A colorful pebble bearing a sequence of linear incisions may be the world's oldest engraving.
The object, which will be described in the April issue of the Journal of Archaeology, dates back about 100,000 years ago and could also be the world’s oldest known abstract art. It was recovered from Klasies River Cave in the Eastern Cape Province of South Africa.
“Associated human remains indicate that the engraved piece was certainly made by Homo sapiens,” co-author Riaan Rifkin of the University of Witwatersrand’s Institute for Human Evolution told Discovery News.
Rifkin and colleagues Francesco d’Errico and Renata Garcia Moreno performed extensive non-invasive analyses of the object. Methods like X-ray fluorescence and microscopic analysis enabled the researchers to examine every minute detail of the ochre pebble, which appears to have split off from a once larger piece.
The scientists conclude that humans intentionally made the sub-parallel linear incisions on the Middle Stone Age pebble.
“Upon engraving the piece with a sharp lithic implement, it is likely to have produced a markedly bright and dark red-maroon powder,” Rifkin said. “The design may therefore have been strikingly visible shortly after it was produced.”
Ochre is a mineral-rich, naturally tinted clay that primarily consists of hydrated iron oxide. Ochre was among the earliest pigments used by humans and possibly other hominids for artistic purposes. Some even refer to it as the caveman's "crayon."
The Klasies River object measures close to 3 inches in length and contains a series of seven “deep broad engraved lines and several, about 16 or so, narrower and somewhat shallower linear features,” Rifkin said. “The fragment is a remnant of a formerly semi-circular ochre pebble that likely contained a much more extensive engraved design on its surface.”
Of particular interest now is whether or not the engraver made the design with symbolic intent. Use of symbols and meaningful images is thought to have been a significant breakthrough in human development. Language, math and countless other studies are tied to this basic skill, in addition to improved communication. To this day, art permits communication of identity and other things among diverse cultures.
Both linear and crosshatch engraved patterns may have been common thousands of years ago. Similar designs appear on engraved ochres from Blombos Cave, also in South Africa, and on ostrich eggshell fragments found in the Diepkloof Rock Shelter in the Western Cape Province. Some of these, and other, similar objects may even predate the Klasies River pebble, but studies on them are ongoing.
“The employment of red ochre for symbolic purposes likely played an important role in mediating increasingly complex social relations that emerged during the Middle Stone Age,” Rifkin explained.
Christopher Henshilwood, a researcher at the University of Witwatersrand, did not work on this study, but he has examined other very early probable engravings. For example, he studied abstract markings of another piece of ochre dating to around 70,000 years ago.
In that case, the engraving consisted of a more complex geometric pattern that looks like the letter “X” repeated in a connected series.
The possible meaning of these lines remains a mystery, “but they are symbols that I think could have been interpreted by those people as having meaning that would have been understood by others,” Henshilwood said.
At present, Rifkin and his team are studying 30,000-year old cave art from Africa. So far, they have determined that the abstract images depict a zebra, a rhino and a half human-half cat therianthorpe.