Archaeological insights have traditionally been restricted by the preservation of organic material and the presence of diagnostic morphological features. However, in the case of non-woody plants few visible remains are preserved while faunal identification is often skewed towards easy-to-identify taxa. This gap in the ecological record ultimately leads to an imbalance in the analysis of plant and animal material. This issue is particularly acute in Australia where, for instance, non-woody plants had many important and varied uses in Aboriginal societies.
Southwest Western Australia is a biodiversity “hotspot,” rich in archaeologically and culturally significant Aboriginal sites (e.g. Devil’s Lair). An absence of long pollen records in this region has limited archaeological and palaeo-environmental inferences. Additionally, typical of Australian archaeological sites, more than 80% of the bone fragments previously recovered from past excavations at a number of sites in the area had no diagnostic features at all. With these issues in mind, four archaeological deposits were revisited with the goal of applying ancient sedimentary DNA (sedaDNA) analysis and a novel bulk-bone metabarcoding (BBM) technique across stratigraphical layers to analyse ecological shifts against the backdrop of episodic human occupation and changing climate.
The approach adopted in this project to studying past and present ecological shifts is a useful adjunct to traditional ecosystem monitoring regimes. This poster highlights key considerations when embarking on HTS projects, offers suggestions for experimental design and applies the methodologies proposed in one of only a handful of difficult to characterise biodiversity hotspots worldwide. The data generated to date suggests that the use of sedaDNA and BBM techniques will add significantly to our understanding of other archaeological sites across Australia and worldwide.