When did we start drinking the milk of other animals? And how did the practice spread? A new study led by scientists from Germany and Kenya highlights the critical role of Africa in the story of dairying, showing that communities there were drinking milk by at least 6,000 years ago. By extracting tiny bits of preserved proteins from the dental calculus, researchers can detect proteins specific to milk, and even specific to the milk of particular species. So, the oldest records show that 6,000 years ago people in Africa drank goat milk. Early herders also processed milk into dairy products like yogurt that were easier to digest.