Eli Bendersky's website The fairly recent genetic explorations of Mitochondrial DNA provided a wealth of information about our past as Homo Sapiens, and about the spread of early humans around the globe, by allowing relatively clear identification of common ancestry between people.
Brian Sykes was on the fore-front of this new science and in this book he tells its story, tracing his own research of the subject. It turns out that mitochondrial DNA is quite an amazing topic, being a piece of DNA that is passed only via the maternal line, without being mixed up with the male's genes. This unique feature allows very accurate timing and identification of relations between people.
Sykes used the techniques of mitochondrial DNA to research people from all over the world, helping to solve interesting scientific debates, such as whether Asians or Americans settled Polynesia, and whether most of the modern European population descends from the native hunter gatherers of Europe or from the farmers of the near East.
The research of Sykes' group brought him to the conclusion that most (95%) of the modern European population descends from just 7 women. The book's final third tries to imagine what was life like for those "clan mothers", sprinkled with interesting insights into what archeology and anthropology have revealed about the lives of human beings during the last Ice Age.