05-09-2017

South African fossil discovery sheds new light on human relative

Earth.com staff writer

Researchers working in a South African cave have discovered more remains of a newfound human relative called Homo naledi.

The latest discovery, which occurred in 2013 and was announced Tuesday in the journal eLife helps round out the picture of Homo naledi, who shared the landscape with modern humans between 226,000 and 335,000 years ago, the University of Wisconsin-Madison said

The remains of at least two adults and a child, including a complete skull, were found in a South African cave system known as Rising Star, the university said. Nearby in the same cave system, researchers earlier found the first Homo naledi fossils representing at least 15 individuals of various ages.

“This likely adds weight to the hypothesis that Homo naledi was using dark, remote places to cache its dead,” said University of Wisconsin-Madison anthropologist John Hawks.

“What are the odds of a second, almost identical occurrence happening by chance?”

The skull of one of the newly found skeletons has much of the face, including the delicate bones of the inner eye region and nose, Hawks said. It has a complete collarbone and a near-complete femur, which help to confirm what scientists suspected about the size and stature of Homo naledi, and that it was both an effective walker and climber.

“We finally get a look at the face of Homo naledi,” said Peter Schmid, who holds a joint appointment at the University of Witwatersrand and the University of Zurich, and who spent hundreds of hours reconstructing the fragile bones of the skull.

Earlier, researchers in a deep Spanish cave known as Sima de los Huesos uncovered evidence that Neanderthals were caching the bodies of their dead companions 400,000 years ago.

“What is so provocative about Homo naledi is that these are creatures with brains one third the size of ours,” Hawks says. “This is clearly not a human, yet it seems to share a very deep aspect of behavior that we recognize, an enduring care for other individuals that continues after their deaths. It awes me that we may be seeing the deepest roots of human cultural practices.”

Researchers believe more remains will be recovered as excavations in the cave system continues. The new chamber is very difficult to access, requiring excavators to crawl, climb and squeeze their way in pitch dark to the fossil cache, the university said.