Chemical analysis of pottery shows the first evidence humans in prehistoric Saharan Africa used cattle for milk nearly 7,000 years ago, British researchers say. Scientists from the University of Bristol said an analysis of fatty acids extracted from unglazed pottery excavated from an archaeological site in Libya showed dairy fats were processed in the vessels. Around 10,000 years ago the Sahara was a wetter, greener place that today and early hunter-gatherer people lived a semi-sedentary life, using pottery, hunting wild game and collecting wild cereals, the researchers said. Then, around 7,000-5,000 years ago as the region became more arid, the people adopted a more nomadic, pastoral way of life and cattle became more important, they said. While engraved and painted rock art found widely across the region includes many vivid representations of cattle, there had been no direct proof these cattle were milked -- until now. \"We already know how important dairy products such as milk, cheese, yogurt and butter, which can be repeatedly extracted from an animal throughout its lifetime, were to the people of Neolithic Europe, so it\'s exciting to find proof that they were also significant in the lives of the prehistoric people of Africa,\" researcher Julie Dunne said in a Bristol release Wednesday. The findings also provide a background for understanding the evolution of the gene for lactose intolerance that appears to have arisen once prehistoric people started consuming milk products, she said.