PEOPLING

Crossing to Australia

~65,000 years ago (disputed)

Palaeolithic · Middle Stone Age · Last glacial

At Madjedbebe rock shelter, in northern Australia, people were grinding ochre and hafting ground-edge axes by about 65,000 years ago, the age optical dating gives to the sands that held their tools. Reaching Australia meant crossing open sea beyond sight of land, whatever the route through the islands: the first ocean voyage in the human story that chance can hardly explain.

Why it matters

No land bridge ever ran to Sahul. Somebody built craft, loaded families and steered into water with no far shore in sight; enough of them landed to found a continent's population. The date is fought over because much hangs on it: if people were in Australia by 65,000 years ago, the expansion out of Africa was earlier or faster than the genetic consensus allows, and the first Australians may have shared the land with megafauna far longer than assumed.

Dating & uncertaintyDisputed

Optical dating at Madjedbebe gives 65,000 +/- 6,000 years for the oldest occupation. Critics argue that termites and other disturbance carried artefacts down into older sand, and that no other Australian site yet confirms such antiquity; the excavators reply that refitted artefacts and intact hearths rule out major mixing. A conservative floor of about 50,000 years is safe; 65,000 remains the excavators' published estimate.

Sources

1. Clarkson et al. (2017), Nature · Human occupation of northern Australia by 65,000 years agodoi:10.1038/nature22968
2. Williams et al. (2020), Geoarchaeology · Identifying disturbance in archaeological sites in tropical northern Australia: implications for previously proposed 65,000-year continental occupation datedoi:10.1002/gea.21822
3. Clarkson et al. (2018), Australian Archaeology · Reply to comments on Clarkson et al. (2017) 'Human occupation of northern Australia by 65,000 years ago'doi:10.1080/03122417.2018.1462884

Our species’ history as one day

19:02:514 h 57 min before midnight

if the 315,000 years of Homo sapiens were compressed into a single day