This is the inside story of how one discovery - a human skull found on the island of Java - by two geologists shock the foundations of science. By uncovering new evidence they were able to date Java mans remains at 1.7 million years, which pushed back the time when humans migrated out of Africa.
Carl C. Swisher III is an associate professor in the Department of Geological Sciences at Rutgers University.
Garniss H. Curtis, a pioneer of modern techniques for dating ancient rocks, is Chairman of the Board of Directors of the Berkeley Geochronology Center.
Roger Lewin is the author of seventeen books, including
Bones of Contention and
Complexity: Life at the Edge of Chaos, both available from the University of Chicago Press.