A reconstruction of Homo naledi’s head by paleoartist John Gurche, who spent some 700 hours recreating the head from bone scans. The find was announced by the University of the Witwatersrand, the National Geographic Society and the South African National Research Foundation and published in the journal eLife. (Photo by Mark Thiessen/National Geographic)A new species of human relative, called Homo naledi, has been discovered deep in a cave in South Africa, it was announced Thursday morning at a press conference in Johannesburg. Three men who led the expedition took part in a Q & A with the National Geographic Society about how the fossils were found, their excavation and their two-year analysis by teams of international experts as to their place in human evolution. Below is a selection of those questions and answers from Lee Berger, an archaeologist and the leader of the expedition, John Hawks, an anthropologist and Paul Dirks, a geologist:
1) Why is the combination of features in naledi unusual or unexpected?
Until recently, most anthropologists believed that brain size and tool use emerged together with smaller tooth size, higher-quality diet, larger body size and long legs. In this view, transformations in the body in early Homo were tied to changes in behaviour that influenced diet and the brain. H. naledi shows that these relationships are not what anthropologists expected. It has small teeth and hands that seem to have been effective for toolmaking but also a small brain. It has long legs and humanlike feet but also a shoulder and fingers that seem effective for climbing
What happens if H. naledi is very old? Or very young?
If it turns out that H. naledi is old, say older than around 2-million-years, it would represent the earliest appearance of Homo that is based on more than just an isolated fragment. On the other hand, if it turns out that H. naledi is young, say less than 1-million-years old, it would demonstrate that several different types of ancient humans all existed at the same time in southern Africa, including an especially small-brained form like H. naledi. Given its primitive skeletal adaptations, this might have profound implications for the development of the African archaeological record. It would also have profound implications for our understanding the origins of complex behaviours previously thought to arise only with the origins of hominins not very different from our own …Read More