Collagen δ2H (‰) and δ18O (‰) by species and site, with numbers corresponding to site locations in Fig. 1, with sites Los Berrocales in Spain (1) and Megiddo in Israel (5). The error bar corresponds to our laboratory’s long term reproducibility (1 sd of long term mean, n = 80 for δ2H, n = 161 for δ18O). Horizontal bars indicate no significant differences between groups (p > 0.05, Tukey’s Honest Significant Differences, Table S2); there are fewer significant differences between groups in δ18O values than δ2H values. Cattle δ2H are significantly different by site for all three pairwise comparisons (Table S2).