Paleoanthropologists have once again sparked a debate after suggesting that a long-extinct human relative may have buried its dead more than 120,000 years before modern humans started funerary practices.
Led by anthropologist Lee Berger, PhD, a director and research professor at the University of the Witwatersrand (Wits University) in South Africa, the researchers recently published their new findings on the Rising Star cave system.
Located near Johannesburg, the deep and hard-to-reach cave holds the fossilized remains of at least 15 Homo naledi individuals, a short and small-brained hominin species who lived between 241,000 and 335,000 years ago.
Following years of dispute with skeptics, who argued that this modern humans’ distant relative was incapable of such complex behaviors, the scientists have now published a peer-reviewed paper potentially demonstrating the opposite.
For the study, the team reexamined the alleged burial site, which they believe is the oldest known and addressed earlier criticisms. They argued that South Africa’s ‘Cradle of Humankind’ may hold some of the earliest evidence of burial practices.
The H. naledi controversy
The Rising Star cave system was discovered by in September 2013 by cavers Rick Hunter and Steve Tucker. Berger who was working with them at the time in order to identify new fossil sites, led the subsequent excavation and research.
His team found numerous fossil bones belonging to what they identified as a new species and excavated over 1,550 fossil parts from the cave. In 2015, they called it Homo naledi, meaning ‘star’ in the local Sotho language.
Later that year, Berger claimed that the remains were intentionally placed in the cave, hinting the species may have engaged in deliberate burial practices.
Berger based his claim on the fossils being found in narrow, pitch-dark chambers, far from natural entrances or evidence of animal activity. He also presented it in a 2023 Netflix documentary series called ‘Unknown: Cave of Bones.”
Credit: Wits University/John Hawks
However, the evidence was largely circumstantial as critics pointed to several alternative explanations. Some suggested the bodies fell through a vertical shaft or were gradually swept in by water or sediment.
In 2024, researchers led by Kimberly Foecke, PhD, an anthropologist at Virginia’s George Mason University, carried out a new analysis on the findings. They found that Berger’s conclusions are insupportable based on the available evidence.
“We see so often flashy shows with charismatic archaeologists presenting huge claims about the past, but we must hold scientists who communicate with the public accountable to the science itself and ensure that we as a field are doing good work,” Foecke said, at the time.
Now, in an bid to address ongoing criticism, Berger and his team once again put forward what they argue that the individuals were deliberately placed deep within the ‘Cradle of Humankind World Heritage Site’ cave.
Rewriting burial history
In the new paper, Berger’s team explained that the bodies became encased in sediment shortly after entering the cave system in at least three locations. This, according to the study, rules out natural causes like water or gravity.
“That approach to the evidence may have seemed conservative, but the current study suggests that it was a mistake to assume that H. naledi was not itself involved in reworking the sediments,” the team elaborated.
Credit: John Hawks/University of Wisconsin-Madison
They further argued that none of the previously proposed natural processes, such as gravity, sediment slumping, downslope movement or slow accumulation, can account for the position and context of the fossil remains in the subsystem.
“Here for the first time, we have considered the hypothesis that Homo naledi was directly involved in the burial process of bodies,” the scientists continued. “This hypothesis explains many aspects of the data from these skeletal remains and sediments that were previously left unexplained.”
The peer-reviewed paper has been published in the journal eLife.