Dunne and her colleagues analyzed tiny fragments of pottery taken from the Takarkori rock shelter, a prehistoric dwelling in the Libyan Sahara. They ground up small pieces of the pottery, conducting chemical analyses to investigate the proteins and fats embedded in the shards. By doing so, the researchers could see what the pots once held.
They found evidence of a varied diet, with signs found for plant oils and animal fat. The most common fats were of animal origin, Dunne said, with some deriving from flesh and others from milk. The most dairy-fat rich pottery shards came from the same time periods when more cattle bones are found in the cave layers, the researchers reported today (June 20) in the journal Nature.
By looking at variations in the carbon molecules in these preserved fats, the researchers were able to get an idea of what kind of plants the cattle were eating. They found their diets varied between so-called C3, or woody plants, and C4 plants, which include grasses grains and dry-weather plants. (C3 and C4 refer to the type of photosynthesis these plants use.)
That fits with the archaeological understanding of this early herding civilization as moving between seasonal camps, Dunne said. [Album: Faces of a Threatened Tribe]