Extended Data Fig. 7: Further 3D surface model images of bone tools.

Illustrated in Fig. 3. These artefacts share similar techno-morphological features, in which the portion of long limb diaphysis closer to the epiphysis (where bones are thicker) is shaped into the tip of the tool, the base of the artefact is shaped in the portion near the metaphysis (thinner and with a more oval natural shape), and one lateral edge in the medial portion of the shaft is shaped into a deep notch. a, Massive tool made from the humerus of an elephant (accession number T79L10-9047; dimensions 375 × 93 × 105 mm). Series 1 (S#1-4): flake removals on the cortical aspect of the tip. Series 2 (S#5-8): sequence of alternating removals that indicates consecutive flipping of the blank. Series 3 (S#9-10): the cortical surface is used to strike flakes that are removed sequentially and clockwise. This series is truncated by (and hence is anterior to) the series starting with S#11. Series 4 (S#11-19): shaping of a crescent bottom at the base of the tool. Instead of wide and invasive removals such as those from the previous series, scars in Series 4 trim the edge to create a semicircular shape. Series 5 (S#20-29): unifacial removals from the cortical surface into the medullar side remove cancellous tissue and create a denticulate edge. Series 6 (S#30-34): a deep notch with several extractions within is created in the medial part of the edge. b, Unifacially-shaped bone tool (accession number T79L10-18461; dimensions 299 × 77 × 54 mm). Removals S#8-12 use scar S#1 as their percussion platform. Most of flaking is concentrated on one edge, where deep and invasive scars (S#3 and S#7) were succeeded by a contiguous sequence of flake removals aimed at creating a large notch (S#8-12) and shape the tip (S#13-16). Two V-shape scars (S#5-6) forming a dihedral angle at the tip run parallel to the tool axis are interpreted as fractures probably caused by percussive and compressive motions during tool use. Each scale bar segment, 1 cm. See additional details in Supplementary Videos 6 and 7.