Histoire Naturelle de l’Homme Préhistorique

Homo luzonensis lived during the upper Pleistocene in the northern Philippines, east of the Wallace line. The few specimens attributed to this species show a mosaic of plesiomorphies for the genus Homo and apomorphies found in upper Pleistocene Homo species. Plesiomorphic traits could result from a close phylogenetic relationship with Australopithecus or Homo habilis/rudolfensis or from insular evolution favouring reversals, possibly linked to a relationship with a more recent species like Homo erectus. We conducted a cladistic analysis based on dental and postcranial remains of adult H. luzonensis to test these hypotheses. The trees obtained indicate that both hypotheses are supported by different anatomical elements. The trees suggesting H.luzonensis is close to H. erectus (as a sister-taxon or as a close relative of H. erectus) are supported by dental characters and feature high retention and consistency indices. Moreover, H. luzonensis likely had reduced body size and postural/locomotor modifications, similar to other insular mammals with medium-to-large-sized ancestors. The tropical forest environment of Luzon Island may have favoured the selection of these features. Based on these results and our current knowledge of insular evolution, we suggest that H. luzonensis likely evolved from an Asian H. erectus population in an insular context.

The early Middle Pleistocene is characterized by a significant turnover in the fauna across Europe, creating new niches and new subsistence opportunities for hominin populations. Open-air sites provide a unique opportunity to study the distinct and effective resource acquisition strategies that were developed by hominins during this period. The archaeological site of Notarchirico (695-610 ka) is a key locality for the study of the behavior of hominin groups in the Italian Peninsula and Western Europe. The site is one of the few open-air sites to have yielded human remains, namely a femur fragment of Homo heidelbergensis, in such ancient chronologies. Notarchirico also yielded numerous lithic and faunal remains, although the latter, despite their abundance, have so far received scarce attention from a taphonomic perspective. Here we present a study of the site, including material from both ancient and modern collections. Spatial and taphonomic inferences can be drawn about the formation of the assemblages, as well as behavioral inferences about the Middle Pleistocene hominin populations. Despite the poor preservation of the bones, the data suggest that both hominins and carnivores foraged in the area. From a taphonomic perspective, spatial analyses suggest that water flows may have altered the association between osteological and lithic assemblages. There is compelling evidence that suggests that hominin groups inhabited the area surrounding the site for a minimum of 100 ka as the region was abundant in resources. Notarchirico is a pivotal site for understanding the adaptation of hominins and their interaction with the Middle Pleistocene ecosystems.

<strong class="journal-contentHeaderColor">Abstract.</strong> The impact of rapid climate variability on Neanderthal population in Europe during the Last Glacial (Marine Isotope Stages 4-2), including Dansgaard-Oeschger cycles and Heinrich events, has been the subject of a long-standing debate. However, few studies have focused on the nature and impact of such rapid variations on human population during earlier periods. A growing number of high-resolution paleoclimatic archives supports the persistence of rapid oscillations during the penultimate glaciation (MIS 6), and the close response of Mediterranean ecosystems to these. Still, few palynological sequences in the Mediterranean region offer sufficient resolution to document vegetation dynamics during this time. Pollen records are especially lacking in the western Mediterranean, a key region to understand the connection between North Atlantic and Mediterranean climatic influences. This region is also traditionally considered a climatic refugium for human population during unfavourable periods. We provide new palynological data covering MIS 6 from the long and continuous marine record of ODP 976 in the Alboran Sea. A total of 200 samples, spanning the interval from 196 to 127 ka Before Present (BP), reveal both long-term trends and rapid fluctuations in regional vegetation composition. A multi-method approach, including modern analogues, regression, and machine learning approaches, was applied to ODP 976 pollen assemblages to reconstruct the annual/seasonal temperatures and precipitation. Results show that three phases can be identified. The first phase (187&ndash;166 ka BP) is characterized by significant oscillations of temperate trees and rather cool and humid conditions during early MIS 6, coincident with a sapropel layer deposition in both the western and eastern Mediterranean. In the second phase (165&ndash;144 ka BP), arid herbaceous vegetation is dominant, marking the main imprint of glacial maxima conditions and reduced climate variability. The third phase (144&ndash;129 ka BP) is marked by the development of Ericaceae and increased annual precipitations. At the end of MIS 6 glaciation, an strong cooling and intense episode of steppe and semi-desert expansion is identified as Heinrich Stadial 11 (135&ndash;129 ka BP), marking a distinct pattern for Termination II in the Western Mediterranean. Rapid oscillations appear like a pervasive feature of the Penultimate glacial in the SW Mediterranean, though they present reduced amplitude and frequency compared to the Last Glacial. A synthesis of human occupation shows that a mosaic of traditional (Mode 2) and innovative (Mode 3) technological features is observed. Although the data are scarce, Neanderthal seems to have continuously inhabited Western Mediterranean regions across the penultimate glacial. The severe climate conditions during Heinrich Stadial 11 (~133&ndash;129 ka BP) might have played a role in the apparent population contraction at the end of MIS 6, and perhaps also in the definitive abandonment of Lower Palaeolithic industries.

