By Thomas H. Maugh II
July 30, 2012, 1:54 p.m.
|Objects found in the archaeological site called Border Cave include a) a wooden digging stick; b) a wooden poison applicator; c) a bone arrow point decorated with a spiral incision filled with red pigment; d) a bone object with four sets of notches; e) a lump of beeswax; and f) ostrich eggshell beads and marine shell beads used as personal ornaments. (Francesco d’Errico and Lucinda Backwell/ July 30, 2012)|
That blossoming of technology and art occurred at roughly the same time that modern humans were migrating fromAfrica to Europe, where they soon displaced Neanderthals. Many of the characteristics of the ancient culture identified by anthropologists are still present in hunter-gatherer cultures of Africa today, such as the San culture of southern Africa, the researchers said.
The new evidence was provided by an international team of researchers excavating at an archaeological site called Border Cave in the foothills of the Lebombo Mountains on the border of KwaZulu-Natal in South Africa and Swaziland. The cave shows evidence of occupation by human ancestors going back more than 200,000 years, but the team reported in two papers in the Proceedings of the National Academy of Sciences that they were able to accurately date their discoveries to 42,000 to 44,000 years ago, a period known as the Later Stone Age or the Upper Paleolithic Period in Europe.
Among the organic — and thus datable — artifacts the team found in the cave were ostrich eggshell beads, thin bone arrowhead points, wooden digging sticks, a gummy substance called pitch that was used to attach bone and stone blades to wooden shafts, a lump of beeswax likely used for the same purpose, worked pig tusks that were probably use for planing wood, and notched bones used for counting.
“They adorned themselves with ostrich egg and marine shell beads, and notched bones for notational purposes,” said paleoanthropologist Lucinda Blackwell of the University of Witwatersrand in South Africa, a member of the team. “They fashioned fine bone points for use as awls and poisoned arrowheads. One point is decorated with a spiral groove filled with red ochre, which closely parallels similar marks that San make to identify their arrowheads when hunting.”
The very thin bone points are “very good evidence” for the use of bows and arrows, said co-author Paola Villa, a curator at the University of Colorado Museum of Natural History. Some of the bone points were apparently coated with ricinoleic acid, a poison made from the castor bean. “Such bone points could have penetrated thick hides, but the lack of ‘knock-down’ power means the use of poison probably was a requirement for successful kills,” she said.
The discovery also represents the first time pitch-making has been documented in South Africa, Villa said. The process requires burning peeled bark in the absence of air. The Stone Age residents probably dug holes in the ground, inserted the bark, lit it on fire, and covered the holes with stones, she said.