Abstract
Shell valuable exchange in the New Guinea Highlands has been a key interest in anthropology, providing insight into economics, aesthetics, and social stratification among banded communities. This article describes how shell exchange at ethnographic present reflects deeper historical processes. We trace the origins and subsequent changes in shell use from the terminal Pleistocene to the Late Holocene at the site of Kiowa in Chimbu Province, Papua New Guinea. Zooarchaeological and technological analyses of Kiowa's shell artifacts indicates riverine mussel was procured locally from the terminal Pleistocene (9,500-10,000 years ago) and featured as a minor component in the diet into the recent precolonial period. In contrast, evidence for marine shell valuables only appears in the Late Holocene in the form of Trochus armbands and Tegillarca granosa and Polymesoda cf. erosa multifunctional tools. This challenges ideas that associate the gradual dispersal of marine shell into the highlands with the spread of agriculture around the Wahgi Valley at the start of the Holocene and supports punctuated pulses of coastal contact. In doing so, we formulate a testable model for the development of shell exchange into the highlands, with implications for the emergence of stratification and the conduits between the interior and coast.