Evidence of early human use of geometric concepts in prehistoric art has surfaced in southern Africa, revealed in a series of archaeological discoveries that point to complex patterns and repetition in ancient etchings on ostrich eggshells.
The remarkable finds, uncovered at a series of archaeological sites throughout southern Africa, are believed to have been engraved by early Homo sapiens in the regions close to 60,000 years ago—far earlier than previous examples of organized markings suggestive of the use of geometric rules.
The new findings were made by a research team based at the University of Bologna and reported in a study published in PLOS One.
Echoes of Early Geometry?
As the branch of mathematics that involves spatial properties such as shape, size, and relative position, it is known that the Ancient Babylonians began using geometrical calculations to track the movement of planets like Jupiter at least 1,400 years earlier than previously believed.
To compare the etchings uncovered by the team led by Silvia Ferrara, a Professor at the University of Bologna’s Department of Classical Philology and Italian Studies, to the capabilities of the ancient Babylonians would be off base. However, evidence of more rudimentary geometric thinking—obvious repetition, use of parallel lines, presence of angles (orthogonality), and other distinctive geometric organization—in the ancient African discoveries is hard to ignore.
“These signs reveal a surprisingly structured, geometric way of thinking,” Ferrara said in a statement provided to the University of Bologna’s Unibo Magazine.
“We are talking about people who did not simply draw lines,” Ferrara adds, “but organized them according to recurring principles—parallelisms, grids, rotations, and systematic repetitions: a visual grammar in embryo.”
An Ancient Tale Told on Ostrich Eggs
Ferrara and her team have hypothesized that the primary purpose of these ostrich eggs was to transport water. Probing more deeply into the curious markings that covered many of the eggshell fragments recovered from a trio of southern African archaeological sites, the team conducted a quantitative and systematic investigation of 112 samples.
Employing statistical analysis and geometric methods of investigation that had never been used for such artifacts before, Ferrara and her team reconstructed the lines and designs on the eggshells.
The results were surprising: Ferrara’s team discovered that more than 80% of the etchings they analyzed showed signs of “coherent spatial regularities” and evidence of repetitive orthogonality, with angles near 90° and angles resulting from the convergence of groups of lines drawn parallel to each other.
Ferrara and the team also point to the complexity in several of the etchings, which include repetitive hatched bands, geometric shapes such as simple parallelograms, grid-like motifs, and other features, which they argue as evidence of complex cognitive operations. Beyond the etchings themselves, the markings reveal evidence of rotation, translation, and repetition by the ancient designers, who displayed remarkable capabilities 60,000 years ago at sites in South Africa and Namibia.
Geometric “Mastery” in Ancient Southern Africa
“These engravings are organized and consistent,” Ferrara said, “and show mastery of geometric relationships.”
“There is not only a process of repeating signs: there is real visuo-spatial planning, as if the authors already had an overall image of the figure in mind before engraving it,” she adds.
Presently, the meaning or intention behind the markings remains unknown. However, while such questions may likely remain unanswered, the deeper evidence these ancient markings provide is of even greater significance: clear signs of cognitive capabilities by the ancient artists, who displayed an ability to construct a structured configuration based on geometric rules—all of which is strongly suggestive of abstract thought.
Such cognitive capabilities would have played an important role in the overall development of the human mind, eventually giving rise to written language, more complex tool use, art, and, eventually, the kinds of spatial awareness that would lead to the development of geometry and other branches of mathematics.
Valentina Decembrini, PhD student at the University of Bologna’s Department of Classical Philology and Italian Studies and the recent study’s first author, said the analysis she and her colleagues conducted clearly reveals that artists etching ostrich eggshells in Africa 60,000 years ago “already possessed a remarkable ability to organize visual space according to abstract principles.”
“Transforming simple forms into complex systems by following defined rules is a deeply human trait that has characterized our history over millennia,” Decembrini added, “from the creation of decorations to the development of symbolic systems and, ultimately, writing.”
The team’s recent study, “Earliest Geometries. A Cognitive Investigation of Howiesons Poort Engraved Ostrich Eggshells,” appeared in PLOS One.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.