AUSTRALIA: Some very old rock art, such as the Gwion-style paintings that are found in the Kimberley region of Western Australia, is notoriously difficult to date because the pigments no longer contain organic material. However, experts were able surmount this challenge by instead dating organic material from millennia-old mud wasps’ nests on rock facades that had been painted over by Aboriginal artists long ago. The researchers estimate that most of the paintings’ enigmatic anthropomorphic figures were created 12,000 years ago.