Libya: Ten thousand years ago, the Sahara was a far greener place. As it became more arid, people came to rely heavily on livestock, and rock art from the region depicts cattle and even milking. But rock art is hard to date, making it difficult to identify the onset of dairy practices in Africa. New analysis of residues in pots has revealed evidence of milk fat that can be reliably dated to around 7,000 years ago. This early onset of dairy use might help unravel the evolution of the gene that lets many people digest lactose.