A major announcement was made on Sep 10th 2015: the publication of Homo naledi, a new species of the genus Homo discovered in the Dinaledi Chamber of the Rising Star cave system, South Africa.

Naledi is an African name that originates from the Sesotho tribe in southern Africa, meaning ‘star’.

Reconstruction of Homo naledi. Credit: Lee R. Berger

About the hominid

• 1,800 fossil specimens representing at least 15 individuals, spanning the full range of ages from infancy to old age.

• This is the most complete assemblage of fossils from a candidate human ancestor ever found. All body parts are represented, making the Homo naledi sample richer than that of any other early human species such as Homo rudolfensis, Homo habilis, and Homo erectus.

• Average height 1.5 m, weight 45 kg.

• Skull: Primitive, resembling Homo habilis. Size between 466 and 560 cc, compared to H. habilis (510-700 cc), H. erectus (550-1100 cc), and H. floresiensis (426 cc).

• Dentition: Teeth from individuals of different ages. Primitive traits include increasing size towards the back of the jaw, but they are small and simplified, set in lightly built jaws—features considered more modern.

• Postcranial skeleton: Wrists, hands, legs, and feet are similar to those of Neanderthals and modern humans. The curved finger bones suggest climbing ability, while the legs and feet indicate long-distance walking efficiency. The overall body shows similarities to the Homo erectus fossils from Dmanisi.

About the site

• Only hominins seem to have reached the Dinaledi Chamber. Fossil preservation is exceptional: the bones show no cut marks, no breakage, and no evidence of animal activity.

• There is no archaeological evidence of habitation—no tools, no fire traces. The chamber was never open to the surface, and the route to it is extremely difficult. Other animals could not have accessed it.

• The fossils were not transported by water, nor do they show signs of a catastrophic event or scavenging.

• Conclusion: The leading hypothesis is deliberate deposition of bodies, possibly involving some form of burial or ritual, though catastrophic explanations cannot be ruled out. This scenario recalls that of the Sima de los Huesos site (Atapuerca, Spain, 430 ka). However, while the Sima hominins had brain capacities of around 1000 cc, Homo naledi was a small-brained hominin—an unexpected candidate for complex behaviors

• Open questions: Further research must address unresolved issues: How did the hominins reach the chamber? Did the cave have another entrance in the past? How did they use fire? For now, Homo naledi is known only from the Rising Star cave system, at two locations: the Dinaledi Chamber (published in 2015) and the Lesedi Chamber (published in 2017). Was this species restricted to southern Africa?

Dating

• Dating studies published in 2017 and 2021 place the age of H. naledi fossils between 241 and 335 ka—much more recent than early speculations, which suggested around 2 Ma, near the origin of the genus Homo.