Fig 1.
Geographic situation of the BL site.
1a. View of the current landscape configuration in which the BL site is located (Photo: F.L. Chmiel). The BL site (on the left) was near to the edge of the paleo-lake, and is situated today on the edge of a ravine with a N-S direction. 1b. General view of the BL site. 1c. Geographic position of some circum-Mediterranean sites in Eurasia that have yielded Oldowan lithic assemblages with (yellow dot and underlined in the text) or without PSSB morphologies indicated by bibliography. (USGS National Map Viewer).—Circum-Mediterranean Oldowan sites in Eurasia with and without polyhedral/subspheroid morphologies: (1.) BL and FN 3 (1.4 and 1.2 Ma., Andalusia, Spain); (3.) Levels TD6 Gran Dolina (0.8–0.9 Ma.) [95, 96, 97], and TE9 at Sima del Elefante, Atapuerca (1.2 Ma, Castilla y León, Spain) [98, 99]; (4.) Vallparadís (ca. 0.98 Ma, Catalonia, Spain) [83, 100]; (6.) Pont de Lavaud (1,1 Ma., Indre, France) [99, 101]; (7.) Le Vallonnet (ca. 1.2 Ma., Roquebrune-Cap-Martin, France) [102, 103]; (8.) Ca’ Belvedere di Monte Poggiolo (ca. 1 Ma., Emilia Romagna, Italy) [104, 105, 106, 107]; (9.) P13 locality of Pirro Nord (1.6–1.3 Ma., Puglia, Italy) [108, 109, 110, 111]; (11.) Bizat Ruhama (Israel, 1.6–1.2 Ma) [112]; (12.) In North Africa, Ain Hanech (ca. 1.8 Ma, Algeria) [42, 113]; (13.) and Ain Boucherit (ca. 1.9 and 2.4 Ma, Algeria) [114]; (14.) Dmanisi (1.85–1.78 Ma., Georgia) [115, 116, 117].—Circum-Mediterranean Acheulian sites in Eurasia with polyhedral/subspheroidal tool morphologies: (2.) Santa Ana cave (ca. 117–183 Ka. BP, Extremadura, Spain) [118]; (5.) US4 Bois-de-Riquet site (ca. 0.8 Ma.), Lezignan-la-Cèbe, Herault, France) [119]; (10.) and ‘Ubeidiya (1.6–1.2 Ma, Israel) [120, 121, 122].
Table 1.
Frequency of the different structural categories composing the lithic assemblage from BL.
Fig 2.
Polyhedral and subspheroid morphotypes from the BL site (a-e), and multidirectional cores selected for the diacritical analysis (f-g).
Specimen: Tool a: BL.2014.D2.G49.114; Tool b: BL.2014.D2.M49.49; Tool c: BL.2002.D1.N55.580; Tool d: BL.2002.D1.M54.500; Tool e: BL.2018.D1.N41.1; Tool f: BL.2002.D1.J52.69; Tool g: BL.2003.D1.I53.27. Stored at the Archaeological and Ethnological Museum of Granada (Spain). All necessary permits were obtained for the described study, which complied with all relevant regulations.
Fig 3.
Different degrees of alteration.
(left) Level 1: Not altered; (center left) Level 2: Slightly altered; (center right) Level 3: Altered; (right) Level 4: Very altered (Photos: S. Titton).
Fig 4.
Graphic representation of the methodology used for the diacritical drawings of the polyhedral/subspheroid lithic tools from BL.
Impact points and negative directions are indicated and the different reduction phases are highlighted by different colors.
Fig 5.
Graphic representation of the diacritical methodology used to interpret the polyhedral/subspheroid lithic tools from BL.
The different colors of the negatives represent the different phases of reduction.
Fig 6.
Representative images of angles detection.
1a) Example of angles measured between the facets; 1b) In order to determine the percussion angle, only the corners displaying an impact point are taken into account; 2) Example of angle detection used for trigonometric calculation.
Table 2.
General morpho-technical characteristics of the analyzed multifacial multifaceted tool sample from BL.
Fig 7.
Photo and diacritical drawing of Tool D.
Phase 1 (green) creation of a percussion platform (Profile A). Phase 2, (yellow) Platform negatives transected orthogonally, as the piece was peripherally knapped (Profiles B and E). Phase 3 (blue): Series of removals from a cortical platform (Profile D), cutting the structure transversely (Phase 2) and frontally (Phase 1). The use of the bipolar-on-anvil technique is observed (in particular on Profile B) (see negative 5 * and 6 * in contrast to negative 7 *), with some negatives probably resulting from anvil repercussion (ie. negative 7*). Traces of percussion (Fr. piquetage) are observed on the cortical surface (Profile C—circle).
Fig 8.
Photo and diacritic drawing of Tool E.
Phase 1 (in green): Creation of a platform (Profile B) by a removal or a previous phase of partial peripheral management of the tool (Profile E and F, green); Phase 2: (yellow). A series of peripheral extractions 4 *, 5a, 5b, 5c, 6, 7, 8 (Profiles A, C, E and F) from percussion platform created by negative 1* (Profile B) partially effaces the Phase 1 negatives. Phase 3 (blue), oblique removals contribute to lending a rounded morphology to the tool (Profiles C and D).
Fig 9.
Photo and diacritical drawing of Tool F.
Phase 1 (green): Peripheral removals (Profiles D) and creation of the main knapping platform (Profile A). Phase 2a (light yellow): a Siret flake (negative 5, Profiles A and D) was obtained obliquely, creating a contact area separating the two surfaces defined in Phase 1. Phase 2b (dark yellow): a new series of parallel, peripheral removals was made, departing from the platforms defined in Phases 1 and 2a (Profiles B and E) (between them Phase 1 and Phase 2a). Phase 3 (light blue): the cobble was rotated to knap a few flakes that cut into the surface of the Phase 2b negatives. Phase 4 (dark blue): retouching from the Phase 1 platform overlaps the Phase 2b negatives.
Fig 10.
Photo and diacritical drawing of Tool G.
Phase 1 (green): creation of the percussion platform (Profile A). Phase 2 (yellow): recurrent knapping series of flakes using orthogonal method from Phase 1 platform. Phase 3 (light blue): Tool rotation and small removals from cortical surface cutting previous negatives of Phases 1 and 2. A last phase (use) corresponds to accidental removals (purple), on convergent cortical surfaces and on Phase 2, due to percussion activity.
Fig 11.
Photo and diacritical drawing of Tool C.
Phase 1 (indicated in yellow): A single phase of core management (or possibly configuration). Phase 2 (indicated in purple): the tool’s protruding crests were used for pounding activity.
Fig 12.
Comparison of the diacritical drawings and simplified operative scheme deduced from the diacritical lecture (cube on bottom right).
Fig 13.
Boxplot underlining the dual tendency of the pieces.
Group A (Tools A, C, F and G) compared to Group B (Tools B, D and E).
Table 3.
Univariate statistics of the different tools from BL site.
Fig 14.
Percussion marks on the analyzed tool sample.
a.) Micro-removals; b.) Surface scarring; c.) Cupola; d.) Accidental removal negatives; e.) Facetted breakage.
Table 4.
Sites with PSSB morphologies divided by geographic zone and Oldowan or Early Acheulian techno-complexes.
Oldowan or Early Acheulian techno-complexes with PSSB morphologies [13, 16, 31, 34, 36, 37, 38, 41, 42, 46, 51, 104, 105, 107, 118, 119, 120, 125, 136, 139, 141, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175].