Ancient beads dating to about 82,000 years ago have been uncovered in a limestone cave in Morocco.
The beads were used for decorative purposes and are one of the earliest signs of the beginnings of modern human behaviour or culture.
The twelve beads were uncovered in Taforalt in Eastern Morocco by an international team of archaeologists. The shell beads are coloured with red ochre, have holes in their centres, and show signs of being hung.
The project was led by Oxford University's Institute of Archaeology and Morocco's National Institute for Archaeological Sciences. The team carried out four independent dating methods on the beads resulting in a date of 82,000 years.
'For me these new finds settle the question whether there was widespread symbolic behaviour by early modern humans by 75,000 years ago ,' says Chris Stringer, human origins expert at the Natural History Museum, and a co-author of the paper.
These beads are not the oldest found in the world. That title belongs to two beads in the Natural History Museum collections uncovered from Skhul in Israel in the 1930s. Last year they were dated to around 100,000 years old.
'Some workers questioned the Israeli evidence because there were only a couple of shell beads and they were from old excavations,' Chris adds. 'Whereas, there are many more of the new finds, they have been found during recent excavations , and the sediments containing them have been directly dated.'
These beads, and similar ones from Israel and South Africa, come from the same genus or group of species. The similarities provide evidence that human ideas could cross wide areas of Africa in ancient times.
'If you draw a triangle covering the three furthest known locations of Homo sapiens between 75,000-120,000 years ago, that triangle stretches from South Africa to Morocco to Israel,' says Chris.
'Shell beads are now known at all three points of that triangle, with three different stone tool industries. So such behaviour had probably spread right across the early human range by this time, and would have been carried by modern humans as they dispersed from Africa in the last 100,000 years.'
Fossil and genetic evidence suggests modern humans, or Homo sapiens, originated in Africa about 200,000 years ago . They migrated beyond Africa and the Middle East about 50-70,000 years ago and eventually spread throughout the world.
Evidence of more complex human behaviours such as art, symbolism and complex burials tells us a lot about the evolution of culture in our human relatives. This new find adds to the evidence for modern human behaviour beginning in Africa long before it reached Europe .
The research is published by Proceedings of the National Academy of Sciences