Earliest Evidence for Pit Cultivation Provides Insight on the Nature of First Polynesian Settlement

Abstract

First Polynesian settlement by Lapita peoples occurred ca 2850 cal BP at Nukuleka, then a small sandy islet at the entrance to the lagoon on the island of Tongatapu, Kingdom of Tonga. Recent studies document the presence of a planting pit here where, with interception of the Ghyben-Herzberg freshwater lens and use of organic mulch, aroids could be grown. Original pit excavation is dated to first landfall or shortly thereafter. Dates further indicate the pit was filled between 2690 and 2390 cal BP. The saturated mulch, combined with coralline sand in the pit-bottom, resulted in a gray-brown silty-sand planting matrix. Microfossil analysis of these sediments have identified Oceanic cultigens, including giant swamp taro (Cyrtosperma merkusii), taro (Colocasia esculenta), banana (Musa sp.), candle nut (Aleurites moluccana), pandanus (Pandanus tectorius), and coconut (Cocos nucifera). Also present in the matrix are large numbers of Lapita ceramic sherds, these probably added for moisture retention and, possibly, nutrients as they degrade. The planting pit is the earliest recorded evidence for this type of cultivation in Oceania. It illustrates an ingenious exploration strategy for Lapita peoples that is well adapted to most types of islands they would encounter.