Biogeochemical data from the Shamanka II Early Neolithic cemetery on southwest Baikal: Chronological and dietary patterns

Abstract

A data set of 116 AMS radiocarbon dates on human skeletal remains from an Early Neolithic (c. 7500–6700 cal BP) Shamanka II cemetery on Lake Baikal, Siberia, and associated carbon and nitrogen stable isotope values are analyzed for insights about site chronology and dietary variation of this group of hunter–gatherers. All dates are corrected for the Freshwater Reservoir Effect (FRE) according to the correction equations developed using paired radiocarbon dates on human and terrestrial faunal remains from the same graves (Bronk Ramsey et al., 2014; Schulting et al., 2014). Further examination of the data set provides the following main findings. First, it identified the presence of two phases of cemetery use at Shamanka II, each of quite different duration, separated by a relatively long period of disuse lasting as much as 300–550 years. Second, it demonstrated presence of four groups of people during the long Phase 1 each with a slightly different dietary pattern: three displaying a temporal change toward greater reliance on aquatic foods and one group, which apparently did not experience a diet shift. Third, the results show that all individuals from the short Phase 2 evince a clear chronological trend towards increased dietary contribution of aquatic food and that this pattern repeats closely one of the three trends present in Phase 1. While a generally similar chronological dietary trend has been found recently also among the Early Neolithic groups from the nearby Angara valley (Weber et al., 2015), the Shamanka II population appears to be much more diverse in dietary terms than its neighbours to the northeast.