Abstract The world at 18,000 BP , published by Gamble and Soffer (The world at 18,000 BP. Vol. 2: low latitude, Unwin Hyman, 1990), represents the first, and so far the only, attempt at characterising and discussing the impact of the Last Glacial Maximum (LGM) on human societies on a global scale. At the time, they highlighted that research and data on the LGM in southern latitudes and the tropics in particular were scant. Since 1990, however, many sites dated to the LGM and located in tropical latitudes have been published. Many paradigms have changed regarding the peopling of the Americas, which allows the archaeology of this continent to be integrated into global scale studies of the LGM. The development of Pleistocene archaeology in tropical contexts, in parallel with methodological advances in cultural, geosciences and palaeoenvironmental studies have strongly reshaped what we know of the antiquity of human occupation in tropical regions and specific human–environment interactions. This article provides for the first time a pan-tropical perspective on the impact of the LGM on human groups living within the tropical latitudes, drawing from case studies in Southeast Asia, Africa and South America, specifically regions which have up until now never been discussed together. To this end, we focus on six different tropical regions between 30 and 10 ka. We present the archaeological and paleoenvironmental data available in these areas, along with proposed relationships for variations in these two records. Finally, we discuss at the regional scale the presence or absence of human changes (site density and techno-cultural change or continuity) before, during and immediately after the LGM.

Geological data of the region indicate that the Canary Islands have not been connected to the mainland before. However, fossil evidence suggests some kind of faunal exchange with Africa during the late Neogene. After extensive field work during past years, a re-evaluation of the fossil remains of the first terrestrial vertebrates that settled and thrived on the Canary Islands is presented, with special attention to the long-debated identity of birds that laid large-sized eggs, reported some decades ago on Lanzarote Island. The age of the eggshell-bearing deposits has been recently updated as Early Pliocene (ca. 4 Ma). The dispersal mode of these terrestrial birds to reach the island was an unsolvable challenge in previous studies because the regional geography of the sea bottom was neglected, as well as the chronological succession of events in the formation of the Canary Eastern Ridge, which increased attention to a unique case of arrival of ratites on an island never before united with the mainland. The few animals found in northern Lanzarote (ratites, snakes, turtles, terrestrial snails and bite marks on eggshells pointing to a jagged and unknown large predator) probably made the sea crossing from the mainland in different ways. Two scenarios are contemplated. In both, the circumstances facilitating the faunal transit from Africa to the Canaries ceased after the early Pliocene, around 4 Ma, since these animals have never managed to cross the Canary Channel again.

