Let me begin by saying that I am not a biologist. I have not studied biology beyond Biology 100 level at university, and I remember little enough of what I did that year. I never read a book about evolution until I was 60 years old, and the first book I read was Darwin’s Origin of Species. I understand that many biologists have never read Darwin’s book. That is a scandal, because it is not only a work of science, it is a work of literature, and a part of the history of their discipline that biologists should honour. However, my intention is not to scold biologists for not reading one of the seminal texts of their own discipline, but to express my own feeling of the oddness of having people argue against evolution, and I realise how much more strange it must seem to those who have made a minute study of evolutionary biology. Yet when people argue — as a number of commenters have recently done — against evolution, as though evolution were still something in dispute, I have an overpowering sense of the weirdness of what is being attempted. It is as if someone were to argue that the earth is flat, or that the sun goes round the earth every twenty-four hours, or that Newtonian mechanics were simply based on scientists’ presuppositions, and had no basis in the way that objects behaved in relation to each other.
And then I think of the biologists, like Dawkins and Coyne, who are trying desperately to convince people that if they will only pay attention, and learn a few basic things about the way living things have developed — and we have all seen the evidence in the museums, or in books about dinosaurs — they would acknowledge that Darwin was right, and would themselves reach the point where they would find it strange that anyone should doubt that evolution had taken place, or should try to argue against it, as though it is something that could be dispensed with by a few logical arguments thought up in an afternoon. I remember the time when Richard Dawkins was speaking, with infinite patience, with a woman who kept telling him that if only he could produce some evidence, then perhaps it would be reasonable to believe in evolution; but that, failing that, there was no reason to believe that the living things we know came about by means other than direct creation by God. I wondered, as I watched the interview (which seemed to go on for hours), how Dawkins could keep his cool in the face of stupidity so stupendous! And then I think how difficult it must be to be faced with this kind of blind refusal to look at the facts, how peculiarly strange (almost uncannily weird) it must be to know so much, and yet to have someone simply reject it as though it were simply empty myth and fable. Here is just a little taste (an edited clip) of that interview with Wendy Wright (former president and CEO of Concerned Women for America, a conservative Christian political action group active in the United States) – and the whole thing goes on for at least an hour in the same vein:
I’ll wager that, if you did make it to the end of that clip, you did it while gritting your teeth! (I hope you approve my cutting off Wendy Wright in mid-sentence!) That is just so amazingly frustrating to watch, and over the last few days I have been experiencing the same vague sense of unreality. How could something which lies at the very heart of modern biology — without which modern biology could not be understood at all – be doubted by so many? Yet some commenters on choiceindying.com have recently expressed these doubts, as though they made sense, and I have an extremely odd –almost ”creepy” – feeling as a result — a bit like Alice’s experience of passing through the looking-glass.
Take Bob Wheeler, for example. Recently, Bob argued like this:
The appearance of design is evidence of design, and Darwin’s attempt to explain it away through natural selection is unconvincing. We add to this eyewitness accounts of miracles, most notably that of the resurrection of Jesus from the dead, contained in the gospels, as historical evidence of the supernatural.
The first sentence of this quote is the business end of this comment, at least so far as evolution is concerned; the rest presumably gives the reason for rejecting Darwin’s explanation. Of course, what he says is false, because, since Darwin, the appearance of design is definitely not evidence of design. And not only did Darwin make an attempt to explain the claim away; he demonstrated that appearance of design is not evidence of design. Bob goes on to say that he has read and even reviewed Jerry Coyne’s book, but remains convinced that the Bible is right, after all. But if he read Jerry’s book, then he knows that this is not just an explaining away of something; it is a matter of providing evidence of that very thing. What is odd is that Bob seems to find the supposedly eye-witness accounts in the gospels to be a sufficient basis for believing in the supernatural, but is unwilling to accept massive scientific evidence as even the slightest bit compelling.
Now, it is true, Bob has a blog, and he has, indeed, “reviewed” Dr. Coyne’s book, in a total of 769 words! The review consists, in the first place, of an argument designed to show that Coyne’s method of argumentation is fallacious, because it involves, Bob says,
building a case on circumstantial evidence, an argument marked by circular reasoning and logical non sequiturs. There are two major weaknesses in this kind of argument. First of all, what if the evidence does not fit perfectly, if there is something that the theory cannot explain? And secondly, What if we cannot establish a direct causal link, the proverbial “smoking gun”? In this case the question is whether or not it is even possible for evolution to take place at all.
