02423nas a2200229 4500008004100000245011400041210006900155260001200224300001000236490000600246520171100252653003001963653000901993653003302002653002302035653002302058100001702081700002002098700001702118700002102135856003702156 2019 eng d00aFreshwater reservoir offsets on radiocarbon-dated dog bone from the headwaters of the St. Lawrence River, USA0 aFreshwater reservoir offsets on radiocarbondated dog bone from t c06/2019 ae71740 v73 a

Isotopic analysis of dog (Canis lupus familiaris) bone recovered from archaeological sites as proxies for human bone is becoming common in North America. Chronological placement of the dogs is often determined through radiocarbon dating of dog bone. The Great Lakes, their tributaries, and nearby lakes and streams were important fisheries for Native Americans prior to and after sustained European presence in the region. Carbon entering the food web in freshwater systems is often not in full isotopic equilibrium with the atmosphere, giving rise to spuriously old radiocarbon ages in fish, other aquatic organisms, and their consumers. These freshwater reservoir offsets (FROs) have been noted on human and dog bone in several areas of the world. Here we report the results of multi-tracer Bayesian dietary modeling using δ15N and δ13C values on dog bone collagen from mid-fifteenth to mid-sixteenth-century Iroquoian village sites at the headwaters of the St. Lawrence River, New York, USA. Results indicate that fish was an important component of dog diets. 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 14Cyr with a weighted mean of 132 ± 8 14Cyr. 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.

10aBayesian dietary modeling10aDogs10aFreshwater reservoir offsets10aradiocarbon dating10aSt. Lawrence River1 aHart, J., P.1 aFeranec, R., S.1 aAbel, T., J.1 aVavrasek, J., L. uhttps://peerj.com/articles/7174/