, Marie-Hélène; Despriée, Jackie; Hardy, Bruce; Iovita, RaduHandaxes — sub-oval bifacially flaked stone tools — were produced for over a million years across Africa, Europe, and Asia during the Lower Palaeolithic. Their relatively uniform shape across varied environments and over a million years raises the question of whether or not their function and purposes were also uniform. Previous studies suggested that handaxe shape might be related to patterns in use and maintenance, but the level of analysis may have been too coarse to tease out specific uses. This study investigates the function of handaxes from two successive Acheulean occupations at the la Noira site (France), separated by ca. 200 ka. This research aimed to find out how hominins generally used handaxes through microscopic use wear analysis. Specifically, we documented macro-wear characteristics such as type (micro-scars, edge crushing, striations, edge rounding, polish), and their relative position and distribution. We used a Geographic Information System (GIS) to translate these observations into wear location heatmaps — visual representations highlighting areas of intense or repeated use — and compared these across different occupation periods. The analysis revealed that similar handaxes were likely held in different ways and used for different tasks during the two phases of occupation at la Noira, at 700 ka and respectively 450 ka. These findings suggest a more complex scenario of handaxe use than previously understood, including changes in tool use modalities over time that reflect changes in handaxe function and hominin technical behaviors.