More than 7,000 years ago, prehistoric people in the African Sahara were making dairy products, such as butter, yogurt and cheese.
The discovery, based on the identification of dairy fats on ancient pottery shards found in Libya, is the first to provide a definitive date for early dairy farming in Africa. Adding to findings from Europe and the Middle East, the study points to milk products as a main reason why people in many places may have chosen to give up the hunter-gatherer lifestyle in favor of a more settled existence.
“What we’re really beginning to know is that cattle were incredibly significant to early peoples,” said Julie Dunne, an archaeological scientist at the University of Bristol in the United Kingdom. “They gave a remarkably calorific source of food and allowed populations to expand dramatically. Milk and dairying seem to be so significant in human development, remarkably so.”
Plenty of research has documented the domestication of sheep, goats and cattle, as well as the use of dairy products, beginning around 9,000 years ago in parts of modern-day Turkey, 8,000 years ago in eastern Europe and 6,000 years ago in Britain.
In Africa, details have been murkier. Fossil evidence suggests the arrival of domesticated milk-producers in North Africa by about 8,000 years ago with an increase in animal numbers over the next 1,000 years, but remains are spotty. And even though archaeologists have discovered vivid rock art depicting cattle and even milking scenes in Algeria and other parts of the Sahara, it is impossible to accurately date those paintings.
For the new study, Dunne and colleagues analyzed organic residues on 81 well-dated pieces of pottery taken from the Takarkori rock shelter in the Libyan Sahara. The samples turned out to be incredibly well preserved, containing fat residues at high concentrations, probably because of the region’s dry conditions -- though the climate there was much wetter during the period considered in the new study.
Evidence showed that some pots were used to hold plant oils. But many contained chemical signatures that were unambiguously from animal fats, the researchers report today in the journal Nature. Analyses revealed the remains of dairy products made from cow, goat and sheep’s milk, dating back to between 7,200 and 5,800 years ago.
At that time, Africans had not yet developed the genetic mutations that allow people to digest milk, according to other research. So, the Sahara’s lactose-intolerant dairy farmers were likely making yogurt and cheese rather than drinking straight from the udders of their animals. Only after people learned to process dairy foods did their bodies develop the ability to drink pure milk -- through mutations that appear to have happened independently as many as three or four times in Africa.
It is now becoming clear that dairying was a transformative development in human history, said Joachim Burger, an evolutionary anthropologist at the University of Mainz in Germany. Given their carbohydrate and nutrient profiles, dairy products would have been far superior to what people could get from hunting and gathering alone. And when our ancestors figured that out, society changed forever.
“The general question behind all this is what actually made man to become sedentary and change his lifestyle completely,” Burger said. “Milk is not just a side effect of this change. It may even be a driving force behind it.”