LUMINESCENCE DATING OF ROCK ART AND PAST ENVIRONMENTS USING MUD-WASP NESTS IN NORTHERN AUSTRALIA

Mud-nesting wasps are found in all of the main biogeographical regions of the world(1-3), and construct nests that become petrified after ab andonment, Nests built by mud-dauber and potter wasps in rock shelters in northern Australia(1,4) often overlie, and occasionally underlie, prehistoric rock paintings. Mud nests contain pollen, spores and phyto liths from which information about local palaeovegetation can be glean ed, Here we report a new application of optical dating(5-7), using opt ically stimulated luminescence (OSL), and accelerator mass spectrometr y (AMS) C-14 dating of pollen(8) to determine the ages of mud-wasp nes ts associated with rack paintings in the Kimberley region of Western A ustralia(9,10). Optical dating of quartz sand (including the analysis of individual grains) embedded in the mud of fossilized nests shows th at some anthropomorphic paintings are more than 17,000 years old. Reco nstructions of past local environments are also possible from the rang e of pollen and phytolith types identified. This approach should have widespread application to studies of rock-art dating and late Quaterna ry environmental change on continents where mud-wasps once Lived and o ther sources of palaeoecological information are absent.