THE shards of stone pictured, which have an average length of about 30mm, or 1.2 inches, may provide an insight into the evolution of the human psyche. They were discovered at Pinnacle Point, on South Africa’s southern coast, by Kyle Brown of the University of Cape Town and Curtis Marean of Arizona State University, and they are estimated to be 71,000 years old.
Such shards are known as microliths. They are made by heating a suitable lump of rock in a fire, and then bashing it, in order to flake pieces off its surface. They are believed to have been employed mainly as arrow heads—and were so used in Scandinavia as recently as 9,000 years ago.
From about 40,000 years ago microliths are common. Before that date, only one set of examples, from about 60,000 years ago, had been found. This fact has been used for support by those who think the human psyche evolved separately from, and more recently than, the physique of Homo sapiens.
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