Géologie Méditerranéenne

Abstract Quaternary hominin-carnivore interactions is taphonomically reconstructed best through the use of bone surface modifications (BSM). This study examines redundancy in an experimental dataset of potentially similar BSM created by crocodile tooth-marking, sedimentary trampling and stone tool cut marking (Domínguez-Rodrigo and Baquedano in Sci Rep 8:5786, 2018). The original analysis of this experimental set, aiming to confidently classify the three types of BSM, was criticized by some authors (McPherron et al. in J Hum Evol 164:103071, 2022) insinuating that the analysis was flawed by a potential methodological overfitting caused by the improper use of bootstrap. A subsequent response to that critique (Abellán et al. in Geobios Memoire Special. 72–73, 12–21, 2022) showed that there was no difference in the results between using the raw data and the bootstrapped data. It was argued that structural co-variance and redundancy of the categorical dataset was responsible for the highly accurate models; however, this was never empirically demonstrated. Here, we show how the original experimental dataset is saturated with redundancy. Our analysis revealed that, out of 633 cases, only 116 were unique (18.3%) in the complete dataset, 45 unique cases (7.1%) in the intrinsic variable dataset, and just four unique cases (0.63%) in the three-variable dataset (accounting for most of the sample variance). Redundancy, therefore, ranged from 81.7% to over 99%. Machine learning analysis using Random Forest (RF) and C5.0 algorithms on the datasets demonstrated high accuracy with the raw data (90-98%). Proper bootstrapping yielded nearly identical accuracy (88-98%), while improper bootstrapping slightly reduced accuracy (86-98%) and introduced some degree of underfitting. This underscores that the potential biasing effects of bootstrapping differ between numerical and categorical datasets, especially on those with low dimensionality and low cardinality, in situations of feature interdependence and covariance. A complementary approach, consisting of an iterative data partitioning method through train-test resampling reproduced the results derived from the bootstrapped samples. The understanding of these methodological processes is essential to an adequate application of these experimental models to the fossil record.

Abstract This research presents an historical background and an analytical and study of a bell dating back to the 20th century, currently located at Al Salam Modern School, an ancient school, formerly known as the American College in Asyut, Egypt, which was established during the period between 1901 and 1909. The bell consists of metal parts (Bowl, Yoke, Standards, Clapper, Clevis Bolt, Toller, and Bearing) and wooden parts (Base or Frame and Wheel). These components were studied and analyzed using microscopic examination, Portable X-ray fluorescence (p-XRF) Scanning electron microscopy (SEM), coupled with an energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Visual and microscopic examination revealed the presence of corrosion products on the surface of the bell and its metal parts, bird droppings, embrittlement of the wood structure, fiber breakage, and accumulation of dust. The bell’s wooden parts were identified as oak using a light microscope. The body of the bell itself was analyzed using p-XRF and EDX, which revealed that the alloy used for its making is mainly composed of copper and tin, known as tin-bronze alloy. XRD analysis was used to identify the corrosion products on the surface of the bronze bell as well as the corrosion products of the parts made of iron. The results revealed that the corrosion products formed on the bell surface are Nantokite, Paratacamite, Atacamite, Brochantite, Antlerite, Cassiterite and Gypsum, while the rust products on the iron parts are Magnetite, Hematite, Goethite, Akaganeite, Lepidocrocite and Gypsum. FTIR analysis of the wooden parts of the bell showed the embrittlement and the decomposition of hemicellulose and lignin. This analysis also showed that the paints used in painting the wooden parts is a local paint known as ARTEX (Pachin). 

Abstract The identification of the duration of Neanderthal occupations is a tricky topic by the palimpsest nature of archaeological assemblages. This study explores the challenges associated with distinguishing between long and short-term occupations, using qualitative and quantitative data from relevant archaeological sites in the Late Middle Palaeolithic in Spain and south-eastern France. We highlight the proposed occupation models and their specific characteristics, considering the heterogeneity of archaeological evidence and the limitations of current methodologies. The article offers a reassessment of the topic, critically analysing the current indicators used to determine the duration of Neanderthal occupations. Furthermore, we discuss the complexity in defining the concepts of short and long-term occupation, emphasising the need for a multidisciplinary approach to fully understand the complexity of the practices of the Late Neanderthals. 

Abstract Due to the scarcity of stratified and well-dated archaeological horizons, diachronic as well as spatial patterns of Pleistocene lithic traditions are not very well understood in Arabia. To contribute to this topic, we present new archaeological, sedimentological and chronological data from archaeological horizon II (AH II), the stratigraphically youngest Middle Palaeolithic assemblage at Jebel Faya, Emirate of Sharjah, United Arab Emirates. Results of optically stimulated luminescence dating reveal that AH II was deposited about 80 ka ago at the end of Marine Isotope Stage 5 (MIS 5). The lithic assemblage shows a preference for elongated flakes and blades produced predominantly by bidirectional methods, both Levallois and non-Levallois. The few tools feature simple retouch often forming denticulated edges. Contemporaneous assemblages from Arabia are rare and show distinct technological characteristics, including a preference for the production of flakes with ovoid and triangular morphologies from centripetal as well as unidirectional convergent and bidirectional convergent Levallois methods. These differences indicate that traditions in the production of stone tool blanks follow distinct trajectories north and south of the Rub al-Khali desert at the termination of the MIS 5 humid period.

Abstract For the first time, the three bronze doors of the Lateran Baptistery and Cloister of the Archbasilica of St John Lateran in Rome have been studied to determine their chemical composition and to obtain further information about their manufacture. The doors studied include two made at the end of the twelfth century by Pietro and Uberto from Piacenza, Italy, and one made by an unknown master in the fifth century. This door now leads to the Oratory of St John the Baptist in the Lateran Baptistery. One of the 12th-century doors is now in the Chapel of St. John the Evangelist, and the second 12th-century door is in the cloister of the Archbasilica. High-resolution photographic documentation and a 3D model of one of the door wings complete the detailed documentation of the three medieval doors. The chemical analysis of the doors permits a detailed reconstruction of the alloys used in their manufacture. All doors were made of leaded tin bronze, and the resulting data provides a valuable contribution to the history of their construction and the processes employed in their manufacture.