Evershed and Dunne’s team analysed pottery shards dating from 5200 to 3000 BC, exavated from the Takarkori rock shelter in southwestern Libya’s Acacus mountains. Although today this area is in the Sahara, 7,000 years ago it would have been more lush landscape capable of supporting dairy animals. The Takarkori shelter and others nearby are home to vivid and colourful rock art depicting cattle, some with full udders, and even pictures of people milking cows, but these images are nearly impossible to date precisely. Archaeologists have also found fragments of domestic cattle bones at these sites, but these do not indicate whether the animals were kept for meat, dairying or other uses. Evershed and Dunne hoped to overcome these problems by examining fat residues left on the pottery shards.