Does it seem as if not a day goes by without news concerning yet another ancient human ancestor that may or may not have had sexual relations with humans? Most of these discoveries are tiny bone fragments or environmental DNA (eDNA) – cellular material from skin, feces or other sources – so the discovery of a 250,000-year-old skull of a child of the ancient species known as Homo naledi is a stop-the-presses moment (ask your grandparents what it means). Not only may it reveal more on how we’re related to this species which had both human and non-human traits, the skull was positioned purposefully in what may have been a funeral ritual. Did you say non-human traits? Is this the missing link?
“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.”
Juliet Brophy, lead author of a study of the skull and an associate professor at Louisiana State University, explained in a press release announcing the discovery that the team nicknamed the fossil “Leti” which is short for “letimela” and means “the lost one” in the South African Setswana language. The skull was found with great difficulty in the Rising Star cave where the first Homo naledi fossils were discovered in 2013. They date to the Middle Pleistocene era 335,000–236,000 years ago and the 1,550 fossil specimens have been linked to at least 15 different individuals. Homo naledi were small and had unusually small brains – Leti confirms this (photo here) — but indications are that they could speak, use tools and intermingle with other larger-brained homo species in the Cradle of Humankind. (More photos here.) However, Lee Berger, lead researcher on the study, says Leti was very different from the other hominids at the time.
“Homo naledi remains one of the most enigmatic ancient human relatives ever discovered. It is clearly a primitive species, existing at a time when previously we thought only modern humans were in Africa. Its 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.”
Perhaps the biggest ‘complexifier’ is the location where Leti’s skull was discovered in 2017 – deep within a spiderweb of passages in a narrow one only five inches wide and 31 inches long. It seems obvious the 4-to-6-year-old was carefully and painstakingly placed there for a reason. What was it?
“It is not known whether Leti was buried in the passage or whether her bones were placed there. The situation is very similar to the way Neo, and adult male Homo naledi from the Lesedi Chamber of the Rising Star system, in that he was also found in a narrow passage. However, there have been no remains of Leti’s body found yet. The situation where Leti’s skull was found is very difficult to access, making excavation difficult, but at this stage it appears that only Leti’s skull was in the passage.”
Only the skull … that makes the discovery even more puzzling. But what a skull it is – not only is it the first skull remains of a child of Homo naledi discovered, it has a set of teeth that will help researchers better understand the growth and development of the species.
The more we find, the less we know. Thanks Leti!