<p>S4: ANOVA summary</p><p>Ns‡ Ls Np df * SS† MS† F† p† SS MS F p SS MS F p grinding G. subtapiroideum effect 1 1.47 1.47 0.12 0.735 36.67 36.67 4.50 0.063 3.30 3.30 0.28 0.611 facet Residuals 9 108.03 12.00 73.33 8.15 106.70 11.86 vs. G. steinheimense effect 1 146.06 146.06 3.20 0.087 100.74 100.74 2.11 0.160 7.09 7.09 0.14 0.715 shearing Residuals 22 1002.94 45.59 1049.26 47.69 1142.91 51.95 facet D. giganteum effect 1 416.50 416.50 4.68 0.038 165.44 165.44 1.70 0.201 860.03 860.03 11.41 0.002 Residuals 32 2849.00 89.03 3107.06 97.10 2411.97 75.37</p><p> species shearing facet effect 2 1841.61 920.81 14.89 <0.001 20.44 10.22 0.09 0.917 20.45 10.23 0.09 0.917 vs. Residuals 33 2041.39 61.86 3864.56 117.11 3863.55 117.08 species grinding facet effect 2 587.91 293.95 3.68 0.037 768.01 384.00 5.18 0.012 319.40 159.70 1.79 0.184 Residuals 30 2399.59 79.99 2223.99 74.13 2671.60 89.05 * Degree of freedom. † SS, sums of squares; MS, mean square, F: F-value, p: probability. ‡ Variables are abbreviated as follows: Ns, number of scratches; Ls, length of scratches (μm); Np, number of pits. S4: ANOVA summary (continued)</p><p>Nws Nlp df SS† MS† F† p† SS MS F p grinding G. subtapiroideum effect 1 15.49 15.49 1.50 0.252 0.83 0.83 0.07 0.800 facet Residuals 9 93.01 10.33 108.68 12.08 vs. G. steinheimense effect 1 70.53 70.53 1.58 0.222 7.09 7.09 0.14 0.715 shearing Residuals 22 981.47 44.61 1139.91 51.81 facet D. giganteum 1 152.47 152.47 1.62 0.212 265.44 265.44 2.83 0.102 Residuals 32 3005.53 93.92 3000.56 93.77</p><p> species shearing facet effect 2 617.67 308.83 3.33 0.048 1300.49 650.24 8.33 0.001 vs. Residuals 33 3056.83 92.63 2577.01 78.09 species grinding facet effect 2 29.10 14.55 0.16 0.856 303.68 151.84 1.71 0.199 Residuals 30 2797.90 93.26 2671.32 89.04 * Degree of freedom. † SS, sums of squares; MS, mean square, F: F-value, p: probability. ‡ Variables are abbreviated as follows: Nws, number of scratches (width > 15μm); Nlp, number of pits (major axis > 15μm). S4: ANOVA summary (continued)</p><p>Tot Pp df SS† MS† F† p† SS MS F p grinding G. subtapiroideum effect 1 5.87 5.87 0.51 0.494 1.47 1.47 0.12 0.735 facet Residuals 9 104.13 11.57 108.53 12.06 vs. G. steinheimense effect 1 63.82 63.82 1.29 0.268 9.44 9.44 0.18 0.674 shearing Residuals 22 1086.18 49.37 1140.56 51.84 facet D. giganteum effect 1 626.94 626.94 7.59 0.010 601.44 601.44 7.21 0.011 Residuals 32 2644.56 82.64 2671.06 83.47 Tot Pp df SS MS F p SS MS F p species shearing facet effect 2 117.14 58.57 0.51 0.603 713.99 357.00 3.72 0.035 vs. Residuals 33 3767.36 114.16 3171.01 96.09 species grinding facet effect 2 501.39 250.70 3.02 0.064 78.68 39.34 0.41 0.670 Residuals 30 2490.61 83.02 2913.32 97.11 * Degree of freedom. † SS, sums of squares; MS, mean square, F: F-value, p: probability. ‡ Variables are abbreviated as follows: Tot, total number of microwear features (Tot = Ns + Np); Pp, percentage of pits (Pp = 100*Np / Tot).</p>