Ms Macken studied two fossil sites – Wet Cave and Blanche Cave – located within South Australia’s Naracoorte Caves World Heritage Area to determine the age of the deposits, thereby providing greater clarity on climatic changes and mammal communities in the region.
While the traditional method for dating archaeological and paleontological materials, known as radiocarbon dating, provided estimated age ranges for the two sites overall, Ms Macken said there were numerous information gaps on the age of the individual sedimentary layers.
“The caves are within 400 metres of each other and there was some pre-existing evidence that showed they were of similar age but the multiple layers within the sites were not well documented,” Ms Macken, based in the School of Biological Sciences, said.
“I took all the information that was available on both the age of the sites and the characteristics of the sedimentary layers and used a new statistical modelling technique – one that has never been applied to an Australian fossil site before – to make predictions on how old parts of the deposits were that we didn’t have dates for,” she said.
“For example, the modelling showed one layer in Wet Cave was 18,000 to 16,000 years old so I did the same test in Blanche Cave to see if any of its layers were the same age.”
Ms Macken said the overarching aim of her research was to understand if and how the community of small mammals living within the region of the caves changed through the last glacial cycle (50,000 to 10,000 years ago).