Evolution World Tour: The Cradle of Humankind, South Africa; The world's greatest source of hominid fossils is among dozens of caves just hours from Johannesburg

Three million years ago, an eagle soared above an enormous forest in South Africa and zeroed in on its target. Among a group of hominids searching for fruits, nuts and seeds, a 3-year-old child had strayed too far away from its mother. The eagle swooped down, grabbed the 25-pound toddler with its talons and flew off to its nest, perched above the opening to an underground cave...