What a Fossilized Hand Says About the Last Common Ancestor Between Humans and Chimpanzees

More than 1 million years before the early hominin known as Lucy was striding across the Afar region of Ethiopia, the lesser-known Ardipithecus ramidus roamed approximately the same area. Now, a team of anthropologists have looked at the 4.4 million-year-old fossilized hand of one specimen (affectionately dubbed...