A collection of tiny perforated shell beads dates back 75,000 years and appears to be the oldest human ornament ever found.

Archaeologists claim to have discovered the world's oldest beads, dating back around 75,000 years.

Clusters of around 17 shells from a tiny mollusc, Nassarius, were unearthed in a layer of sediment dating from the Middle Stone Age.

The perforated shells found in the Blombos Cave on the edge of the Indian Ocean in South Africa appear to have been strung together as beads.

Around 30,000 years older than any other personal ornament ever found, the shells appear to have been selected and deliberately modified by ancient Africans over 75,000 years ago, marking the adoption of symbolically mediated behaviour.

Christopher Henshilwood, program director of the Blombos Cave Project, said: "The Blombos Cave beads present absolute evidence for perhaps the earliest storage of information outside the human brain."

The Blombos Cave project has turned up a number of interesting discoveries, including series of tools that have called into question assumptions about the evolution of critical behaviour in humans.