Wiggles, Plateaus, and Precision: High-Resolution Radiocarbon Dating of the Transition from Early East Polynesian to Classic Māori Society.

Abstract

Achieving precise archaeological chronologies in island environments has long been hindered by plateaus and wiggles in the radiocarbon calibration curve. This study shows how to overcome these temporal bottlenecks by integrating Bayesian principles with high-precision sample selection, and demonstrates how the interpretation of archaeological context affects the results. Using two iconic Aotearoa, New Zealand sites previously dated over 30 years ago, we showcase the power of this approach and the limitations of working with legacy data. At Shag River Mouth, we reveal, for the first time, a detailed picture of site reuse starting ca. AD 1320 by considering changes ("wiggles") in atmospheric 14C between AD 1290 and 1400. Similarly, at Kokohuia, we demonstrate how to achieve greater resolution between AD 1480 and 1640, a plateau in the 14C calibration curve that has traditionally masked the transition between early East Polynesian and later Classic Māori culture. Our results provide unprecedented temporal resolution of economic changes over 500 years and demonstrate that these changes began much earlier than orthodox chronologies suggest.