Evidence of prehistoric Lapita diet at Watom Island, Papua New Guinea, using stable isotopes

Samples of human bone from six individuals from the Lapita burial ground at Reber-Rakival on Watom Island in New Britain were analysed for ð13C, ð15N and ð34S. The mean values obtained were–18.1, 11.6 and 9.9 respectively. From existing knowledge of isotope values, calorific content and protein yields for the main Pacific food types, computer simulation was used to randomly generate a large number of possible food compositions, in order to find the type of diet which could have produced the isotope pattern at Watom. The simulation produced solutions which are within acceptable limits of the Watom isotope signature. The mean food composition per day was then estimated as follows.