Determining the timing and pattern of human colonisation in Australia: Proposals for radiocarbon dating 'early' sequences

At present, radiocarbon dating estimates of the age of human occupation of archaeological sites in Australia are virtually all based on single, or comparatively few, radiocarbon dates at the depth associated with the earliest cultural remains. Several new radiocarbon 'calibration' curves for the early occupation period of Australia (>30,000 ¹⁴C BP), some of which suggest significantly rapid and extreme shifts in apparent radiocarbon age, have become available in recent years. While there are currently major discrepancies between these curves, improvement and regular revision of the 'accepted' calibration curve is a recognised priority within the international radiocarbon community. Thus, the opportunity for more precise interrogation and confident interpretation of the conventional radiocarbon timescale is likely to emerge in the future. In the meantime, we suggest more intensive dating of the critical initial occupation levels of stratigraphic sequences to allow maximum exploitation of any future radiocarbon calibration curve structure (eg. using 'wiggle-matchine' and/or Bayesian statistics). Such an approach should assist in the future development of a more robust model of the patterning of human colonisation of Australia.