Time and Relative Dimension in Space: Untangling site formation and taphonomic processes on archaeological shell from the tropical Indo-Pacific

Abstract

Understanding the formation and transformation of an archaeological site is imperative to creating robust inferences about human behaviour. Relatively little work has been undertaken on the varying anthropic and non-anthropic taphonomic processes that affect shell-bearing archaeological sites, particularly in tropical locations which are prone to extreme weathering and issues of long-term preservation. This thesis provides a greater comprehension of taphonomic processes impacting archaeological shell material and uses this understanding to untangle complex spatial and temporal aspects of an archaeological site in the Indo-Pacific. Two key areas of shell taphonomy include thermal influences, such as burning and heating, and acid dissolution. Experimental studies were undertaken on each of these processes and show variable results between taxa or microstructural type. Building upon these experiments, high-resolution taphonomic analyses of archaeological shell from Golo Cave, Gebe Island, Indonesia highlight taxon-specific patterning of various taphonomic processes (seen through varying physical traces) as well as overall trends in material deposition and preservation linked to human behaviours. The individual environmental conditions of this site also impact the types and intensity of taphonomic processes and thus the formation and transformation of the deposits. This is primarily seen through fragmentation rates, burning, physical abrasion, chemical dissolution, and bioerosion. Thermal influences have a distinct impact on the presence and degree of other taphonomic processes such as bioerosion and fragmentation, highlighting the connectivity between different processes. High-resolution analyses of shell midden from this site reveals periods of intensive occupation and changes in environmental conditions. Each shell tells a story, thus high-resolution taphonomic analyses provides a method to understand how different variables impact the formation and transformation of a site. This approach to shell analysis can provide a sharper understanding of the occupation of a site, particularly when stratigraphy does not provide a clear picture of site formation. It is through the examination of pre- and post-depositional taphonomic processes that archaeologists can create robust inferences about human behaviour, hence the importance of discerning the effects of varying processes on shell material.