Microfossil analysis of sediments from Carpenters Gap 1 and 3 archaeological sites, Kimberley, Western Australia, provides evidence for processing cf. Dioscorea transversa and cf. Colocasia esculenta since c. 30,000-25,000 cal BP

Abstract

Previous palaeo-starch studies in Australia, almost all using stone tool analysis, have yielded a considerable body of information on Indigenous plant processing. Here we build on this work with starch analysis of 58 sedimentary samples from Carpenters Gap 1 and 3 rockshelters, Kimberley, Western Australia.

Starch of two species native to the region, supported by calcium oxalate crystal and xylem evidence, was identified at both sites: cf. Dioscorea transversa (pencil yam) tuber, dated from 30,372-27,846 cal BP; and cf. Colocasia esculenta (taro) corm, dated from 26,202-25,143 cal BP. The taro material has not previously been reported in Australian archaeological contexts. We discuss other possible sources of this starch type that have similar, relatively tiny sized grains, showing several differentiating features of taro starch.

Results show promise for isolating starch and associated material from archaeological sedimentary records in Australia, which can provide a complimentary line of evidence alongside stone tools. The presence of another microfossil type, euglenoid cysts, provides evidence for gathering wetland/aquatic resources.

Keywords

Rockshelter, starch, Dioscorea transversa, Colocasia esculenta, euglenoid cysts.