This book examines the relationship of the peoples of the planet, both in terms of genetics, and in terms of languages, and finds the two family trees thus exposed agree to a remarkable extent. This information is used to give a chronology to the "Out of Africa" expansions to cover the world. The genetic data is also used to argue against racism, since the very concept of "race" is ill-defined, as there is nearly as much internal genetic variation within any given group as there is between groups.
The translation is slightly clunky in places, but mostly reads well. It has a rather episodic structure, with little final conclusion. The rant against racism is certainly worthwhile, and the weaving together of various bits of data is interesting, but I feel it is trying to work up to some grand synthesis, which is unfortunately missing. This might be because it is put together from (revisions of) a series of lectures given in the 1980s. So, interesting, but it could have been more.