Fig 1.
Location and map of La Roche-Cotard.
A and B. Geographical and geological location of La Roche-Cotard. C. Map of the main Mousterian sites in central-west France. Sources: geological map redrawn from BRGM; coastlines, relief and rivers: Natural Earth (public domain); Map of France: reprinted from d_maps.com under a CC BY license, with permission from d_maps.com. Maps made with QGIS 3.4.12-Madeira (H. Guillemot).
Fig 2.
A. Map of La Roche-Cotard with its four loci: LRC I, LRC II, LRC III and LRC IV. In blue: location of anthropogenic marks. B. Profiles of slope sections (red lines in A) with location of sediments extracted in 1846.
Fig 3.
Lidar survey of the site of La Roche-Cotard.
Orthophoto. The Lidar image shows the 1846 exploited zone and the cave (LRC I) in white. The cave entrance is in the abrupt northern slope left by workers in 1846. A Lidar drone survey was carried out on the area surrounding the cave using a Yellowscan Mapper, mounted on a Matrice 300 with three passes at a height of 35 m. These scans were then assembled using Yellowscan software. A Digital Terrain Model was generated at 10 cm resolution from these data, along with a hillshade version and contour lines. (Lidar ICONEM).
Fig 4.
Description of La Roche-Cotard Cave (locus LRC I).
A. Lithological map of the cave floor. B. XY section in the Pillar and Lemmings Chambers (location in A). The elevation of the ground surface increases steeply from the entrance to the Lemmings Chamber, and then only very slightly from SE to NW till the Hyena Chamber (1.5 m). 95% of the sediments that occupied a large part of the cave were removed during the 1912 excavation. Layers to the SE: Middle layer (b), Upper layer (a), Disturbed layer (r). Layers to the NW: Compact clayey layer with tuff gravel with bone fragments and coprolites (3). Sandy layer with soft reddish clay pebbles (4). Disturbed layers: (1), (2) and (r). The three arrows show the place of the overhang (50.75 m NGF, Nivellement Général de la France: general levelling of France) extending from the entrance of the cave to the Pillar Chamber.
Fig 5.
Lithostratigraphy and geometric distribution of the superficial deposits outside the cave.
(A). Block diagram with loci positions and in particular the sub-loci LRC I-a to d. The stratigraphy of the layers intersected by LRC II (B), LRC III (C) and LRC IV (D). For each locus, the stratigraphic units (U5/red, U4/blue, U3/brown, U2/orange, U1/green) and their vertical extension is indicated. Each unit comprises several layers.
Fig 6.
Location of undisturbed deposits near the LRC I cave entrance.
The map locates the two orthophotos in the centre of the figure. The entrance of the cave, on the left orthophoto, is underlined in black. The dashed horizontal line corresponds to the altitude of the overhang to the pillar room as well as to the lower limit of the ceiling of the cave entrance. Below, the LRC II photograph shows only the upper part of the stratigraphy of this locus (Fig 5B), marking the period when sediments began to deposit on the slope. On the left, LRCI-a (Fig 5A) shows the middle and upper layers inside and outside the cave. Bottom right, LRCI-b (Fig 5A) also illustrates the same middle layer as found in LRCI-niches 1 and 2, but inside the cave entrance. LRCI-c (Fig 5A) shows the location of sediment remnants trapped in ancient and small galleries created by erosion in the hard cretaceous stone, belonging to the deposit which completed the sealing of the entrance. LRCI-d shows sediments very similar to those of LRCI-c (Fig 5A) which continued to accumulate for some time after the cave was closed. Altitudes are given to clarify the location of these different sections. The lower view of LRC I-niche 2 is from 1975 (Photogrammetry Iconem).
Fig 7.
Reconstruction by 3D rendering of the slope of the site at different time periods.
A: the diagram shows the state from 1846 till today (photogrammetry based on drone images); B: the slope before quarring in 1846; C: the site during the Neanderthal frequentations. Excavations (at LRC I, LRC II, LRC III and LRC IV) always showed sediments in direct contact with the tuff. The entrance to the cave was probably the same as today. At LRC II, the human settlement was located on the surface of a small bank of the Loire, a few meters below the entrance to LRC I. The cherty roofs of LRC III and IV are continuous, and the presence of anthropic layers makes it possible to trace the shape of the wall when these four spaces were occupied, but it is not possible to know in what chronological order the occupations took place. The Loire was then found close to the foot of the slope and carried downstream the sediments arriving from the plateau during a long period (Drone photos by J.-P. Corbellini from MSH Val de Loire. 3D model by N. Nony).
Table 1.
Archaeological material found in LRC I (cave).
Fig 8.
Morphometric discrimination of wall marks.
A. Linear discriminant analysis of widths, incision angles and depth of marks on the wall of LRC I cave. “TRI”: Triangular Panel, “CIR”: Circular Panel, “REC”: Rectangular Panel, “CLA”: claw marks surface. S7 Fig gives elements showing how measurements have been made. B. Linear discriminant analysis of widths, incision angles and depth of experimentally created marks on the Turonian yellow tuff wall of a pilot cave. Marks made with finger: “FING”, with bone: “BONE”, with wood: “WOOV”, with antler: “WOOA” and with flint: “FLIN”. S7 Fig shows example results of modern engraving. C. Photograph of a cave wall in LRC I. Modern marks (green arrows), located on the Dotted Panel (traces 27–35), are attributed to the excavation of the cave in 1912. Red arrows point to marks believed to be old, and blue arrows to the surface of the wall coating. D. Table of determinations of Munsell Soil-Color Chart for colours depicted on the three surface categories pointed in (C). E. LDA processing of 99 marks using L* a* b* colour parameters, 45 for Brown coating (RB), 44 for Finger impacts (TD) and 10 for Modern marks (TM).
