Very little is known about Neanderthal cultures, particularly early ones. Other than lithic implements and exceptional bone tools, very few artefacts have been preserved. While those that do remain include red and black pigments and burial sites, these indications of modernity are extremely sparse and few have been precisely dated, thus greatly limiting our knowledge of these predecessors of modern humans. Here we report the dating of annular constructions made of broken stalagmites found deep in Bruniquel Cave in southwest France. The regular geometry of the stalagmite circles, the arrangement of broken stalagmites and several traces of fire demonstrate the anthropogenic origin of these constructions. Uranium-series dating of stalagmite regrowths on the structures and on burnt bone, combined with the dating of stalagmite tips in the structures, give a reliable and replicated age of 176.5 thousand years (±2.1 thousand years), making these edifices among the oldest known well-dated constructions made by humans. Their presence at 336 metres from the entrance of the cave indicates that humans from this period had already mastered the underground environment, which can be considered a major step in human modernity.

In this study, Raman microspectroscopy is applied to investigate two manganese oxide phases: lithiophorite [(Al,Li)Mn 4+ O 2 (OH) 2 ] and asbolane [(Ni,Co) x Mn 4+ (O,OH) 4 ·nH 2 O], along with their intermediates ('asbolane-lithiophorite intermediates': ALI). These oxides typically incorporate variable concentrations of Co, Ni, Cu and Li. They represent a group of economically interesting phases that are difficult to identify and characterize with classical X-ray diffraction techniques. We show that Raman micro spectroscopy is useful to the investigation of those phases, but they require to be tested in very low laser power conditions to avoid sample degradation (e.g. 0.2 mW with λ = 532 nm). We propose reference Raman spectroscopic signatures for lithiophorite, asbolane and ALI phases. These spectra are mainly composed of two spectral domains, the first one is located between 370 and 630 cm À1 and the second one between 900 and 1300 cm À1 . We then assess the impact of their highly variable chemistry on their Raman peak positions, intensities and FWHM using a semi-systematic curve-fitting method profiled for these phases.

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Despite uncontested evidence for fossils belonging to the early hominin genus Australopithecus in East Africa from at least 4.2 million years ago (Ma), and from Chad by 3.5 Ma, thus far there has been no convincing evidence of Australopithecus, Paranthropus or early Homo from the western (Albertine) branch of the Rift Valley. Here we report the discovery of an isolated upper molar (#Ish25) from the Western Rift Valley site of Ishango in Central Africa in a derived context, overlying beds dated to between ca. 2.6 to 2.0 Ma. We used µCT imaging to compare its external and internal macro-morphology to upper molars of australopiths, and fossil and recent Homo. We show that the size and shape of the enamel-dentine junction (EDJ) surface discriminate between Plio-Pleistocene and post-Lower Pleistocene hominins, and that the Ishango molar clusters with australopiths and early Homo from East and southern Africa. A reassessment of the archaeological context of the specimen is consistent with the morphological evidence and suggest that early hominins were occupying this region by at least 2 Ma.

Natural manganese oxides characterization represents a challenge due to the broad variety of their structures and geochemical compositions along with a frequent poor crystallinity. This characterization requires the ability to conduct both a phase separation and a phase association operation. In this paper, the Raman spectra acquired on a selection of natural manganese oxide minerals are first processed with an automated curve‐fitting model called MnOx. The adjustment of convolution envelope is realized, thanks to the Levenberg–Marquardt algorithm applied on a set of randomly generated seed pseudo‐Voigt curves. The application conditions of the automated curve‐fitting and, in particular, the number of seed curves are investigated with regards to the risk of overfitting. The MnOx model outputs are in a second step treated by data mining techniques and in particular by unsupervised clustering methods. This data processing shows promising results in terms of phase separation when the number of clusters is equivalent to the number of phases. By contrast, the decrease of number of clusters leads to a phase association which reflects spectral affinities between phases. This result shows the existence of 6 to 7 vibrational bands in Mn oxides Raman spectra, with contrasting behaviours between clustering. Thereby, vibrational bands located in the low wave number domain (<510 cm−1) are more mobile and therefore more sensitive to structural modifications, while bands with higher wave number are less affected by structural changes. Besides these results, Raman responses collected during this study provide new refinement regarding the spectral content of some Mn oxides in particular todorokite, nsutite, and chalcophanite. Copyright © 2017 John Wiley & Sons, Ltd.

The study areas are located in the Katanga province to the South Eastern part of the Democratic Republic of Congo (DRC). It focuses on the Kolwezi and Tenke-Fungurume mining centers, located in the vicinity of the Basse-Kando reserve. The 3 study areas have faced large scale human induced the fragmentation of land cover. A combination of ancillary data and satellite imageries was interpreted to construct fragmentation dynamics over the last 30 years. This study is an initial step towards assessing the impact of fragmentation on sustainable land cover in the Katanga. The results bring out that large trends of fragmentation differently occurred over the last 30 years (1979 to 2011) in the three focused areas. The most dominant fragmentation processes were gains in barren soil and cities surface and a sharp reduction in burned areas. In Kolwezi, a close relationship is observed between growth and regression of barren soil and cities over vegetation. The Tenke-Fungurume site shows a growth during the 1980-1990 time slice and regression of vegetation during the following two decades. The Basse-Kando site analyze brings out growth of vegetation and regression of burned area due to vegetation conservation efforts. This is one of the studies in Katanga around mines activities that combine multi-source and spatio-temporal data on land cover to enable long-term quantification of land cover fragmentation.

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