Ancestors In Search of Human Origins Author:Donald Johanson, Lenora Johanson, Blake Edgar With revolutionary scientific theories, dramatic photographs, and his own exciting discoveries, world-famous paleoanthropologist Donald Johanson supports controversial hypotheses that challenge our most fundamental theories of human ancestry: — Our earliest ancestors left the trees to walk on two legs at least four million years ago as part of a ... more »unique sexual strategy. Our first large-brained ancestors survived as scavengers, competing with lions and hyenas for food, rather thatn being the noble hunters of popular imagination. Neandertals are a specialized, extinct side branch of the human family tree and were never part of our own species. Modern humans first evolved in Africa and later migrated around the world. « less