Bone tools found in a remote north Australian cave have been dated as being more than 35,000 years old, making them some of the oldest in the nation.
Eight tools made from kangaroo bone have been excavated from Riwi Cave in the southern Kimberley, by archaeologists in the early 1990s with support from the nearby Mimbi community.
It's only now that better dating techniques could put the tools at between 35,000 and 46,000 years old.
Carved from Kangaroo ulna, tibia or fibula, the pointed bone tools were used to process spinifex resin, basket weaving, working plant fibres or to hunt birds and fish.
It's rare the tools survived northern Australia's harsh climate for almost 46 thousand years and shows the range of skills first Australians were using.
"Bone technology in Australia tends not to survive the long periods of time that people have been here," Michelle Langley from Griffith University said.
"We knew bone tools were being used but we simply weren't finding them.
"They were decomposing before we could pick them up again.
Riwi is a limestone cave on Gooniyandi country 90 kilometres east of Fitzroy Crossing and has previously yielded shell beads, a boomerang, seeds and charcoal from cooking fires.
Window into early technology
Archaeology Professor Jane Balme from University of Western Australia has spent many hours in Riwi cave and worked with experts across the nation to identify the tools.
Professor Balme said the tools showed the importance of organic materials in the early technologies of First Nations people.
"They provide a window into a greater diversity of activities undertaken by people than are revealed by stone artefacts alone," Professor Balme said.
Dr Langley said the tools would have taken time and skill to make.
"Using the natural anatomy of the bone, they've been pointed at one or both ends depending on what they're used for. They've been flaked or ground into shape."
Dr Langley said her work allows her to make connections to the past.
"It's always exciting, especially when you get something unexpected," she said.
The research, which also involved Australian National University, has been published in the International Journal of Osteoarchaeology.
