This ancient fossil could rewrite the story of human origins

Scientists may have cracked the case of whether a seven-million-year-old fossil could walk upright. A new study found strong anatomical evidence that Sahelanthropus tchadensis was bipedal, including a ligament attachment seen only in human ancestors. Despite its ape-like appearance and small brain, its leg and hip structure suggest it moved confidently on two legs. The finding places bipedalism near the very root of the human family tree.