Bayesian analysis of the chronology of the Lynch site (25BD1) and comparisons to the Central Plains Tradition and Central Plains Oneota

Abstract

This paper presents a series of new radiocarbon dates on the Lynch site (25BD1), an Initial Coalescent site in northeastern Nebraska, and takes a Bayesian approach to examining them in three contexts. First, we consider what they tell us about the chronology of occupation at the site itself. Second, we combine them with dates on other sites in the Ponca Creek drainage to consider the chronological pattern of horticultural settlement there. Finally, we compare the Ponca Creek dates to the radiocarbon chronologies for the Central Plains tradition and Central Plains Oneota. Our analysis indicates that people settled Lynch from east to west and abandoned it from west to east between roughly AD 1250 and 1350. At its maximum extent, farmers appear to have occupied the full 80 ha extent of the site. As farmers settled Lynch, closely related people settled upstream on Ponca Creek. People abandoned these communities shortly before they abandoned Lynch. Farmers settled on Ponca Creek as a whole shortly after the major expansion of Central Plains tradition (CPt) ways of life and the appearance of Central Plains Oneota towns and abandoned that area a generation or two before CPt communities disappeared. Central Plains Oneota communities persisted into the mid 1400s. The Lynch/Ponca Creek pattern is consistent with the movement of Central Plains populations into the southern portion of the Middle Missouri in the early 1300s.