Identifying archaeological parenchyma in three dimensions: Diagnostic assessment of five important food plant species in the Indo-Pacific region

Abstract

Archaeobotanical evidence for the exploitation of vegetatively propagated underground storage organs (USOs) in the tropical regions of Australia, Southeast Asia and the Pacific is currently limited. Although there have been several key studies of archaeological parenchyma published in the past two decades, systematic application of identification methods for vegetatively propagated crop species utilising charred, desiccated or waterlogged remains of parenchymatous tissue is not undertaken on a regular basis. Here, microCT imaging technology is used to compile a three-dimensional virtual reference collection of parenchymatous tissues for five key USO species known to have been extensively cultivated by people in these regions. The five species are Dioscorea alata, Dioscorea esculenta, Colocasia esculenta, Alocasia macrorrhiza and Ipomoea batatas. These reference samples are used to illustrate the character of the virtual, microCT derived reference collection, and they also capture inter-species differentiation and intra-species morphological variation characteristic of many tuberous root crops.