The first partial skull of a Homo naledi child, Leti, has been found in a remote passage of the Rising Star cave, in Johannesburg, by a team of international researchers led by University of the Witwatersrand's Professor Lee Berger.
Two papers have been written about the discovery of parts of the skull and teeth of the child that died almost 250 000 years ago when it was about four to six years old.
The child’s skull was found alone and no remains of its body have been recovered.
The child was found about 12 meters beyond the Dinaledi Chamber, the original site of discovery of the first Homo naledi remains that were revealed in 2015.
Leti’s brain size is estimated at around 480 to 610 cubic centimetres. “This would have been around 90% to 95% of its adult brain capacity,” said co-author on the paper and a specialist in growth and development Debra Bolter.
“The size of Leti’s brain makes it very comparable to adult members of the species found so far,” she added.
The team named the child “Leti” after the Setswana word “letimela” meaning “the lost one”.
“It is clearly a primitive species, existing at a time when previously we thought only modern humans were in Africa. It’s very presence at that time and in this place complexifies our understanding of who did what first concerning the invention of complex stone tool cultures and even ritual practices,” said Berger.
Almost 2 000 individual fragments of more than two dozen individuals at all life stages of Homo naledi have been recovered since the Rising Star cave system was discovered in 2013.
The skull of the child presented in the current study was recovered during further work in the cramped spaces of the cave in 2017.
The child’s skull was found alone, and no remains of its body have been recovered.
Since its discovery, the Rising Star cave system has become one of the most prolific sites of discovery for hominin fossils in the world.
Berger says that work is continuing throughout the cave system and that soon new discoveries are likely to shed further light on whether these chambers and passages are in fact a burial ground of Homo naledi, as the team originally hypothesised.