I enjoyed this book. Its great merit is that it affirms both great science and great faith. The one can, and does, benefit the other. Alexander takes us back to the idea of the scientist as one who explores the workings of God's universe. This book gets us away from the sterile either/or thinking of the evangelical atheists and the militant creationists.
The book echoes echoes thoughts from Michael Ruse (Can a Darwinian be a Christian?) who from a philosophical background shows that Christian faith and evolutionary biology are compatible, and Francis Collins (The Mind of God) who also has no problem reconciling his biological knowledge and his belief in God.
Alexander is particularly good at showing how DNA changes can generate genetic diversity which is the substrate for evolution. He also shows how natural selection is likely to be a conservative force on most occasions.
Alexander takes evolution back to its original role as a biological theory that explained the formation of new species from existing ones. As such evolution is a powerful theory, with great explanatory power. His account of species formation, and the examples provided are excellent.
Alexander is also good at showing how the idea of evolution has been exteneded to ends far beyond its biological use. The right with its belief in survival of the fittest businesses and individuals, the left with its idea of human perfectibility and inevitable historical progress, the Nazis with their idea of "lives not fit to be lived", the atheist materialist who must deny any idea of design or purpose all use evolution far beyond its intended, or valid, remit.
This book is both an excellent account of evolution, and a demonstration that science and religion can be successfully and effectively pursued together.
The two possible areas of weakness in the book are the section on the origin of life and its summary dismissal of the arguments of intelligent design.
Overall however this is a useful book, and one that allows scientists to get on with studying evolution together whatever their religious differences may be. It helps to build a very powerful bridge across the false divide presented by those who prefer to talk about, "science versus religion."