Exactly how modern humans evolved is a subject of intense debate. This book deals with the evolution of modern humans from an archaic ancestor and the differentiation of modern populations from each other. The first section of the book investigates whether modern populations arose from regional archaic hominid groups that were already different from each other, and argues that in fact, most lines of evidence support a single, recent origin of modern humans in Africa. Dr. Lahr then goes on to examine ways in which this diversification could have occurred, given what we know from fossils,...