Homo naledi, a human ancestor that lived about 300,000 years ago, probably ate food that was hard or gritty, Bruce Bower writes for Science News. The study was published in the American Journal of Physical Anthropology.
Why it matters: Naledi is known for its startling mix of modern and primitive traits and the fossils' relatively recent age: it may have overlapped with modern humans. Some think the chips, combined with H. naledi's small tooth size, could suggest it had a flexible diet, like modern humans. It's also another way H. naledi are unique among non-human primates, since no non-human ape species so far, fossil or otherwise, have shown this level of dental chipping.
What they found: The researchers looked at 126 fossil teeth from at least 15 individuals discovered in 2015 in one of the largest hominid fossils finds ever, and compared the chipping rates to other apes (fossil and modern). They found 44% of teeth were chipped, a higher number than any other ape species included in the analysis, ancient or modern. Chipping occurs when animals have a diet of hard foods like nuts or grit-covered foods dug up from the ground, like roots and tubers. The chips were in places consistent with damage from eating, not damage from tool use.