35,000-Year-Old Sites in the Rainforests of West New Britain, Papua New Guinea

Article excerpt

The growing story of early settlement in the northwest Pacific islands is moving from coastal sites into the rainforest. Evidence of Pleistocene cultural layers have been discovered in open-site excavations at Yombon, an area containing shifting hamlets, in West New Britain's interior tropical rainforest. These sites, the oldest in New Britain, may presently stand as the oldest open sites discovered in rainforest anywhere in the world.

Introduction

This note presents new Pleistocene dates from the island of New Britain, Papua New Guinea. Recent research at Yombon has revealed cultural deposits dating from 35,000 b.p. Previous archaeological work in West New Britain succeeded in revealing only terminal Pleistocene occupation (Specht et al. 1983). The new dates from Yombon extend the human occupation of West New Britain by 23,000 years, making them equivalent in age to the earliest sites in neighbouring New Ireland (Allen et al. 1988). While the 40,000 year old dates from the Huon Terraces in Papua New Guinea remain the earliest evidence of human occupation in coastal forest in this region (Groube et al. 1986; Groube 1989) the sites at Yombon are important because they indicate the use of inland forest environments and resources, including sources of high-quality chert, from the Pleistocene to the present. These data also run counter to claims that rainforest environments were only occupied for the first time in the late Holocene.

Prior to the discoveries at Yombon, the earliest Pleistocene sites in the Bismarck Archipelago were coastal caves (Allen et al. 1988; Wickler and Spriggs 1988). These sites have revealed the early spread of humans into island Melanesia and the marine adaptations necessary. Similarly, evidence of early colonisation of the high altitude mid- and upper-montane forest of interior Papua New Guinea indicates the penetration and manipulation of these environments by at least 30,000 b.p. (White et al. 1970; Gillieson & Mountain 1983). No evidence exists, however, for the utilization of the lowland forests. The sites at Yombon provide new evidence that lowland forested areas were used during the late Pleistocene and early Holocene.

The fact that we have found only a small number of sites and artefacts dated to the Pleistocene is unremarkable. In these tropical regions, high rainfall and such activities as forests clearance and gardening can result in high rates of erosion and extensive surface alterations which greatly diminish the possibility of in situ archaeological deposits of such antiquity. The discovery of Pleistocene cultural deposits in trenches over half a kilometre apart, all yielding similar radiocarbon determinations and stratigraphic sequences, makes us confident that they are in situ Pleistocene assemblages. This confidence is increased by the overall structure of the sites which give a consistent stratigraphic picture over a wide area (Pavlides 1993). The local topography of this part of West New Britain with its limestone ridges and valleys, coupled with the deposition of airfall tephras, are undoubtedly the key factors in preserving small patches of Pleistocene activities. In every trench containing remnants of the old tephra there were underlying Pleistocene deposits, possibly demonstrating taphonomic processes at work rather than low levels of human activities, which originally may have been much more widespread in this area. Specht (et al. 1981) positioned his excavations at Yombon on the plateaux rather than the valley bottoms, where these new sites occur, and failed to locate any deposits older than 4000 b.p. These data must also alert us to the fact that rainforest occupation in New Britain may have been widespread during the late Pleistocene.

The sites at Yombon are composed of a series of chemically distinct tephras which can be traced over large areas of the forest. These tephra layers provide the opportunity to look not just at individual sites but at whole landscapes, e. …