Billy Griffiths

Indigenous people all over the continent invented extraordinary numbers of things.

And I think we get this palimpsest in archaeology, just this residue of what that extraordinary technological diversity was like.

And this reminds me of the senior lips effect.

Have you heard of this?

No.

So the senior lips effect, and I need to thank my paleontological colleagues for this, is a principle that the fossil record will not preserve the youngest or the oldest example.

And I often think about this in archaeology and Majabibi is a good example of this.

If Majabibi is 65,000 years or older and it's 350 kilometres inland, it's clearly not the footprint

of the first person to step foot on the continent, that the senior lips effect principle would tell us that the first footprint is sometime earlier than that.

So based on that principle, we've done modelling that shows that the first entry to the continent must have been 73 to 75,000 years ago.

And I think those other forms of evidence we're talking about line up with that.

The other part of that is about the cultural diversity we witness.

When Europeans invaded Australia, there were at least 250 separate nations speaking different languages, up to 600 dialects.

Each of those nations had its own history, culture.

But when we go back in time, that 73,000, 75,000 years, I often think about this with the continental shelves where the Gulf of Carpentaria was dry land for most of the Indigenous history of the continent.

There was 500 kilometres of dry land off the northwest Kimberley coast.

There were generations of First Nations people who were born, lived and died on land which is now deep underwater.

those societies would have had their own technological traditions.

So we've got that vector of cultural, technological, social diversity, not only spatially, but temporally as well.

So we've got those traditions of invention cycling over time.