Exploitation, technology and function of plant resins in Oceania: molecular analysis of ethnographic museum artefacts and the implications for archaeological resin analysis

Thesis

Oceania has an extremely diverse and unique flora that includes many endemic species of restricted geographic range. This flora comprises coniferous, deciduous, and monocot plants and trees that include many resin-producing species. Plant resins have a long ethnobotanical history in Indigenous Oceania, as is recognised by some rare archaeological finds as well as a rich ethnographic record. In this study, gas chromatography-mass spectrometry (GC-MS) has been employed to chemically investigate resins of ethnobotanical importance in Oceania including Australia. A total of 173 samples of resinous material from ethnographic artefacts, currently held in museums, was analysed alongside botanically identified reference materials from in and around the area. The aim was to both contribute to our understanding of the role of resins in Indigenous Oceania, and provide a framework for efficiently and effectively analysing valuable resinous archaeological finds from the region.

Four main types of resin were found to be regularly used in various regions of Oceania, namely conifer-type diterpenoid, non-conifer-type diterpenoid, triterpenoid and phenolic resins. A number of samples have been identified to source family, genus and in some cases species, by comparison with authenticated resin samples collected from botanic gardens and herbariums. The results show that a much wider range of plant resins have been exploited in Oceania than has been generally recognised, particularly in reference to the descriptions of resin use in the ethnographic literature. The chemical characterisation of a range of resins including samples from three species that were previously unpublished has been presented. Also presented are the chromatographic profiles of ethnographically collected putative spinifex (Triodia) and northern ironwood (Erythrophleum chlorostachys) resins. The range of functions served by plant resins in Indigenous Oceania is discussed with an emphasis on both hafting and non-hafting uses.

Authors: Bradshaw, FG

• DOI: 10.5287/ora-eo7prpkv8
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: Ethnobotany; Canarium resin; Hafting; Agathis resin; Australia; Triterpenoid; Spinifex resin; Oceania; Diterpenoid; Resin analysis; Archaeology; Xanthorrhoea resin; Gas chromatography - mass spectrometry
• Subjects: Ethnological museums and collections; Archaeological chemistry