Washington, March 3 (ANI): Scientists have said that a cache of ostrich eggshells engraved with geometric designs demonstrates the existence of a symbolic communication system around 60,000 years ago among African hunter-gatherers.
The unusually large sample of 270 engraved eggshell fragments, mostly excavated over the past several years at Diepkloof Rock Shelter in South Africa, displays two standard design patterns, a team led by archaeologist Pierre-Jean Texier of the University of Bordeaux 1 in Talence, France, told Discovery News.
Each pattern enjoyed its own heyday between approximately 65,000 and 55,000 years ago, the investigators reported.
Researchers already knew that the Howiesons Poort culture, which engraved the eggshells, engaged in other symbolic practices, such as engraving designs into pieces of pigment, that were considered to have been crucial advances in human behavioral evolution.
"But the Diepkloof finds represent the first archaeological sample large enough to demonstrate that Stone Age people created design traditions, at least in their engravings," Texier said.
Evidence of intentionally produced holes in several Diepkloof eggshells indicates that ancient people made what amounted to canteens out of them, a practice that researchers have documented among modern hunter-gatherers in southern Africa.
The engraved patterns probably identified the eggshells as the property of certain groups or communities, Texier proposed.
"The Diepkloof engravings were clearly made for visual display and recognized as such by a large audience comprising members of a community, and probably members of related communities," according to University of Bordeaux archaeologist Francesco d'Errico.
Eggshell fragments from the oldest sediment layers at Diepkloof display a hatched-band motif.
These engravings consist of two long, parallel lines intersected by varying numbers of short lines. Some specimens contain one hatched band, while others display remnants of two or three.
"Engravers always fashioned parallel lines first and then inserted regularly spaced intersecting lines," Texier said.
Eggshells from younger soil layers at Diepkloof contain patterns consisting of deeply engraved, parallel lines that sometimes converge or intersect.
One eggshell fragment from these layers exhibits a different pattern - slightly curved horizontal lines that cross a central, vertical line.
"Of the many Howiesons Poort sites in southern Africa that have yielded ostrich eggshells, only Diepkloof shows evidence of stylistic engraving traditions," Texier said.
Along with perforated sea shells and other personal ornaments previously excavated in Africa and the Middle East, these discoveries show that items holding symbolic meaning were made ore than 60,000 years ago by both modern humans and Neanderthals. (ANI)