Table 2.
Measures of width, incision angles and depth of the parietal and experimental marks.
Table 3.
Measures given by spectrocolorimeter on the wall coating, anthropogenic and modern marks.
Fig 9.
Spatial organisation of the marked panels in the Pillar Chamber.
A. View of the Pillar Chamber from the entrance, showing the location of panels with markings. Sections and ridges of the ceiling are indicated by red lines. Numbered panels are indicated by blue areas or arrows. The horizontal grey area on the ground is at the altitude (50.05 m NGF) of the top of the very compact layer 3, in front of the last five digital trace panels. B. Orthophoto of the north-west and north-east walls of the Pillar Chamber, with the location of the panels with plots. The dashed line represents the probable ground level. a: Entrance Panel; b: Fossil Panel; c: Linear Panel; d: Undulated Panel; e: Circular Panel; f: Triangular Panel; g: Rectangular Panel; h: Dotted Panel (Photogrammetry Y. Egels).
Fig 10.
The limits of the finger flutings are shown in black. When the edges are well cut, the line is thicker. When the line is not clearly legible, the line is dashed. Animal tracks are in blue. This legend also applies to all other panels. The survey (J. Esquerre and H. Lombard) gives the numbering of the traces.
Fig 11.
The survey (O. Spaey and G. Alain) gives the traces numbering. The arrows indicate the direction of the passage of the finger.
Fig 12.
The survey (O. Spaey and G. Alain) gives the numbering of the traces. The arrows indicate the direction of the traces. The alteration of the central lower part is very strong and worrying. S11 Fig shows the Undulated Panel and the Circular Panel together.
Fig 13.
The survey (M. Calligaro) gives the numbering of the traces. The green zone corresponds to the surface of the break of a natural cylinder of chert in its natural place. There are complements in S12 Fig about that panel.
Fig 14.
The survey (O. Spaey and G. Alain) gives the numbering of the traces. Animal marks are in blue. Traces 13 to 15 and 27 to 35 are modern anthropic traces made with metal tool.
Table 4.
14C ages.
Table 5.
Summary of multi-grain quartz (Q) OSL results.
Fig 15.
Schematic drawing of LRC I and LRC II lithographic section and multi-grain quartz ages from units 1–4.
A Bayesian model (Bacon script [89]) using the elevation as prior and only random uncertainties for the individual ages is shown (black line). Dotted lines show the total uncertainty (including both random and systematic uncertainties) at the 68% confidence interval. The OSL ages measured in Hungary are not included in the Bayesian model. The dashed black horizontal line indicates the cave ceiling elevation in LRC I (50.75 m). The insert shows LRC I-a (see Fig 6) including two samples inside the cave (167805 and -06) and two outside the cave (187311 and -12). LRC I-d includes three samples on a trench on the slope, on top of the cave. The adopted water content is 40±10% of the average measured saturated water content for each deposition unit.
Fig 16.
Schematic drawing of LRC IV lithographic section and multi-grain quartz ages from unit 1, 2 and 4.
The bottom two samples (167819, 167820) are shown on the diagram but not included in the Bayesian fit (using only random uncertainties; black full line, see S2 Text for further details). Dotted black lines show the total uncertainty (including systematics) of the age model. Uncertainties shown on each data point are at 68% confidence. A water content of 40±10% of the average saturated water content for each deposition unit has been assumed.
Fig 17.
Average limiting ages derived from Bayesian modelled of multi-grain quartz OSL ages using elevation limits for LRC I and II (red lines) and IV (blue lines).
The uncertainty (68% confidence level) of these ages is shown with black error bars. The minimum and maximum ages in each unit and in the Mousterian levels are indicated with vertical black dotted lines. For unit 5 (n = 4 samples), the lower age range is derived from sample 187304. No upper age limit is given for this unit as other samples in unit 5 were in saturation. Marine isotope stages 1–7 (MIS) are indicated as red and blue vertical bands (top x-axis). The vertical dashed line indicates the minimum age of the cave entrance closure.
Fig 18.
The chronological position of La Roche-Cotard in comparison with other sites yielding artefacts of a symbolic nature.
The curve [100] indicates climatic variations from 200 ka to the present (x-axis); on the y-axis, in degree Celsius, the difference in the average temperature between a given period and today is indicated. Eg = Earlyglacial, MPg = Middle Pleniglacial, UPg = Upper Pleniglacial, Lg = Lateglacial, MIS = Marine Isotope Stage. Yellow and red colors indicate the presence of Homo neanderthalensis and Homo sapiens. The caves of Chauvet, Lascaux, Roc de Marsal, Le Régourdou and Bruniquel are in France, Altamira Maltravieso, La Pasiega, Ardales and Los Aviones are in Spain, Gorham in Gibraltar, Qafzeh, Tabun and Skhul are in Israel, Border Cave and Blombos are in South Africa. EMSA = Early Middle Stone Age, LMSA = Late Middle Stone Age, LSA = Late Stone Age, EMP = Early Middle Palaeolithic, LMP = Late Middle Palaeolithic, UP = Upper Palaeolithic.