more on those items from Blombos Cave – a case for scepticism

75 000 year old shells claimed as beads – Blombos Cave, South Africa

I was arguing a few days ago on 17 April [Link] that the case for these shells being evidence of a modern human mentality was fragile, to say the least, and that the anthropologist leading the excavation that found them was probably under pressure to find a good story – he certainly has a pet theory that modern behavior started first in South Africa, in places like his own site – “there was a bead tradition in the middle Stone Age”.

A shell claimed to show signs of wear from being strung on a cord – Henshilwood

Here is more discussion, today in the Boston Globe [Link]

First, building the story from the few beads –

Alison Brooks, head of the anthropology department at George Washington University in Washington, said the beads suggest that the people of the time had a social structure, and reason to interact with people they didn’t know.

“You don’t need to symbolize your status if you never meet any strangers in a tiny, restricted social group. Everyone you meet already knows you,” Brooks said. But when your social group is larger, “you need to symbolize to strangers or newcomers that, for example, you are married — with a long string of beads, or special hairstyle — that you are not available, a widow, or an important leader.” In addition, “ornaments also figure prominently as gifts in exchange networks, which are important for hunter-gatherers to maintain against the risk of environmental downturns,” Brooks said.

And now Richard Klein, with a sceptical attitude much more like my own –

Anthropologist Richard G. Klein, who has also worked extensively at excavations in South Africa, said he thinks the shells could be 75,000 years old …

MS – there are some disputes over the dating technique – optically-stimulated luminescence

… but he’s not yet convinced they were beads. The holes might have been an accident of nature, rather than man-made.

“It seems strange that the perforations [in the shells] show no wear or marks from pressing against cord or string,” said Klein, a professor at Stanford University, adding that he wishes Henshilwood had addressed that point in his article.

Klein said he’s also concerned that the finds at Blombos Cave are similar to finds in only two or three African sites …

MS – so much for Henshilwood’s “bead tradition”

… while there are at least 40 other sites of the same age that don’t show similar intellectual development.

The reason bead-making and other symbol-making became commonplace “is probably because the behaviors they reflect greatly enhanced survival and reproduction, and this makes it hard to understand why they would remain rare for so long before 40,000 years ago,” Klein said, adding that art became a universal human experience at that point. “My view is that the occurrences before 40,000 years ago are the kind of noise that is inevitable in the archeological record.”

I like this notion of noise – more on it and Michel Serrres another day …