In 2000, a team led by paleoanthropologist Brigitte Senut discovered a fossil in the Tugen Hills of the Baringo district that they named Orrorin tugenensis. The fossil was dated to approximately six million years ago, making it one of the oldest potential human ancestors ever found.
The discovery supported the hypothesis that bipedalism, walking on two legs, evolved in Africa much earlier than previously thought. Kenya had already given the world Turkana Boy and Homo habilis.
Now it was offering evidence of something even older, a creature that might stand at the very root of the human family tree.