Learning the lithic landscape: using raw material sources to investigate Pleistocene colonisation in the Ivane Valley, Papua New Guinea

Recent research in the Ivane Valley has shown that it was first occupied during the late Pleistocene between 43-49,000 years cal. BP, making this area one of the earliest colonised in Papua New Guinea. At an altitude of 2000 metres above sea level, occupation also marks the first time that modern humans pushed into the high altitude montane regions within Sahul. Part of the process of familiarisation with a landscape involves the identification of lithic sources. The importance of lithic sources for the landscape learning process is that, unlike plant foods and animals, it can be assumed that the colonisers had little a priori knowledge of their location before arriving in a particular landscape. If lithic sources are available, then their successful use would require a process of learning the locations and properties of the different raw material sources, thus creating an intimate level of knowledge of a landscape. By examining how modern humans familiarised themselves with the Ivane landscape through the use of lithic sources, we may be able to understand further the processes of colonisation and adaptation to particular landscapes. Keywords: colonisation, stone tools, raw material sources, Ivane, Papua New Guinea ********** New research in the Ivane valley (Summerhayes et al. 2010, 2009), located within the Owen Stanley Ranges of Papua New Guinea, has pushed back initial colonisation of this site to between 43,000-49,000 years cal. BP, placing it within the earliest stages of occupation of Papua New Guinea and thus Sahul. The significance of this early occupation is that, at almost 2000 metres above sea level, the Ivane valley is located within a high altitude environment, which during the late Pleistocene, was located close to the treeline, at a junction between montane forest and subalpine grasslands (Hope 2009). The colonisation of this valley marks the first time in the Sahul region that modem humans move into this type of high altitude environment. The importance of this occupation is that it may have required new adaptations to not only an unfamiliar landscape, but also to an unfamiliar habitat. This paper will examine the process of familiarisation with a landscape, what Rockman (2003) terms as "landscape learning", through examining how people both colonised and adapted to specific landscapes over time, using a geoarchaeological data set of lithic sources. With a subsistence technology involving the use of stone tools, the location and quality of these sources would have been important resources to initially identify. The importance of lithic sources for the landscape learning process is that, unlike plant foods and animals, it can be assumed that the colonisers had little a priori knowledge of their location before arriving in a particular landscape. If lithic sources are available within a landscape, then their successful use would require a process of learning the locations and properties of the different raw material sources, thus creating an intimate and detailed knowledge of a landscape. This familiarisation process may then provide further insights into the strategies used by modem humans to colonise and adapt to particular landscapes. Learning the lithic landscape The exploitation of new environments and habitats in Sahul suggests that changes in subsistence strategies will occur as modem humans become familiar with new resources such as plant foods and a marsupial fauna. Part of the process of changing the focus of subsistence strategies is learning the landscape; becoming more familiar with the specific resources available and how they can be used. Part of that landscape includes the lithic sources, which are only found at fixed locations, meaning that no previous knowledge of their location or qualities can be assumed prior to moving into a particular landscape. In order to use these sources successfully, a process of familiarisation of landscape must occur, where time is taken to locate and test different types of raw materials before selecting appropriate raw materials for use. …