Universite Bordeaux Montaigne

The timing and mechanisms underlying the gradual replacement of Neanderthal populations by Homo sapiens groups have elicited heated debate for decades. The Châtelperronian of France and northern Spain has figured prominently in these discussions. While the Neanderthal authorship of this techno-complex is far less certain than previously thought, the Châtelperronian is now generally accepted as being among the first genuine Upper Paleolithic industries in Eurasia rather than a “transitional” stone tool technology. Here, we report the first association of shell beads with Châtelperronian artifacts from new excavations at the site of La-Roche-à-Pierrot, Saint-Césaire (France), supported by a multiproxy spatial analysis that incorporates site formation processes. Similar types of personal ornaments are unknown from Middle Paleolithic contexts. Comparable examples have, however, been recovered from contexts penecontemporaneous with the Châtelperronian in south-eastern Europe and around the Mediterranean. This hitherto undocumented combination of an early Upper Paleolithic industry and shell beads provides insights into cultural variability in western Europe and raises the question as to whether the makers of the Châtelperronian were influenced by or formed part of the earliest dispersals of H. sapiens into the region.

Microplastics (MPs) are increasingly detected in aquatic environments and are a growing concern due to their persistence, mobility, and potential risks to ecosystems and human health. This study aims to investigate the presence of MPs (>20 μm) across the urban water cycle of Geneva (Switzerland). The scope of the assessment includes large water volumes (50-2000 L) of raw water sources (groundwater and surface water), drinking water treatment, water supply network, and effluents of three wastewater treatment plants. MPs concentrations, size distributions, and chemical compositions were determined across these interconnected systems. Sampling and analysis followed a strict quality assurance protocol aligned with current MP analysis guidelines and standards. Fourier-transform infrared spectroscopy (FTIR) was used to characterise MPs. Geneva's main conventional drinking water treatment plant (serving approximately 500,000 consumers) showed high removal efficiency, reducing MPs concentrations from 640 ± 292 MP/m³ in raw water to 10 ± 6 MP/m³ after treatment (including coagulation, sand filtration, ozonation and granular activated carbon filtration), demonstrating a removal efficiency of 97 ± 3 %. Groundwater samples showed low concentration of MPs (8 ± 7 MP/m³). However, the drinking water supply network (DWSN) contributed to an increase of MPs concentration, with values equal to 27 ± 37 MP/m³ in the eastern section and 23 ± 19 MP/m³ in the western section. Effluents from wastewater treatment plants (WWTPs) exhibited the highest concentrations, averaging 5829 ± 5108 MP/m³. This study highlights the importance of full-cycle monitoring and supports the need for improved mitigation strategies across all stages of the urban water cycle.

The segmental composition of the arthropodan head is a long-standing biological question. This is particularly controversial in insects where considerable fusion and modification obfuscate the postembryonic segmentation. Here we propose a reinterpretation of the insect head morphology and segmentation, which also accords with current genetic and embryological data. The new interpretation of a generalized insect head is based on the discovery of intercalary segment remnants (the intercalates), thanks to the use of 3D-reconstruction of a Cretaceous thripidan and to a reassessment of the 'anterior tentorial arm' as the anteriormost part of a lateral segmental suture from the contact of the head lobe and gnathal segments during development. We show that the two-jointed mandibular articulation is likely symplesiomorphic for Insecta, no longer supporting the clade 'Dicondylia', the most diverse lineage of all insects. We discuss new perspectives on the 'labrum' in Pancrustacea.