Sean Ulm

is when you reveal what the population in Australia of Indigenous people used to be.

Millions?

And Corey Bradshaw, of course, at Flinders University.

That's right.

In there, South Street.

And one of the aspects of having a much larger population, in some ways, the picture we've got, often wrongly, of these isolated groups being on the map in complete isolation, but maybe, you know, the odd wandering and sharing a bit of language.

But when you've got three million, obviously you can have the to-ing and the fro-ing.

And I often think of the Greek islands and the way in which innovation happened, suiting the land and the landscape and the sea.

And that would be fostered by that sort of interaction.

And in Lizard Island, northern Queensland, that's shown more and more by Sean and the pottery being discovered.

Because it was pottery made somewhere else and pottery made on the island.

So obviously to-ing and fro-ing was going on.

The picture of...

That Australia, so different.

Sixty or more thousand years, 65,000 years.

This is a gigantic period.

And from what you've been saying, obviously, terra nullius, which was very, very iffy from the beginning, a bit of a legalistic device, now it looks preposterous when you look at the history.

The land was occupied and used and involved in ways which are just stunning and varied.

This is The Science Show on ABC Radio National, a special around the first inventors and the human, as well as the biological history of Australia.

Back to Billy Griffiths.