Archaeologists studying the residue on a stone flake found in the Sibudu Cave have learned that prehistoric dwellers in the South African site made use of a powdered paint mixture of milk and ochre to decorate stones and woods or even adorn themselves 49,000 years ago.

While ochre paint powder production has been widely documented as early as 125,000 years ago in ancient African villages and European archaeological sites, this is the first time milk proteins have been identified as its binder.

Most likely, the milk was obtained from the lactating wild bovid family of animals:  buffalo, eland, kudu and impala. "Obtaining milk from a lactating wild bovid also suggests that the people may have attributed a special significance and value to that product," said Paola Villa from the University of Colorado, who was one of the authors of the paper, according to a press release.

The experts note that domestication of cattle in South Africa didn't begin until 2,000 years ago, however, "Wild South African bovids are known to separate from the herd when giving birth and usually attempt to hide their young, a behavior that may have made them easy prey for experienced Middle Stone Age hunters," the researchers further stated in their paper.

The paint has been well-preserved in the stone flake discovered in the Sibudu rock shelter in KwaZulu-Natal. The site had been earlier identified as the dwelling place of Homo sapiens in the Middle Stone Age between 77,000 to 38,000 years ago, according to Science Daily.

Scientists employed different types of analyses to check for the presence of casein on the stone flake. Casein is protein found in milk. Because the indigenous people of South Africa practice body painting, the experts said that they have likely used milk-based paints so that their adornment and decorations lasts.

"Body painting is widely practiced by the indigenous San people in South Africa, and is depicted in ancient rock art. While there are no ethnographic precedents for mixing ochre with milk as a body paint, the modern Himba people in Namibia mix ochre with butter as a coloring agent for skin, hair and leather clothing," Villa wrote in the paper.

The findings was published in the journal PLoS ONE.