Now, notice, “what ifs” do not refer to any of the ”arguments” or the evidence presented in Why Evolution is True. It merely states that the arguments are fallacious and then adds a question: What if? When someone is so careful to steer clear of the actual text which he claims to be reviewing, it is clear that he has either not read it closely, has not found anything to which his strictures apply, or is merely blowing off steam. He certainly has not shown that Why Evolution is True has failed to produce evidence for its claims. Indeed, it does, and this part of the Bob’s argument is therefore empty.
What about the next part? First, he turns to the fossil record. He points out that the fossil record is not continuous, and shows discontinuities, and then he says:
He [Dr. Coyne] is honest enough to make this intriguing statement: “When you look at animals and plants, each individual almost always falls into one of many discrete groups” (p. 169). That is the indisputable fact. But which theory does it support, evolution or creation? We think the latter.
Now, I’m sorry, but this is simply dishonest. When Jerry speaks of “discontinuities of nature,” he is referring, not to the fossil record, but to the world as we know it. We don’t see, for example, cats blurring “insensibly into one another through a series of feline intermediates.” (169) What we see are clusters of organisms that we call species. How did these clusters get to be that way? He acknowledges that this might seem to be a problem for evolutionary theory, so he goes into a great amount of detail in order to explain what biologists mean by the word ‘species’, and why it is so difficult to define the term.
Many people, by the way, argue that Darwin nowhere shows in the Origin of Species how species evolved. But of course this is wrong, for the truth is that species are not distinct natural kinds in quite the way that belief in creation suggests. For the creationist there are hard and fast distinctions between species, each one created after its kind, as the Bible says. But species are not fixed and stable in this way, and they shade off by slow degrees into successive species in a diversity of ways, depending on environment, geological or meteorological hazards like earthquakes, the formation of mountains, the narrowing of seas, the widening of oceans, storms — even meteorites and other space debris – indeed, anything that affects the environment, isolates or brings organisms together, causes extinctions, and so on. Indeed, as Dawkins points out, if we were to trace our own lineage back through 185,000,000 generations we would come to our great-great-great ….. repeat until 185 millionth-1-grandmother or grandfather fish!
And this is where Bob’s “review” is misleading, because it suggests that none of this is explained. But Coyne makes it very clear that there are different concepts of species, precisely because of the fact that we do not have things created after their kind, in the way that the Bible prescribes. For example, paleontologists, when they are classifying fossils, don’t have functioning organisms to work with, so they have to make do with an appearance-based concept of species. But working biologists use the notion of the species as a reproductive community (the BSC or biological species concept). A species in this sense (though it does not fit organisms that do not reproduce sexually — another complication) is a community of interbreeding organisms that is reproductively isolated from other such groups (see 172).
And this leads us on to the point that Bob seems to have missed. How could such groups, if they are interbreeding, ever evolve into completely different organisms? This is what Bob calls “macroevolution”, and he says that it is impossible. But he misses the vital words “reproductively isolated.” Take a species defined in terms of the BSC as defined above. Suppose that, for some reason, part of the species community is isolated from another part, and begins to evolve (“microevolution,” Bob calls it), but this time, independently of the larger group from which it has been isolated — perhaps it floated on tree waste down a river and onto an island many miles from its place of origin. So it evolves (microevolves) for many many generations, and perhaps hundreds or thousands or even millions of years later suppose that the product of this evolution is reunited with the source community (let us call it), which has also been evolving during this time independently of this orphaned group. Depending on the track that these independent evolutionary paths have followed, the result could be capable or incapable of mating with members of the source community. It may be as different as a fish is to a human being (as we saw above). If they are incapable of interbreeding, then a new species has developed which will henceforth evolve independently of the members of the source community. The result, in case you wondered, is “macroevolution,” the evolution of a new species.
But Bob didn’t tell us the whole story, so it is made to seem as though Coyne didn’t provide either the argument or the evidence. But Bob’s claim is vacuous. Indeed, there is a wonderful example of reproductive isolation in what are called “ring species”, species that are geographically spread out so that while species at the geographical extremes cannot interbreed, neighbouring species can. Larus gulls in northern temperate latitudes are a good example, and you can read about them here (which also introduces new complications based on new studies). This link will take you to an article (pdf) entitled “Ring Species as bridges between microevolution and speciation,” in case you wondered what this had to do with Bob’s claim. But the point has been made again and again in the study of the fossil record, which is corroborated by the evidence of DNA sequencing. There are not only discontinuities of nature in terms of existing species, but there is also overwhelming evidence for evolution of species over almost unimaginably long periods of time. The claim, made by creationists, that there is no evidence, is an empty one. As Dawkins told Wendy Wright, look and see (and those of you who know your gospels will be able to spot a biblical reference in those words).