Methods of dating archaeological sites
At this site, one of the most significant archaeological sites in Australia, a female cremation burial was identified in 1969 and provided evidence of the world's oldest known cremation rite - around 26 000 years old.
A few hundred metres away, and some thousands of years older, a man was buried (called Mungo 3).
Contemporary Aboriginal artists use a considerable variety of materials and techniques in painting.
Some of these materials are rooted strongly in tradition - such as the use of ochres in the Kimberley and, to a lesser extent, ochres on bark from Arnhem Land.
In 1999 the remains were examined again and dated using more recent techniques.
Alan Thorne and his colleagues obtained an estimate for the age of the skeleton of 62,000 6000 years. The results have been disputed by a number of archaeologists, and many believe that the limit of modern human occupation of Australia is around 45 000 years.
Paints are made by grinding the source rock to a powder and then mixing it with a fluid to bind it together.
Traditionally this fluid could be saliva or blood, while in contemporary art an acrylic binder is more commonly used.
Most have been carbon dated with ages between 10 000 and 40 000 years (the effective limit of carbon dating), and one site had what appears to be an artists palette of ochres - dated 18 000 years old.
His father then sprayed his hand with red ochre against the rock - leaving a stencil he could still recognise many years later.
The main function of the stencils was to record people's presence and association with a site or to identify a particular painting.
Ochres from western Arnhem Land Ochres give a rich warm colour to contemporary artworks from the Western Desert, Kimberley and Arnhem Land.
The surfaces it was used on varied widely from rock, wood and bark to the skin of participants in ceremonies.