Two tiny pieces of engraved ochre are the oldest works of art ever discovered, scientists say, showing the artist in mankind was awakened, in Africa at least 77,000 years ago.
Found in Blombos Cave in South Africa, the pieces are carved with a pattern of crossed lines, showing that humans had a capacity for abstract thought, and use of symbols, tens of thousands of years before they spread from Africa to Europe.
They also show that, some 4,000 generations ago, the African ancestors of all present-day humans had acquired grammatical speech.
"This is an abstract pattern, a symbol which stands for something we don't understand," said Christopher Henshilwood, of Cape Town University, who leads a project to investigate Blombos Cave.
The ochre artefacts, a few centimetres long, were found in 1999 and 2000, but analysis and dating is first published today in the journal Science. Dr Henshilwood said the patterns were similar to abstract paintings found alongside cave paintings in Europe. But those were much more recent. "They would have needed language - in this case, modern, syntactic language - to have been able to explain to other people in the cave what the meaning of these pieces was.
"Here we have a good indication of an ability to think in the abstract, to think in terms of the past, the present and the future, and that's one of the hallmarks of modern behaviour. People were able to plan."
Anatomically modern humans evolved in Africa about 150,000 years ago - initially a group of perhaps as few as 10,000 who would go on to populate the planet, displacing Neanderthals.
But it has been disputed just when Homo sapiens, so close to us in appearance, began to show the characteristic pat terns of behaviour - art, language, planning, flexible organisation - which made them human. One camp argues this began with relative suddenness 40-50,000 years ago, when Africa's stone age was already old and the colonization of Europe had already begun. Others maintain modern behaviour emerged gradually, much earlier. They have not had good evidence until now.
Use of fire and simple tools is known to go back much earlier, but scientists do not consider this as "modern".
Dr Henshilwood was joined in investigating the artefacts by an international team, including scientists from the Institute of Geography and Earth Sciences in Aberystwyth, whose work was crucial to dating the engravings.
It is not known what their significance was. "Many have made a connection between the deep red of ochre and the blood of menstruation, of puberty, but that's really in the dark realm. We don't know," said Dr Henshilwood.