A recent discovery is shaking the foundations of what scientists thought they knew about early human intelligence. Deep within the Rising Star cave system in South Africa, researchers believe that Homo naledi, a small-brained human ancestor, may have buried their dead and created symbolic carvings more than 250,000 years ago. This revelation raises critical questions about the evolution of cognitive abilities and challenges long-held assumptions about the connection between brain size and complex behavior.
A species that defies classification
Discovered in 2013, Homo naledi is a hominin species that displayed an unusual combination of ancient and modern traits. Standing approximately 1.5 meters tall and weighing around 45 kilograms, it had a brain roughly one-third the size of a modern human’s—comparable to that of a chimpanzee.
Despite this, Homo naledi had human-like hands and feet, walked upright, and lived in deep cave systems where remains of at least 15 individuals have been found, making it one of the best-documented extinct hominins.
This mixture of features initially baffled researchers, but the discovery of possible cultural behaviors adds another layer of intrigue. New evidence suggests that this species may have participated in burial practices once thought to be exclusive to Homo sapiens and Neanderthals.
Evidence of intentional burials
Initial studies in 2017 hinted that Homo naledi might have disposed of their dead in an intentional manner. This idea gained momentum in 2023, when an international team led by paleoanthropologist Lee Berger announced findings of two shallow, oval-shaped pits within the cave system.
These pits contained skeletal remains preserved in anatomical position, strongly suggesting that the bodies were carefully placed in these graves rather than scattered by natural events.
In one instance, a stone tool was found near a skeleton, potentially serving as a grave offering. If these interpretations hold up to further scrutiny, they would significantly push back the earliest known evidence of mortuary behavior by over 100,000 years—and challenge the notion that such practices were unique to larger-brained hominins.
Carvings that hint at symbolic thinking
In addition to the graves, researchers uncovered abstract carvings etched into the walls just above the burial sites. The markings include lines and patterns that resemble hashtags and appear to have been deliberately carved into the stone. What makes these engravings even more compelling is that the rock surfaces appear to have been prepared before the markings were made, implying intent and forethought.
For Berger and his team, the placement of these carvings—directly above the graves—suggests they may have held symbolic or ritual significance. If accurate, this would represent the oldest known example of symbolic thought by any hominin, raising the possibility that such behavior did not require a large brain to emerge.
A growing scientific debate
While the findings are remarkable, they remain controversial within the scientific community. Anthropologist Sheela Athreya from Texas A&M University has voiced skepticism, cautioning that the researchers might be drawing conclusions too quickly.
According to her and other critics, the bone placement could be explained by natural geological processes like underground water movement or sediment displacement. Similarly, they argue that the carvings may not be intentional at all, but rather the result of natural abrasion or rockfall.
In response, Berger’s team published a comprehensive 250-page study detailing the site and its findings. This includes a full reconstruction of the proposed burial and engraving process. While the publication has convinced some in the field, many experts are calling for independent verification and additional excavations before accepting the claims.
If proven, these discoveries could radically change the way scientists define intelligence, culture, and what it means to be human. But for now, the debate continues—centered around a small-brained ancestor that may have been far more sophisticated than anyone previously imagined.
