Prehistoric farmers were keeping cows for their milk seven millenia ago in what is now the Sahara desert, researchers say

British scientists have found microscopic stains of dairy products on cooking pots from Libya dating back to the fifth millennium BC.

Chemical analysis of the pottery artefacts suggests Africans were dairy farming during a time when the region was humid and 'green'.

The findings published in Nature reveal milk was an important part of their diet, in spite of lactose intolerance which made it difficult for early man to digest the sugar in dairy food.

In northern Africa the domestication of cattle, sheep and goats emerged long before plants were used as crops.

The importance of cattle in the lives of ancient humans in this region thousands of years ago is reflected in the extensive rock paintings, which contain numerous scenes depicting cattle and even milking.

But reliable dates for this art are hard to ascertain, and little direct evidence exists to discern whether dairying was widely practised.

Professor Richard Evershed, of the University of Bristol, and colleagues have previously identified a technique based on the carbon compositions of milk fatty acids to accurately date early dairying practices in Europe and Asia.

Using the same method, they uncovered evidence for the processing of dairy products in the pots from the Libyan desert.

Prof Evershed said: 'The finding of dairy fat residues in pottery is consistent with the processing of dairy products, suggesting how these people could have consumed milk products in spite of lactose intolerance.'

The pots were very porous and during cooking dairy fats floated to the surface of the water and were absorbed into the clay.

Source