Research on brain evolution centres mainly on internal mouldings of the skull, known as endocasts; however, the relationship between the size and asymmetry of the brain and endocasts has been poorly investigated in humans. Therefore, the main objective of this study was to investigate whether endocasts can be reliable indicators of brain size and asymmetry. Magnetic Resonance Imaging (MRI) of 75 participants was used to calculate the volume and surface area of the brain, the endocast, and their respective hemispheres. Two asymmetry indices (i.e. directional and absolute asymmetry) were used to assess the differences in volume and surface area between the sides of the brain and endocast. The Pearson correlation coefficient was calculated to assess the relationships between the parameters, and a Monte Carlo simulation for linear regression was performed to generate prediction equations for brain volume. The relationships between the level and direction of asymmetry indices were investigated using the Pearson correlation and McNemar's test, respectively. All correlations were statistically significant; however, correlation coefficients between volumes were stronger (0.894-0.931) than between volumes and surface areas (0.783-0.834). Brain volume can be predicted with high accuracy (ranging between 0.80 and 0.87) using the endocast total volume or the volume of one of the sides. The associations between the levels of asymmetry indices of the brain and endocast were non-significant; however, the McNemar's test indicated that endocasts show the same left- or right-biased asymmetry as the brain. This was the first study conducted on a large sample of brain and endocast data from the same individuals. The results demonstrated that brain volume can be accurately reconstructed using the volume of the endocast or one of its sides. This finding is especially important in the context of reconstructing fossil skulls, which are usually fragmented. Conversely, the asymmetry levels of endocast parameters are not reliable indicators of the actual level of brain volume asymmetry. Future research on fossils should focus on endocast asymmetry direction (left- or right-biased) as this closely corresponds with brain lateralisation.

<strong class="journal-contentHeaderColor">Abstract.</strong> Quartz Optically Stimulated Luminescence (OSL) and Electron Spin Resonance (ESR) offer valuable quantitative tools both for Quaternary sediment dating but also for understanding sediment provenance and dynamics. However, the variability of quartz sensitivity remains an issue, attributed either to the intrinsic properties of source bedrock, to processes during sediment transport and deposition, or to both. This study addresses these questions by investigating quartz from magmatic, metamorphic, and sedimentary formations in the Strengbach catchment (Vosges Massif, France). Using a combination of ESR, OSL, and LA-ICPMS trace element analyses, our study reveals significant relationships between quartz OSL/ESR sensitivities and source bedrock characteristics, such as lithology, crystallization conditions, and deformation histories. ESR Ti-centre and OSL signals are notably influenced by trace elements like Al, Li, and Ti. Samples that underwent high pressure during metamorphism along with those located in the tectonic shear zone show both lowest OSL and ESR intensities, while higher sensitivities are observed in plutonic rocks and sandstones. This suggests that (i) pressure can be one of the prevailing factors driving changes in OSL/ESR sensitivities (ii) enhanced OSL sensitivity in mature and recycled sediments underscores the impact of sedimentary transport and reworking. Our results highlight the need for careful interpretation of ESR and OSL signals, both for dating or sourcing, particularly in sediments derived from metamorphic terrains.

<strong class="journal-contentHeaderColor">Abstract.</strong> Quartz Optically Stimulated Luminescence (OSL) and Electron Spin Resonance (ESR) offer valuable quantitative tools both for Quaternary sediment dating but also for understanding sediment provenance and dynamics. However, the variability of quartz sensitivity remains an issue, attributed either to the intrinsic properties of source bedrock, to processes during sediment transport and deposition, or to both. This study addresses these questions by investigating quartz from magmatic, metamorphic, and sedimentary formations in the Strengbach catchment (Vosges Massif, France). Using a combination of ESR, OSL, and LA-ICPMS trace element analyses, our study reveals significant relationships between quartz OSL/ESR sensitivities and source bedrock characteristics, such as lithology, crystallization conditions, and deformation histories. ESR Ti-centre and OSL signals are notably influenced by trace elements like Al, Li, and Ti. Samples that underwent high pressure during metamorphism along with those located in the tectonic shear zone show both lowest OSL and ESR intensities, while higher sensitivities are observed in plutonic rocks and sandstones. This suggests that (i) pressure can be one of the prevailing factors driving changes in OSL/ESR sensitivities (ii) enhanced OSL sensitivity in mature and recycled sediments underscores the impact of sedimentary transport and reworking. Our results highlight the need for careful interpretation of ESR and OSL signals, both for dating or sourcing, particularly in sediments derived from metamorphic terrains.