An international team of scientists has substantially increased the age at which we can trace the emergence of modern culture, all thanks to the San people of Africa.
Artifacts from Border Cave. 1–8: implements made on warthog or bushpig lower canines, and 9-12: notched bones (d’Errico F et al / PNAS)
The results by the team, consisting of scientists from South Africa, France, Italy, Norway, the USA and Britain, are published in two papers online in the Proceedings of the National Academy of Sciences (paper1, paper2).
“The dating and analysis of archaeological material discovered at Border Cave in South Africa, has allowed us to demonstrate that many elements of material culture that characterize the lifestyle of San hunter-gatherers in southern Africa, were part of the culture and technology of the inhabitants of this site 44,000 years ago,” said Dr Lucinda Backwell, a senior researcher in paleoanthropology at the Wits University’s Bernard Price Institute for Paleontological Research and co-author of both papers.
A key question in human evolution is when in prehistory human cultures similar to ours emerged? Until now, most archaeologists believed that the oldest traces of San hunter-gatherer culture in southern Africa dates back 10,000, or at most 20,000 years.
Now the team has dated and directly analyzed objects from archaeological layers at Border Cave. Located in the foothills of the Lebombo Mountains in KwaZulu-Natal, South Africa, the site has yielded exceptionally well-preserved organic material.
Dr Backwell said their results have shown without a doubt that at around 44,000 years ago the people at Border Cave were using digging sticks weighted with perforated stones, like those traditionally used by the San.
“They adorned themselves with ostrich egg and marine shell beads, and notched bones for notational purposes. 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,” Dr Backwell explained.
Chemical analysis of residues on a wooden stick decorated with incisions reveals that, like San objects used for the same purpose, it was used to hold and carry a poison containing ricinoleic acid found in castor beans. This represents the earliest evidence for the use of poison.
A lump of beeswax, mixed with the resin of toxic Euphorbia, and possibly egg, was wrapped in vegetal fibers made from the inner bark of a woody plant. “This complex compound used for hafting arrowheads or tools, directly dated to 40,000 years ago, is the oldest known evidence of the use of beeswax,” Backwell said.
Warthog tusks were shaped into awls and possibly spear heads. The use of small pieces of stone to arm hunting weapons is confirmed by the discovery of resin residue still adhering to some of the tools, which chemical analysis has identified as a suberin (waxy substance) produced from the sap of Podocarpus (yellowwood) trees.
Artifacts from Border Cave. 1–7: bone awls and points, 8–21: beads of ostrich eggshells, 22-23: Nassarius kraussianus beads, 24: lump of organic material bound with vegetal fibers, 25: digging stick, 26: poison applicator. Scale bars: 1 cm (d’Errico F et al / PNAS)
The study of stone tools found in the same archaeological layers as the organic remains, and from older deposits, shows a gradual evolution in stone tool technology. Organic artifacts, unambiguously reminiscent of San material culture, appear relatively abruptly, highlighting an apparent mismatch in rates of cultural change.
This finding supports the view that what we perceive today as ‘modern behavior’ is the result of non-linear trajectories that may be better understood when documented at a regional scale.
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Bibliographic information:
d’Errico F et al. 2012. Early evidence of San material culture represented by organic artifacts from Border Cave, South Africa. PNAS, published online before print July 30, 2012; doi: 10.1073/pnas.1204213109
Villa P et al. 2012. Border Cave and the beginning of the Later Stone Age in South Africa. PNAS, published online before print July 30, 2012; doi: 10.1073/pnas.1202629109
