This book is the latest among a long list of evolutionary texts by Dawkins. By his own admission, this book differs from his previous works. While his other books assume the truth of evolution, and thus, sought to answer specific and common criticisms against evolution (often espoused by creationists), this is the first time Dawkins has attempted to lay out the actual evidence for its acceptance by the scientific community.
His book was well written, articulated in a readable style, and quite enjoyable. In fact, I found it difficult to put the book down. Dawkins provides a good general view of why scientists accept evolution and a good case for the plausbility of natural selection as the vehicle for adaptive change. However, I do have some criticisms of his book, which prevented me from giving it 5 stars, especially if I view it from the mindset of a biblical literalist (a view I once shared many decades ago... and these are the people who need the most convincing).
My number one complaint is that he did not provide much in evidence, and where he did provide evidence it was short on detail. For instance, in Chapter 2, Dawkins mentions that all dog breeds are descended from the wolf. Similarly, broccoli, cauliflower, kale, and other commonly distinct vegetables today are all descendants of the wild cabbage. While this might seem evident to the scientifically literate, if you don't accept evolution, you might need some convincing to show that this is true. But he doesn't provide evidence or even an explanation of how we know that dogs descended from wolves or broccoli from cabbage. He merely asserts this as evidence and then moves on to chapter 3, which concerns natural selction.
In chapter 3, he discusses flowers and insects (and birds) and presents this as evidence for evolution (specifically by natural selection). But he doesn't provide much explanation of how we know this to be true. For instance, why should we conclude that this arrangement between pollen producing flower and pollinating insect to be the result of co-evolution? How do we know that the pollen producing flower was not always the way it is and that the pollinating insect was not always the way it is and that these two merely "found" or discovered one another, in essence, falling into and exploiting a niche that was always present? [This might seem crazy, but this was actually used in an argument by a creationist]
Another criticism. He was careful to define the distinction between a scientific theory and a mere hypothesis or conjecture. Yet through much of the first few chapters of his book, he is short on evidence and long on speculation. For instance, he mentions the Heika japonica crab, with the resemblance of a samurai warrior on the back of its shell. While Carl Sagan states that this was the result of natural selection, Dawkins states it probably was not; it was likely coincidence. But this very case has often been cited as evidence for evolution (by selection). Is this evidence of evolution or not? And if not, then why is Dawkins' mentioning this in his book. If anything it calls into question how we determine that something is the result of evolution (and therefore qualified as evidence), as opposed to coincidence or something else? From this example, it seems almost arbitrary.
His review of the fossil record is compelling but rehashes the same information presented in other books. And he doesn't explain how we know that the discovered fossils represent a history of the same clad, as opposed to distinct, unrelated organisms. This is particularly important since we are often comparing fossils from different time periods, from different geographical locations, and don't have access to the entire skeletal remains (let alone genetic information) of the organisms that we are claiming are descended from one another. For example, how do we know that we aren't merely pattern seeking when we look at Pakicetus, Ambulocetus, and Basilosaurus? Or Australopithecus and Homo? Moreover, he spends most of the chapter on human evolution explaining why paleontologists feud over the specific genus (or species) of particular fossils and why such arguments would be predicted under evolution precisely because they represent intermediates. But his explanation could've been condensed into 1 paragraph. It would've been far better if he spent the time to present more evidence among the mountains of evidence that are claimed to exist.
His chapter, "You did it yourself in nine months", was spent explaining by analogy that matter is capable of self assembly from the bottom-up, rather than a top-down approach as espoused by creationists. He presents his hypothesis that this is possible via "local rules" and uses the analogies of the starling and origami as examples, but this is not evidence. In fact, while analogy can clarify and improve understanding, it does not constitute evidence. Dawkins forgets that the "local rules" are functioning from a template coded in our genome. Thus, can we truly say that it is the "local rules" that create the appearance of design when a recipe is necessary for determining these "local rules"? He needs to show that the genome is capable of self assembly by local rules and that a complex organism can be created from this base. While he implies that possibility during his discussion of viruses, he does not provide much detail. Thus, the reader is left unconvinced and with more questions. Thus, if you get to this point, you will have read 50% of the book and realize that much of the book has been devoted to explanation, speculation, hypotheses, and very few presentation of actual evidence. He uses computer models to illustrate or make his points. But once again, while these models may help explain concepts, they do not constitute evidence.
The last few chapters of the book are better (beginning around page 285), but by this time he's likely to have lost most of his readers, that is, those who have not already accepted evolution prior to reading this book.
My final criticism is in regard to his reference section. Most good books concerning scientific topics contain plenty of references to primary articles. But there are very few primary articles listed in this book. In fact, you'll find more scientific literature referenced in a pop diet book than here. And I am not joking! Go to a bookstore and look at the "Notes" section of Dawkins' book yourself. He does include a bibliography, but most of the entries represent secondary or tertiary sources. This doesn't mean the information is inaccurate, but it would've been nice to have citations to primary sources for those wanting to do further research.
There are some experiments mentioned in the book (rather clever ones too), but given the fact that evolutionists are always touting the volumes of evidence (and not just from fossils) for the fact of evolution, I was disappointed to find that only a handful are mentioned in the book. As mentioned earlier, most of the book is either providing background information (about rudimentary chemistry or biology), providing explanation, or tearing down common creationist arguments or criticisms against evolution, rather than focusing on positive evidence favoring evolution. Moreover, Dawkins practically ignores the evidence from molecular biology and glosses over genetics.
In short, Dawkins writes his book as if he is talking to a fellow evolutionist (preaching to the choir). But such a person does not need convincing or evidence of evolution. You can merely point or mention the "obvious" and expect the person to understand. You don't need to go into detail or explain much. On the other hand, if you do not accept evolution or require convincing, then you will likely find that Dawkins assumes too much and does not provide sufficient data or detail as to why evolution is the best explanation for the observations under discussion.
Needless to say, I was disappointed with the book since it failed to live up to its subtitle - "The Evidence for Evolution". A more apt title would've been "The Plausbility of Evolution". He makes a good case for the reasonableness of evolution but does not provide much compelling evidence. If you are a creationist contemplating whether there is sufficient evidence for evolution, you will not be convinced by reading this book. Two far superior books (that provide better and more compelling evidence) can be found in "Why Evolution is True" and "Making of the Fittest". It isn't that Dawkins' book is bad; it provides sufficient information (on a high level) to be useful and entertaining, but don't expect it to arm you for a debate with a creationist or use it as a reference. And don't expect your creationist friend to read it and walk away a convert.