“As the patient searchers discern more and more about early man and his predecessors, they also may gain an ever-widening insight about modern man, his nature, his failings and his future. Most major anthropologists reject the notion popularized by Robert Ardrey (The Territorial Imperative) and others that man is inherently aggressive and that his murderous instincts derive from his apelike origins. Indeed, they have found no evidence in their digs that man was anything but a peaceable hunter-gatherer before the invention of agriculture some 10,000 years ago. It was farming, they believe, that created settlers with property to protect and fostered cultural differences that led to antagonisms between races and communities.
Richard Leakey…notes that racial differences, as they are commonly perceived, are a superficial and recent development, having arisen only about 15,000 years ago.”