What a discovery! 250 000-year

Leti’s skull. Image: Wits University

What a discovery! 250 000-year-old skull of child found in cave near Joburg

Researchers discovered what they are calling the skull of ‘Leti’ – a Homo naledi child discovered in the Rising Star cave system outside Johannesburg.

What a discovery! 250 000-year

Leti’s skull. Image: Wits University

In what is being called an “extraordinary discovery” and possibly “the biggest discovery of the year”, an international team of researchers announced the discovery of a partial skull of a Homo naledi child in the remote depths of the Rising Star Cave in the Cradle of Humankind World Heritage Site near Johannesburg.

A child of darkness

The research – that was led by Professor Lee Berger from Wits University – was published in two separate papers in the Open Access journal, PaleoAnthropology, and saw the team of 21 researchers from Wits University and thirteen other universities working together to find parts of the skull and teeth of the child that died almost 250 000 years ago when it was approximately four to six years old.

According to Wits, the child was found in an extremely remote passage of the Rising Star Cave System, some 12 meters beyond the Dinaledi Chamber, the original site of the discovery of the first Homo naledi remains that were revealed to the world in 2015.

The richest site for fossil hominins on the continent of Africa

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.

“This makes this the richest site for fossil hominins on the continent of Africa and makes naledi one of the best-known ancient hominin species ever discovered,” says Professor John Hawks, a biological anthropologist and lead author of a previous study on the fossil skeleton of a male naledi nicknamed “Neo” that was also found at the Rising Star cave.

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Meet Leti, a Homo naledi child discovered in the Rising Star Cave System that yielded Africa’s richest site for fossil hominins. Image: Wits University

Leti’s skull

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.

The team have named the child “Leti” meaning “the lost one”. Leti’s skull consists of 28 skull fragments and six teeth and when reconstructed shows the frontal orbits, and top of the skull with some dentition. 

“There were no replicating parts as we pieced the skull back together and many of the fragments refit, indicating they all came from one individual child,” says Dr Darryl de Ruiter, a palaeoanthropologist who previously led a study of the adult skull of Homo naledi and who is a co-author on the paper.

“This is the first partial skull of a child of Homo naledi yet recovered and this begins to give us insight into all stages of life of this remarkable species,” says Professor Juliet Brophy, who led the study on Leti’s skull and dentition.

A reconstruction of the skull of Leti in the hand of Professor Lee Berger © WITS UNIVERSITY
Leti’s skull. Image: Wits University

An extremely rare find

The discovery is said to be an extremely rare find in the fossil record as juvenile remains tend to be thin and extremely fragile.

“Having skull remains associated with teeth of the same individual is extremely important for understanding the growth and development of this species,” says Christopher Walker, an expert in growth and development.

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,” says Dr Debra Bolter, a co-author on the paper and a specialist in growth and development. “The size of Leti’s brain makes it very comparable to adult members if the species found so far,” says Bolter.

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Professor Lee Berger from Wits University. Image: Wits University

It has yet to be established how old Leti’s remains are. However, other fossils of Homo naledi were found in the nearby Dinaledi Chamber and is dated between 335 and 241 thousand years ago.

Image: Wits University

Tebogo Makhubela, part of the geological team investigating the discovery believes that it is likely that Leti is from a similar period, based on preservation and proximity.

You can read more about the team and the discovery over here.