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

Fiona Petchey; Atholl Anderson; Louise Furey; Simon Bickler; Gerard O'Regan; Matthew Schmidt; Roderick Wallace; Peter Sheppard

doi:10.70460/jpa.v16i1.412

Authors

Fiona Petchey Waikato University https://orcid.org/0000-0002-3308-9983
Atholl Anderson Australian National University https://orcid.org/0000-0002-7636-7306
Louise Furey Indipendent scholar
Simon H Bickler University of Waikato https://orcid.org/0000-0001-7620-2862
Gerard O'Regan Tuhura Otago Museum
Matthew Schmidt Department of Conservation https://orcid.org/0009-0001-5865-4723
Roderick Wallace Independent scholar
Peter Sheppard University of Auckland https://orcid.org/0000-0001-6624-7856

DOI:

https://doi.org/10.70460/jpa.v16i1.412

Keywords:

Bayesian analysis, calibration wiggles and plateaus, East Polynesian Settlement, Maori cultural transition

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.

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