Search for: All records

The middle-late Holocene in Southern Belize saw shifts in subsistence strategies including the introduction of managed plants and animals. Botanical and stable isotopic data have been used to track the introduction of agricultural products into diet with maize first consumed before 7,000 cal. BP. However, the timing of the introduction of managed animals is less understood because early faunal assemblages are rare. Carbon isotope (d13C) analysis of amino acids (CSIA-AA) is a powerful tool that allows researchers to track biochemical origins of individual amino acids into consumer tissues. CSIA-AA analysis of directly dated human skeletons from two rockshelters spanning the transition to agriculture show a trend of increasing d13Clysine values indicating a C4 lysine origin in individuals by the Classic Maya period. Additionally, individuals that date to the middle Holocene demonstrate higher than expected incorporation of C4-derived lysine. Based on the low abundance of lysine in maize (C4-plant) and daily lysine requirements in humans, these results are only possible through trophic concentration of C4-derived lysine, obtained by consuming maize-eating animals. We propose that human d13Clysine values can be used to track the incorporation of managed, but not necessarily domesticated, animals into neotropical diets during the transition to agriculture.