(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here.)

In the previous post about Dawkins’s book, I talked about almost all the kinds of evidence that Dawkins presents for evolution, except for the fossils.

But what about fossils? He talks about that evidence too but repeatedly points out that the case for evolution would be iron-clad even if there were no fossils at all. The fact that fossil evidence exists, and keeps accumulating thick and fast in recent years, is simply a bonus. Remember that when Charles Darwin developed his theory, there was hardly any fossil evidence to speak of, except for those that had been sufficient to persuade the geologist Charles Lyell (1797-1875) to conclude that the Earth was at least hundreds of millions of years old, much older than the 6,000 years or so that was currently believed, even though he himself at that stage believed in special creation and thought that species remained unchanged.

So why do creationists keep focusing on the fossil record and keep saying things like “Where are the transitional fossils?” or more crudely “What about the missing links?” Some of them (yes, I am looking at you, Crocoduck) are either woefully ignorant of what the phrase ‘transitional fossil’ means or are taking advantage of the ignorance of their audience. Others who are a little more sophisticated do this because they know that the conditions for successful fossilization rarely occur, and since we are talking of a fossil record over hundreds of millions of years, there are bound to be periods for which we have no fossils along any branch of the evolutionary tree. But we keep finding new fossils and the intervals over which there are no fossils keep getting smaller.

Some evolution deniers exploit a feature of the Linnaean classification system of biology that divides living things into discrete categories and requires one to place a newly discovered fossil into a specific category. But evolution is a smoothly transitioning system and it is inevitable that some decisions as to where to place an item are going to be arbitrary. As Dawkins says, it is like the definition of an adult. The law might classify you as an adult on your eighteenth birthday but were you significantly different the day before? As one moves from (say) fifteen to twenty one, one makes the transition to adulthood but one cannot pinpoint exactly when it occurs. There are some people younger than eighteen who are very mature and there are people over that age who are quite immature. But the system requires us to fix who is an adult and who is not and put each person into one or other category. So people who really are in a transitional stage will be classified as either adult or non-adult, and the system of classification by itself eliminates any identification of transitional stages.

The classification system of biology similarly eliminates the labeling of transitional forms. One sign that a fossil is an intermediate between two species is when paleontologists strongly argue about the category in which it should be placed. But once that argument ends, and the fossil placed in one or other category, it does not mean it is no longer transitional. It simply means that it has been pigeonholed for convenience.

Dawkins points out that further evidence for evolution comes from the relatedness of the body patterns of living things that indicate that we had common ancestors. The closer the details of the plans, the more recent the common ancestor.

Furthermore, the way that our bodies are presently constructed reveals our evolutionary history. There are so many aspects of our bodies that are inefficient or wasteful and cannot be made sense of in terms of good design. But they can be understood when we look at the body plans of our primitive ancestors and see how the inefficient aspects of current species were the result of slow adaptations to changes in other parts of our bodies.

He provides a good analogy to illustrate the difference between how a god-like designer and natural selection work. An aircraft engineer (representing a god-like designer) can ignore much of what came before and design a jet engine from scratch using the principles of aerodynamics, and optimize its workings using current technology. But what if the designer were constrained (like natural selection is) to start with a propeller engine and had to make changes using only what was readily available at hand and each change had to be tiny and also provide at least a slight improvement in performance? He would still end up with a better aircraft engine but it would a patchwork mess, nowhere close to the sleek modern jet. Our body plans reveal the patchwork model of natural selection and not the planning of a god-like designer.

Will Dawkins persuade more people to realize that evolution by natural selection is the way to go and that the god hypothesis is unnecessary? Yes, but it will not be easy and not many will change their views directly. As Hugh Laurie says in one episode of House: “Rational arguments don’t usually work on religious people. Otherwise there would be no religious people.” That might be an overly pessimistic view of the power of reason but I think it is largely true. But the secondary effect of the book, enabling many more people to make the arguments that only a few specialists like Dawkins makes, is what is important.

This is why we need to speak out for science and against religion and show that religious beliefs are in opposition to rational thought. We need to allow people’s inner rationality, which we all possess and use in almost all aspects of our lives, to break free of the smothering effects of religion. Once people realize the need to apply rational thought to even their religious beliefs, then there is hope.

