A child’s ancient bones deepen the mystery of an enigmatic human parent
Stuck in a narrow crevice about 150 feet underground in South Africa’s Rising Star cave system, Becca Peixotto squeezed between rock faces to make her way around a bend. Inch by inch, she squirmed in the winding passage, almost turning upside down to reach a small ledge where a scientific treasure awaited: the teeth and bone fragments of a child who lived long ago. 240,000-year-old, an enigmatic human relative known as the Homo naledi.
The discovery adds to nearly 2,000 bones and teeth from H. naledi recovered from Rising Star since cavers stumbled upon the first fossils in 2013. The child’s remains – estimated to have died between four and six years old – include six teeth and 28 skull fragments.
None of these finds have been easy, thanks to terrifying vertical drops and compressions so tight that cavers have to breathe out to compress their rib cages. But the recent contortionist movements required by Peixotto, an archaeologist at American University, Washington, DC, and members of his team have been among the most difficult to date.
The labyrinthine adventure to uncover the remains of the child, nicknamed “Leti” after the setswana word meaning lost, highlights a nagging question about these mysterious human parents: how and why did they venture so deep into this world. dark and winding cave?
“No one involved in this had any expectations that we were going to find naledi bones in these situations, “says John Hawks, a paleoanthropologist at the University of Wisconsin-Madison.” We grow in places that are yards and yards in impossible passages. “
The discovery of the child, described in a new study published in the journal PaleoAnthropology, was part of an effort in 2017 and 2018 to explore the deeper parts of the cave. The team mapped over 1,000 feet of new passages and described the maze-like system in a second study. The work revealed only one entrance to the larger cave system in the Dinaledi subsystem, where most H. naledi remains were found. The last remains are the deepest ever found in the subsystem, deposited more than thirty meters from its opening.
Findings suggest the remains may have been deliberately brought in by others H. naledi as a means of intentionally disposing of their dead, suggest the study authors. “We see no other reason why this little child’s skull is in an extremely difficult to reach and dangerous position,” said Lee Berger, leader of the Rising Star expedition, a paleoanthropologist at the University of South Africa. Witwatersrand and National Geographic explorer. , during a press conference on the discovery.
Yet some scientists who were not part of the study are not yet convinced. Whether H. naledi transported their dead to the cave is of great importance to paleoanthropologists and archaeologists. Such intentional treatment of the deceased involves a level of cultural complexity once considered unique to our species.
“Our reaction to death, our love for other people, our social ties with them, how much do they depend on being human?” Hawks wonders.
The geological jungle gymnasium
H. naledi ‘The bewildering mix of modern and ancient features rocked scientists after the species’ discovery was announced in 2015, showing that human evolution is more complex than previously thought. But one of the most amazing things about these tiny hominids is how hard their remains were to retrieve, and therefore how hard it must have been for them to venture so deep into the cave. .