We are descended from bark chewers, 2 million-year-old fossil reveals (+video)
By analyzing teeth and carbon remains from isotopes from fossil specimen Australopithecus sediba, German scientists discovered early humanity chewed bark.
The immediate ancestor of the human lineage may have lived off a woodland diet of leaves, fruits and bark instead of a menu based on the open savanna as other extinct relatives of humanity did, researchers say.
Food was a major environmental force that shaped the human lineage – perhaps influencing key moments such as when humans' ancestors started walking upright – and these new findings help reveal the complex evolutionary paths these ancestors took in response to the world around them, the scientists add.
The findings are based on fossils of the extinct hominin Australopithecus sediba that were accidentally discovered in 2008 by the 9-year-old son of a scientist in the remains of a cave in South Africa. The fossils were 2 million years old.
A hominin is the lineage that includes humans and their relatives after they split from those of chimpanzees. Australopithecus means "southern ape" and is a group that includes the iconic fossil Lucy, while sediba means "wellspring" in the South African language Sotho. This hominin's mix of human and primitive traits has made a strong case for it being the immediate ancestor of the human lineage. [Image Gallery: Our Closest Human Ancestor]