POST SCRIPT: Media coverage of atheism

NPR has a report on the new atheists and the accommodationists.

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here.)

I just finished the latest book by Richard Dawkins where he makes the case for evolution. One might think that this is what almost all his other evolution books have been about too but as he says in the introduction, in his previous books he was tacitly assuming that people accepted the basic idea of evolution. He was just explaining in more detail how it worked.

His goal in the current book is to persuade the reader that evolution is an undeniable fact by marshalling all the evidence and logic that has persuaded almost all scientists that it is true. Will he persuade those who disbelieve in evolution? That is unlikely to occur directly because the real disbelievers in evolution are too locked in their religious worldview to even read a book by a noted atheist. Even the few religious apologists and theologians who will read the book in order to try and counter its arguments are unlikely to change their views because their denial of evolution and the theory of natural selection has no rational basis. As Jonathan Swift said, “You cannot reason a person out of a position he did not reason himself into in the first place.”

But Swift may have been too gloomy in his assessment. If what he said were strictly true, then there would be hardly any atheists at all since almost all of us were likely raised in religious households and simply accepted religious beliefs the way we accepted Santa Claus and other fairy tales told to us by the adults in our lives. And yet unbelievers are a rapidly growing group. But in Swift’s time (1667-1745), the arguments against god and religion were not nearly as strong as they are now and there were not nearly as many open atheists actively promoting disbelief, due to various blasphemy laws that protected religion from the arguments of apostates. We are truly living in a much more hopeful time.

The religious readers who may be persuaded by Dawkins’s book are those who already realize that creationism is a weak explanation of life and are looking for something better. Others who may be persuaded are those religious people who have had some kind of epiphany that has made them realize that the god hypothesis is implausible and are now looking for a satisfactory worldview that can replace their former belief structure.

But the people for whom TGSOE will prove to be most valuable are readers like me, who are not specialists in evolutionary biology but have heard and read enough to realize that it is a powerful theory and that intelligent design and other forms of creationism are laughably inadequate as competing explanations of the diversity of species. What this book does is provide us with a one-stop shop, where the evidence is presented in a clear and concise way, that we can use to persuade those whom we know and who are open to persuasion.

In his book, Dawkins convincingly makes the case for two things: that evolution has occurred and that natural selection is (largely) how it occurred.

He points out how we know so much about evolution from artificial selection, from the experiences of breeders to produce new species and from the way that species like dogs and cabbages have evolved before our very eyes. Even the banana, which in its current form is seen by some as the ‘atheists nightmare’ because it seems to be so perfectly suited to human eating, was initially a highly unappealing and unpalatable food, coming into its present form only as a result of careful breeding.

He then talks about how in the wild, symbiotic relationships that occur between insects and plants or between predator and prey or as a result of competition for sexual favors or the sudden isolation of a species all can drive evolution quite dramatically, sometimes visible in our lifetimes, although most of the time it is very slow. These natural processes play the role that breeders play in artificial selection.

He points out that although evolution in the wild is usually glacially slow, we have many independent ways of judging time over geological scales, using sedimentation rates in geology, radiometry, the magnetic field switches that are recorded in the shifting continental plates, the rate of DNA mutations, and so on.

Furthermore, the way species are distributed across the globe is powerful evidence for evolution and against special creation. Why are the marsupials concentrated in Australia? Why is it that we find different species in different parts of the world? How come Madagascar and the Galapagos have so many species found nowhere else? This particular feature that Darwin noted in his around the world trip on the Beagle was what initially caused Darwin to question special creation by god and to realize that something else must be going on.

It is interesting that in Darwin’s time the idea of continents moving was not even considered. And yet as that theory became accepted and the idea that initially there was a single land mass called Gondwanaland that became broke into bits and separated added to the explanatory power of evolution because it explained how species spread all over the globe.

And then there is the very recent and powerful DNA evidence, which really seals the case that we are all descended from a common ancestor, the original self-replicating molecule, probably a primitive form of RNA, that became DNA and slowly evolved as a result of errors during the replicating process, leading to the diverse species we see.

What is most impressive is that all these diverse pieces of evidence and argument tend to converge in their results. It is this convergence that provides the power of the argument for evolution.

Next: What about fossils?

POST SCRIPT: Richard Dawkins on superstition and spirituality

It is amazing how people take seriously stuff that they have just made up.