ALONE IN MY parents’ kitchen on a recent visit, I was drawn to the sheets of slides scattered on the table.

I’ve walked past my father’s organised chaos most of my life. Dad was always surrounded by images from his work in the field, as a scientist specialising in climate change. This time it was different. I stopped and lifted one up. I felt I was sneaking a look at a forbidden world. Expecting to see boring sand and soil or aerial shots of geological sites, I was instead confronted with the most amazing series of slides he had ever taken. A window to Australia’s ancient past opened – at least 40,000 years stretched between us. I was entranced. These traces of ancient Aboriginal Australia had echoed across the country, causing a revelation over thirty years ago. They had been in my father’s collection all this time, yet I’d never seen them.