Hypotheses to explain the few early coastal archaeological deposits in Sāmoa: Preliminary evaluations

Abstract

The Remote Oceanic archipelagos from Vanuatu to Sāmoa were first occupied 3000 years ago by populations with Lapita pottery at over 100 colonization sites. In Sāmoa, however, the first millennium of settlement is comprised of only a few isolated archaeological sites, and only one with Lapita pottery. This unique archaeological record is typically explained as a result of isostatic subsidence that destroyed or displaced more numerous coastal colonization sites. Three additional hypotheses may account for this pattern. First, few coastal flats may have existed for settlement, limiting occupation of the archipelago. Second, terrestrial geological processes may have destroyed what were once more numerous sites. Third, the few early and isolated sites in Sāmoa may reflect a small population of colonists resulting from demographic processes, including wave-front population density, or the Allee effect. We conducted a preliminary examination of the first two alternative hypotheses through a programme of coring and excavation across three coastlines on ‘Upolu island, Sāmoa. Sub-surface sediment data suggest both hypotheses may be valid explanations in different coastal settings. We propose additional research to test this possibility.