Scientists say they've discovered the oldest known rock art in Australia.
It's a painting of a kangaroo created more than 17,000 years ago.
Researchers used mud wasp nests around the art to estimate the ages.
They theorized that if the nests were built on top of the rock, the art is older, and if they were built below the art the nests are older.
They found the majority of the paintings were made between 17,000 and 13,000 years ago.
