In the arid expanses of southern Africa, an extraordinary archaeological discovery is challenging our understanding of early human cognition and symbolic thought. Over 60,000 years ago, groups of Homo sapiens inscribed hundreds of ostrich eggshell fragments with intricate geometric engravings. These markings, found across various sites including Diepkloof, Klipdrift in South Africa, and Apollo 11 in Namibia, reveal a level of abstract reasoning and visual planning that propels us far back into the origins of human symbolic behavior.
A groundbreaking study conducted by an interdisciplinary team from the University of Bologna offers unprecedented insights into these ancient artworks. Utilizing methods of geometric and statistical analysis unconventional to archaeology, the researchers demonstrated that these engravings were not haphazard scratches but followed precise geometric principles. Parallelisms, orthogonal intersections, rotations, and systematic repetitions formed a “visual grammar,” a set of abstract rules guiding the creation of these motifs. This discovery reframes the narrative of early human cognitive complexity and abstract thought.
The study focused on 112 ostrich eggshell fragments, meticulously catalogued from three key archaeological sites. By reconstructing the lines, angles, and spatial patterns of each engraving, the researchers identified consistent use of geometric configurations with a dominant presence of right angles and parallel lines. Intricate patterns included hatched bands, grids, and diamond shapes, all arranged following rotational and translational operations. Such precision suggests that the artists possessed a sophisticated mental template before even beginning their etchings—a planning process implying advanced visuo-spatial capabilities.
The archaeological significance of ostrich eggshells extends beyond mere decoration. These containers likely served functional purposes such as water storage, rendering their embellishment even more remarkable. The geometric engravings transcend utilitarian application; they embody a symbolic language where abstract thought was visually encoded. This confluence of practicality and symbolism marks a pivotal cognitive leap in our ancestors’ history, highlighting how early humans began to manipulate signs, not just objects.
Professor Silvia Ferrara, who led the investigation at the University of Bologna’s Department of Classical Philology and Italian Studies, emphasizes the structured nature of these engravings. She articulates that these markings represent more than artistic expression; they are cognitive blueprints outlining mental processes involving spatial organization and abstract reasoning. The engravings are embodiments of the capacity to internally organize visual space according to logical principles, a trait long considered fundamental to the development of symbolic communication.
Further, these geometric patterns manifest hierarchical visual thinking. The phenomenon of “embedding,” wherein signs are nested within one another, created layers of meaning and complexity on limited surfaces. This hierarchical structuring is a hallmark of symbolic systems and prefigures the development of writing and other coded languages. Such cognitive operations—rotation, translation, repetition—demonstrate that these early Homo sapiens engaged in what can be seen as proto-grammatical constructions, an embryonic stage of organized symbolic communication.
The implications of this research extend far into the study of human cognitive evolution. It presents a tangible marker of abstract thinking capabilities developed well before the advent of formal writing systems. The ability to transform simple lines into a coherent system governed by consistent rules invites a reevaluation of when and how humans developed complex symbolic thought. It positions these ancient populations at the forefront of cognitive innovation, illustrating that the roots of geometric reasoning and symbolic art run deeper than previously thought.
Dr. Valentina Decembrini, the first author and a PhD student involved in the project, underscores the significance of this cognitive breakthrough. The emergence of abstract visual systems reveals an innate human trait: the drive to impose order and meaning upon the environment. Through these engravings, early Homo sapiens not only decorated functional objects but also externalized mental constructs into shared visual symbols, paving the way for cultural transmission and communal understanding.
This study also bridges anthropology and cognitive science, offering quantitative rigor rarely applied in archaeological art analysis. By integrating statistical and geometric methodologies, the team reconstructed the engraving processes, identifying underlying patterns imperceptible to the untrained eye. This approach provides a framework for interpreting other prehistoric symbolic artifacts, potentially revising our comprehension of early symbolic behavior across different hominin groups.
Moreover, the research highlights the complex interplay between form and function in early human artifacts. The detailed geometric compositions suggest that these markings were far from random doodles. Instead, they represent deliberate cognitive acts engaging visuospatial planning, abstraction, and hierarchical thinking—traits seen as foundational for language, mathematics, and other cultural technologies central to human societies.
Through this lens, the ostrich eggshell engravings become a powerful symbol of the cognitive revolution that preceded and underpinned human cultural evolution. They reveal that 60 millennia ago, our ancestors were not only surviving but also experimenting with abstract concepts and visual codes, laying the groundwork for the symbolic systems that shape human civilization today.
The study, entitled “Earliest Geometries: A Cognitive Investigation of Howiesons Poort Engraved Ostrich Eggshells,” was published in PLOS One. The interdisciplinary team—comprising Valentina Decembrini, Ludovica Ottaviano, Mattia Cartolano, Enza Elena Spinapolice, and Silvia Ferrara—employed a pioneering analytical framework to reveal cognitive strategies encoded in these ancient artifacts. Their findings illuminate how Homo sapiens of the Howiesons Poort period mastered visual complexity and abstraction, marking a seminal chapter in our cognitive lineage.
This research was conducted within the FIS Advanced project SAPIENCE (Symbols, Preliteracy and Code Evolution), directed by Professor Silvia Ferrara in collaboration with Professor Enza Spinapolice of Sapienza University of Rome. The project aims to trace the evolution of symbolic thought and preliteracy, linking archaeological evidence to the emergence of codes and writing systems. This study of ostrich eggshell engravings stands as a milestone in understanding the dawn of human symbolic cognition.
Subject of Research: People
Article Title: Earliest geometries: A cognitive investigation of Howiesons Poort engraved ostrich eggshells
Web References: http://dx.doi.org/10.1371/journal.pone.0338509
Keywords
Abstract thought, Homo sapiens, archaeological engravings, ostrich eggshells, geometric patterns, cognitive evolution, symbolic behavior, Howiesons Poort, visual grammar, spatial organization, prehistoric art, interdisciplinary research
