Reservoir effect radiocarbon dating
A comparison of radiocarbon dates on dog bone with dates on deer bone or maize from the same sites indicate FROs ranging from 97 ± 24 to 220 ± 39 14 Cyr with a weighted mean of 132 ± 8 14 Cyr.
These results suggest that dog bone should not be used for radiocarbon dating in the absence of modeling to determine fish consumption and that previously reported radiocarbon dates on human bone from the larger region are likely to have FROs given the known importance of fish in regional human diets.
Variations in these apparent reservoir effects presumably result largely from the interplay of differential ocean water upwelling and customary faunal feeding areas, although possible effects of other species characteristics cannot be ruled out.
Dating of marine samples from the Bering Sea should thus either proceed with the expectation that age determinations may not be accurate within several centuries, or be approached through experimental measurement of reservoir effect among restricted faunal species in limited areas.
Differences from within each of 14 pairs of wood charcoal vs. Lawrence Island, Cape Prince of Wales, Nunivak Island, Alaska Peninsula, and Unalaska Island) yield a weighted mean of 737 ± 20 years.
Somewhat more variant differences from within each of five additional pairs of wood charcoal vs. Lawrence Island, Unalaska Island) provide a lower weighted mean of 460 ± 41 years.
The marine reservoir effect is known to skew radiocarbon dating (marine samples appear “older ” than terrestrial samples of equivalent age), but the magnitude of this effect is not the same in all locations.
We report here on a comprehensive radiocarbon dating program to date the age of the Kwädąy Dän Ts’ìnchį man.