It seems you're asking about the process of evolution as described in a book. However, you haven't specified which book you're referring to.

To answer your question accurately, please tell me the title and author of the book you're interested in.

Here are some possibilities:

* Charles Darwin's "On the Origin of Species": This classic book details the theory of evolution by natural selection.

* "The Greatest Show on Earth: The Evidence for Evolution" by Richard Dawkins: This book provides a modern perspective on evolution, emphasizing the overwhelming scientific evidence for it.

* "Evolution: The Human Story" by Alice Roberts: This book explores human evolution from a historical and scientific perspective.

Once you tell me which book you're referring to, I can provide a specific answer about the evolutionary process it describes.