Using bone fragmentation records to investigate coastal human ecodynamics: A case study from Čḯxwicən (Washington State, USA)

Abstract

Coastal shell middens are known for their generally excellent preservation and abundant identifiable faunal remains, including delicate fish and bird bones that are often rare or poorly preserved at non-shell midden sites. Thus, when we began our human ecodynamics research project focused on the fauna from Čḯxwicən (45CA523, pronounced ch-WHEET-son), a large ancestral village of the Lower Elwha Klallam Tribe, located on the shore of the Strait of Juan de Fuca, Port Angeles, Washington (USA), we anticipated generally high levels of bone identifiability. We quickly realized that the mammal bones were more fragmented and less identifiable than we had expected, though this was not the case with the bird and fish bone or invertebrate remains. To better understand why this fragmentation occurred at Čḯxwicən, we evaluate numerous hypotheses, including both post-depositional and behavioral explanations. We conclude that multiple factors intersected (to varying degrees) to produce the extreme bone fragmentation and low identifiability of mammal bones at the site, including bone fuel use, marrow extraction, grease rendering, tool production, and post-depositional breakdown. Using a human ecodynamics framework, we further consider how both social factors and external environmental forces may mediate human choices, such as the economic decision to use bone for fuel or render bone grease. We place our findings from Čḯxwicən in a regional context and discuss the potential of the approach for other coastal archaeological sites worldwide.