Inland Pilbara archaeology: A study of variation in Aboriginal occupation over time and space on the Hamersley Plateau, Western Australia

In this thesis I describe the results of my analysis of archaeological material and sediments excavated from four rockshelters on the northeast Hamersley Plateau, Western Australia and synthesise previously reported archaeological evidence from the inland Pilbara to answer two questions about Aboriginal occupation. The first question asks how humans in the inland Pilbara responded to the Last Glacial Maximum (LGM) and compares their response to those of people in surrounding areas. Archaeological evidence from areas surrounding the inland Pilbara, such as the northwest coast, the interior and the Kimberley, indicate that people abandoned sites or used them less frequently during the LGM. A unique and significant feature of the inland Pilbara is the Hamersley Plateau, a massive plateau and escarpment feature that concentrates plateau runoff into long and deep gorges with aquifer-fed pools. Previously reported sites in the inland Pilbara are not near the escarpment and suggest abandonment or reduced frequency of use during the LGM, but I present new evidence from Milly's Cave, located near the escarpment, that indicates increased use during the LGM. This evidence indicates that the pliancy of hunter-gatherer adaptive systems during the LGM may have been underestimated and the local as well as regional environments are significant in understanding hunter-gatherer adaptations to climate change.

The second question asks what technological, economic and demographic changes occurred in the inland Pilbara during the middle and late Holocene and how these changes relate to those in surrounding areas. Located between the northwest coast and the interior, the inland Pilbara has been suggested to be a bridge for populations or ideas moving between the coast and the interior. New Holocene stone technologies appear at similar times in the Pilbara, northwest coast and interior, suggesting the three areas were part of regional systems of technological and economic change. Cultural changes associated with the new technologies are suggested by ethnographic information from the inland Pilbara that links the new technological types to ceremonial activities and gender-specific tasks. Archaeological evidence suggests that late Holocene increases in population dynamics in the inland Pilbara may be related to similar increases in the interior. This evidence suggests that there is a relationship between cultural, technological and economic change and population dynamics in hunter-gatherer populations.