The book is trying to decipher one of the major questions faced by the paleontological scientific community today, namely the when, how and why Homo Sapiens, our species, managed to get to every last corner of the planet.
Such a vast problem requires, by default, a multidisciplinary approach, and that is exactly the author's method. He combines archaeological data, climate history studies and the latest in biological-genes research, in order to painfully and methodically reconstruct first the Exodus from Africa - birthplace of our species - and then the various phases of human diffusion. He proposes a single exodus from Africa theory, around 80.000 years ago and then follows the combined evidence (fossil record, tools, locations and genes) to trace the human voyage to Southern Asia, Australia, Northern Asia and Europe and finally the Americas.
The author makes a persuasive case and one may agree or disagree with his proposals or parts of them. Irrespective of that, one has to admire the robustly scientific approach to each and separate problem faced during this fascinating journey. Mr. Oppenheimer is the first to state the doubtful of his position in many instances and never passes mere hypotheses as facts. And, most important of all, since this is a book aimed at interested laymen, not scientists of the field, his prose is clear, as free of scientific jargon as possible and downright charming. The illustrations, maps and color plates complement the text in a most satisfying way, making for an excellent and very interesting read.