Functional studies of flaked and ground stone artefacts reveal starchy tree nut and root exploitation in mid-Holocene highland New Guinea

Abstract

Ground stone technology for processing starchy plant foods has its origins in the late Pleistocene, with subsequent intensification and transformation of this technology coinciding with the global emergence of agriculture in the early Holocene. On the island of New Guinea, agriculture first emerges in the highland Wahgi Valley, potentially from c. 9 kya, and clearly evident by 6.5 kya. Approximately 400 km further east in the highland Ivane Valley, long-term occupation sequences span the Holocene and late Pleistocene, but there is currently no direct evidence for wetland agriculture. Here, we report rare evidence for ground stone implements from a secure mid-Holocene archaeological context in the Ivane Valley. The Joe’s Garden site has flaked and ground stone artefacts with significant starch assemblages dating to approximately 4.4 kya. We present the first empirical evidence for the function of stone bowls from a New Guinea highland setting. Usewear and residues indicate the grinding and pounding of endemic starch-rich plant foods. Geometric morphometric analysis of starch grains shows that at least two taxa were processed: Castanopsis acuminatissima (nut) and Pueraria lobata (tuber). This regional example adds to our understanding of the trajectories of diverse plant food exploitation and ground stone technology development witnessed globally in the Holocene.

Ancient starch and usewear analyses of an excavated pestle fragment from the Upper Kaironk Valley, Madang Province, Papua New Guinea

“…Usewear residue studies have previously been undertaken on one excavated mortar fragment from the Joe's Garden site in the Ivane Valley (Central Province), and on two excavated pestle fragments from the Waim site in the Schrader Range (Madang Province) (Field et al 2020;Shaw et al 2020). The starch grains identified on all three artefacts were attributed to Castanopsis acuminatissima, a forest tree species that is ubiquitous across the highlands, occurring between 570-2440 m asl (above sea level) and documented in the vegetation histories of the region (e.g.…”

“…While it has been documented from mid-Holocene contexts, it is likely to have been exploited over a longer period (Bourke 1996;Field et al 2020;Shaw et al 2020).…”

“…Local communities have no knowledge about their manufacture or intended use. Despite much speculation among researchers for over 100 years, the primary function of these implements is only now becoming clearer (Barton 1908;Bulmer 1964;Field et al 2020;Seligman and Joyce 1907;Shaw et al 2020;Swadling and Hide 2005;Watson 1968). The recent discoveries of mortar and pestle fragments from securely excavated and dated contexts in widely separated geographic locations, and the significant advances in ancient starch studies over the past two decades, and in combination with usewear analyses, have yielded much-needed new information on the associated uses of these tools (e.g.…”

“…The recent discoveries of mortar and pestle fragments from securely excavated and dated contexts in widely separated geographic locations, and the significant advances in ancient starch studies over the past two decades, and in combination with usewear analyses, have yielded much-needed new information on the associated uses of these tools (e.g. Field 2015, 2018;Field et al 2016Field et al , 2020Hayes et al 2021). As mortars, pestles and carved objects are found across New Guinea and the Bismarck Archipelago (see Swadling 2021:Fig.…”

Decodificando la memoria artefactual desde el sur de Sudamérica. Fortalezas del análisis integral de artefactos líticos

“…Los trabajos señalados abordan artefactos líticos tallados, de molienda, manufacturados por picado y abrasión, y modificados por uso, o conjuntos completos de artefactos en múltiples sitios de diversa cronología de Australia y Papúa Nueva-Guinea que son analizados mediante la conjunción de diferentes líneas de evidencia (Fullagar 1986;Fullagar y Jones 2004;Field et al 2020;. Más recientemente, han surgido colaboraciones con investigadores en diferentes partes del mundo, como Indonesia, Rusia o China, donde se aplican las estrategias de trabajo y vías analíticas desarrolladas (Bordes et al 2018;Bordes et al 2020;Fullagar et al 2021).…”