Donald Johanson is known worldwide for his discovery of the Lucy skeleton. He conducts frequent lectures, has written five books and is founder and president of the Institute of Human Origins in Berkeley, California. Blake Edgar combines backgrounds in anthropology, zoology and journalism to report on a broad range of scientific subjects. David Brill has been staff photographer for National Geographic, and has worked extensively with Donald Johanson on field research sites for the past twenty five years. The authors live California, USA.