ABSTRACT
The second step is to reconstruct the isotopic composition of the human diet from that of the human bone. The relationship between diet δ13Cd and collagen δ13Cco is variable, making collagen δ13Cco an unreliable indicator of overall diet. Apatite carbonate δ13Cca values in laboratory animals fed controlled diets, however, are consistently spaced at a 9.50‰ interval from that of the diet (Ambrose & Norr, 1993). Following this experimental model, diet δ13Cd values can be obtained by subtracting 9.50‰ from the bone apatite carbonate δ13Cca values. The ∆15N diet-to-collagen spacing of 2.50‰ (DeNiro & Epstein, 1981) was used to determine the diet δ15N from human bone collagen δ15N (collagen δ15N less 2.50‰). The error bars in Figure 10.2 represent two standard deviations from the means of the Tutu human diet.
