Stable isotope evidence of human diet at the Nukdo shell midden site, South Korea

Carbon and nitrogen stable isotope analysis was undertaken on bone collagen extracted from archaeological human (n = 48) and animal (n = 45) skeletons from the Nukdo site, Location I C, South Korea. This shell midden and grave site is dated from the late Mumun (550–300 BC) to early Iron Age (300 BC-1 AD) periods. The herbivorous mammals fell within the range of C3 consumers, with average values of δ13C = −21.0 ± 0.5‰ and δ15N = 3.6 ± 0.5‰ for deer (n = 16) and δ13C = −20.6 ± 0.5‰ and δ15N = 4.5 ± 2.0‰ for wild boar (n = 17). Humans from this site averaged δ13C = −18.3 ± 0.4‰ and δ15N = 11.2 ± 0.7‰ for adults (n = 15) and δ13C = −18.7 ± 0.7‰ and δ15N = 12.5 ± 1.1‰ for juveniles (n = 33). These δ13C values indicate that there was no significant input of C4 plants in the human diets and this may be associated with the spread of rice agriculture in the Mumun period. Human bone collagen δ13C and δ15N values indicate that there was some consumption of marine foods, although the main protein sources were from terrestrial foods. The isotope data demonstrate that the humans at Nukdo had mixed diets that included marine and terrestrial protein, including C3 plants such as rice. Finally, the isotope results from the juveniles indicate that weaning occurred before the age of 1.5 years in this period.