World's oldest ground-edge implement discovered in northern Australia

Evidence for stone tool-use among our earliest hominid ancestors dates to 3.4 million years ago. However, the first use of grinding to sharpen stone tool edges such as axes is clearly associated with modern humans, otherwise known as Homo sapiens sapiens.

Monash University archaeologist and member of the team who made the discovery, Dr Bruno David, said while there have been reports of much older axes being found in New Guinea, the implements were not ground.

"This suggests that axe technology evolved into the later use of grinding for the sharper, more symmetrical and maintainable edges this generates," said Dr David.

"The ground-axe fragment is dated to 35,000 years ago, which pre-dates the oldest examples of ground-edge implements dated to 22,000-30,000 years ago from Japan and Northern Australia."

Archaeological excavations undertaken in May 2010 at Nawarla Gabarnmang in Northern Australia uncovered the artifact.

Nawarla Gabarnmang is a large rock-shelter in Jawoyn Aboriginal country in southwestern Arnhem Land. The discovery of the rock-shelter was made by Ray Whear and Chris Morgan from the Jawoyn Association while flying by helicopter on 15 June 2006.

The discovery of the axe was made by a team of researchers including Jean-Michel Geneste from the Centre National de Prehistoire of the Ministry of Culture in France, Hugues Plisson from the Centre National de la Recherche Scientifique at the University of Bordeaux in France, Christopher Clarkson from the University of Queensland, Jean-Jacques Delannoy from the Centre National de la Recherche Scientifique at the University de Savoie in France and Fiona Petchey from the University of Waikato in New Zealand.

"Axes fulfilled a unique position within the Aboriginal toolkit as long use-life chopping tools, were labour intensive to manufacture and highly valued," said Dr David.

"During the late 19th and early 20th centuries, axes were understood by local Aboriginal communities to carry with them the ancestral forces which characterised the particular quarry from which they came,"

"Their trade across the landscape moved not just the tool itself, but more importantly the symbolic and ancestral forces of their point of origin. The Nawarla Gabarnmang axe, found some 40km from its source, is evidence of 35,000 years of the movement of tools, technologies and ideas across the northern Australian landscape,"

"This new evidence for the earliest securely dated ground-edge implement in the world indicates that Australia was an important locale of technological innovation 35,000 years ago."

"This discovery will assist researchers in Australia and around the world as we examine the evolution of human behaviour and the earliest technological advancements," said Dr David.

The find is reported in the December issue of Australian Archaeology, the official journal of the Australian Archaeological Association Inc. The project was funded by the Australian Government's Indigenous Heritage Program administered by the Department of Sustainability, Environment, Water, Population and Communities.