This series explores archaeological and anthropological evidence of how the earliest humans lived, from the Pliocene Epoch to the Neolithic Age. This second video looks at challenges faced by the earliest members of the genus homo, including how three fo ot tall humans killed elephants bigger than modern ones, when human culture began, why some human ancestors died out - and why homo sapiens survived. Written, produced and directed by Ned Rodgers; narrator Greg Heimer.