Usually authors will start out their writing careers making a general case on behalf of something, and then later deal with the specific objections as they arise. But not Richard Dawkins. As the leading prolific evolutionary author in our generation he finally got around to writing the book that many authors would've written first, this one. Since up until now he has not set forth the evidence for evolution as a whole, he calls this book "my missing link" in his chain of books, and it's long overdue.
Taking the title from the Ringling Bros. and Barnum & Bailey Circus, Dawkins begins by asking us to imagine what it would be like to be a European history teacher who is "continually faced with belligerent demands to give equal time" in his classes to Holocaust deniers. To him that would be what it's like to teach the scientific fact of evolution around the world, especially in America, where 40% of us deny that humans evolved from other animals and who claim instead we were all created as distinct species not more than 10,000 years ago. Just like the Holocaust deniers these people are "history-deniers" too. The antidote to that kind of ignorant thinking is this present work, which presents "the positive evidence that evolution is a fact" (p.6). Many bishops and theologians embrace evolution as a fact, even if some of them accept it begrudgingly.
Who is he trying to reach? The creationist "history-deniers" themselves, but more importantly those who find themselves inadequately prepared to argue the case for evolution (p. 8).
He claims: "Evolution is a fact. Beyond reasonable doubt, beyond serious doubt, beyond sane, informed, intelligent doubt, beyond doubt evolution is a fact. The evidence for evolution is at least as strong as the evidence for the Holocaust, even allowing for eyewitnesses to the Holocaust. It is the plain truth that we are cousins of chimpanzees, somewhat more distant cousins of monkeys, more distant cousins still of aardvarks and manatees, yet more distant cousins of bananas and turnips...continue the list as long as desired...It didn't have to be true, but it is. We know this because a rising flood of evidence supports it. Evolution is a fact, and this book will demonstrate it. No reputable scientist disputes it, and no unbiased reader will close the book doubting it." (pp. 8-9).
These are very large claims he's making. Are they justified? Yes, I think so. I challenge the creationists to place this comprehensively argued book, which is illustrated by many diagrams and glossy full colored pictures, next to what a few ancient superstitious people wrote in the Bible and see which one makes the most sense. My bet is that if believers are truly interested in the facts they will see evolution is indeed a fact.
Dawkins knows how to communicate, he knows where to begin his case with dog breeding, and he knows science. It's practically all here within the pages of this book. The reason why we don't see evolutionary change is because it takes place slowly over generations, but dog breeders can do it quickly and efficiently. "Every breed of dog," Dawkins writes, "from dachshund to Dalmatian, from boxer to borzoi, from poodle to Pekinese, from Great Dane to Chihuahua, has been caved, chiseled, kneaded, moulded, not literally as flesh and bone but in its gene pool....The relevance to natural evolution is that, although the selecting agent is man and not nature, the process is otherwise the same." (p. 34).
With regard to flowers, birds and insects make these changes rather than humans, naturally, not artificially, just like the wind did before them: "Hummingbird eyes, hawk-moth eyes, butterfly eyes, hoverfly eyes, bee eyes are critically cast over wild flowers, generation after generation, shaping them, colouring them, swelling them, patterning and stippling them, in almost exactly the same way as human eyes later did with our garden varieties; and with dogs, cows, cabbages and corn." (p. 52). And he asks us: "If so much evolutionary change can be achieved in just a few centuries or even decades, just think what might be achieved in ten or a hundred million years?" (p. 37).
To believers who object that the earth isn't old enough Dawkins marshals overwhelming evidence that it is billions of years old, along with evidence piled upon still more evidence to show evolutionary development of life on earth is indeed the greatest show on earth, and he is clearly in awe of it.
There are a few great books on evolution but this is a superior book long overdue by today's leading communicator of science. You should get it and think through it, especially if you're a "history-denier." Face the evidence and then change your beliefs. It's the intellectually honest thing to do. Then you too will thank Dawkins like so many of us have for his writing in these areas.