Historians are being forced to re-think the date when Australia's Aboriginal people first had contact with the outside world, thanks to some new rock art analysis. Archaeologists have carbon-dated a painting of an ancient boat, and now believe southeast Asian sailors were visiting Australia as early as the mid-17th Century.
This painting at a rock shelter in remote Arnhem Land in the Northern Territory could change the timeline of Australian history.
"First contact" is the name given to the moment when outside cultures first came across Australia's indigenous people, and this painting is thought to be the earliest representation of that point in time.
The boat shown is believed to be a perahu vessel which was popular in south-east Asia. The painting is being interpreted as an indication of when Aboriginal people first encountered outsiders.
The beeswax dots on the rock face have now been carbon-dated, giving a surprisingly early date of between 1624 and 1674, according to archaeologist Paul Tacon.
That's around a century earlier than when historians thought contact first took place.
Some archaeologists say the finding is an important historical development, but another archaeologist is not convinced.
In an effort to discover more about the period, researchers have also been excavating along the coast where Macassar fishermen from southeast Asia used to fish for trepang.
And some of the rock art is throwing up new mysteries.
Archaeologists believe the presence of a monkey in one of the paintings shows that Aboriginal people could even have been travelling to Asia, as monkeys are not found in Australia.