I have read many reviews that condemn Wells' book when looking for mistakes or other problems with the book, but none of the reviews mentioned any valid reasons for condemning his work. I fail to see what is so controversial in this book, aside from the fact that it supports one side only. Books often do that. If you want to read about the other side, one often has to read another book. I do this all the time. Most everyone has a position on most controversial issues, and one expects a writer to take a position when writing a book. This book tells one side which should be considered when any issue is studied. I found a few things I would quibble with, but most of the book was well documented (I looked up many of the references and found no case where the information was taken out of context or misinterpreted). One quibble I have is Wells noted several examples of putative speciation and showed they did not pan out after more research. As Wells noted, Coyne and Orr listed 25 definitions for speciation, showing it is a very problematic concept. All one has to do is find an example of a change that fits one of these definitions, such as two life forms that at one time could reproduce but in time no longer can sexually reproduce, and you have proved speciation. An example would be Great Danes and a Chihuahuas can no longer interbreed, although they were both bred from dogs that go back to the wolf. These two breeds were bred by humans and one could call them two different species, proving speciation. Of course no one does this even though this example clearly fits the common definition of speciation. Yet examples exist where claims are made that speciation occurred by selecting one of the 25 potential definitions that fits and running with it.