Archaeologists in Kenya have dug up some of the oldest stone tools ever used by ancient humans, dating back around 2.9 million years, the BBC reports.
It is evidence that the tools were used by other branches of early humans, not just the ancestors of Homo Sapiens.
The tools were used to butcher hippos and pound plant materials like tubers and fruit, the researchers said.
Two big fossil teeth found at the site belong to an extinct human cousin, known as Paranthropus.
Scientists had previously thought that Oldowan tools, a kind of simple stone implement, were only used by ancestors of Homo Sapiens, a grouping that includes our species and our closest relatives.