4.0HD完美嫌疑人在线视频Part 1, "First Steps," examines the factors that caused us to split from the other great apes. The program explores the fossil of "Selam," also known as "Lucy's Child." Paleoanthropologist Zeray Alemseged spent five years carefully excavating the sandstone-embedded fossil. NOVA's cameras are there to capture the unveiling of the face, spine, and shoulder blades of this 3.3 million-year-old fossil child. And NOVA takes viewers "inside the skull" to show how our ancestors' brains had begun to change from those of the apes.