Non-Fiction Reviews

Michael Behe on The Edge of Evolution

Published on November 6, 2023

Michael Behe on <em>The Edge of Evolution</em> 1

Dr. Michael J. Behe

Michael Behe is a Professor of Biological Science at Lehigh University in Pennsylvania. He argued in his 1996 book, Darwin’s Black Box that the cell structures of living organisms are “irreducibly complex” and cannot be explained by Darwin’s Theory of natural selection. This concept launched the intelligent design movement. His latest book is The Edge of Evolution: The Search for the Limits of Darwinism.

Can you summarize the thesis of your new book?: The book is called The Edge of Evolution and the gist is to find reasonable estimates for the limits of what Darwin’s theory — natural selection acting on random mutations — can actually accomplish. Clearly Darwin’s process can account for some small changes in biological systems, such as antibiotic resistance. But can it account for more complex systems, such as the intricate molecular machinery that science has discovered in the cell? Up until recently that question was impossible to answer because the molecular mutations underlying biological changes were unknown, and also because we couldn’t examine really vast numbers of organisms.; But in the past ten years all that has changed. As I detail in the book, the molecular changes underlying resistance to malaria by humans, resistance to antibiotics by the malarial parasite, and other well-studied systems show that random mutation is incoherent — that is, a series of mutations usually has little to do with each other, and doesn’t add up to a new molecular machine. What’s more, most evolutionary changes are ones which either break or degrade genes — and these are the helpful mutations! But you can’t build new molecular machinery by breaking genes. I conclude that Darwinian processes account for little of the machinery of life, and that most positive evolution must be nonrandom — guided somehow — and I argue that result fits well with the fine-tuning of the universe discovered by physics.
In Richard Dawkins’ review of your book in the New York Times, he points to the hundreds of very different dog breeds that have evolved in a relatively short period of time. And although this was done through controlled breeding, he claims that your theory would not allow for such variation in so few generations – it would be mathematically impossible. How do you respond to that?: I would suggest that Richard Dawkins re-read my book. In it I clearly state that random evolution works well up to the species level, perhaps to the genus and family level too. But at the level of vertebrate classes (birds, fish, etc), the molecular developmental programs needed would be beyond the edge of evolution. Darwinian evolution works well when a single small change in an organism’s DNA produces a notable effect. That’s what happens to give the various breeds of dogs. But when multiple, coordinated changes are needed for an effect, chance mutation loses its power.
Have you published this theory in a peer-reviewed journal? Have other scientists put forth a challenge to this quantitative argument?: No, no journal these days would touch a paper which investigates intelligent design with a ten foot pole (unless the paper aims to debunk ID). However, all the science I rely upon for my argument in the book is indeed peer-reviewed, from the best, most relevant journals. My conclusions are rather straightforward deductions from data in the literature. As you might expect for such a controversial topic, some scientists have stumbled over each other to challenge my argument. I’ve examined their writings closely and think none of them touch the heart of my argument.
Is there any way to test the concept of a designer? Is there any evidence of his or her actions interceding in the development of life on earth?: Well, it depends on what you mean by “test” and “evidence”. If you and a friend walked by Mount Rushmore, even if you had never heard of it before, you would immediately realize that the faces on the mountain were designed. Not for a moment would you think they were the result of random forces such as wind and erosion. Your conclusion of design would be certain, because you would see how well the pieces of the mountain fit the purpose of portraying an image.; Whenever we perceive a “purposeful arrangement of parts” we suspect design. The more parts there are, and the more clearly they fit the purpose, the more confident our conclusion of design becomes. In the past fifty years science has discovered a very purposeful arrangement of parts in the cell’s molecular machinery. That is the evidence for the involvement of a designer in life on earth.
Do you believe a designer only set the universe in motion, or do you think a designer intercedes occasionally?: Well, as a Christian I think God has intervened in human history. But in order to set up the general universe — including the design apparent in cells — I think God could have done that in a single instant, which unfolded over time.
Why is intelligent design science? Isn’t it just giving up on finding a scientific explanation for something that we don’t yet fully understand?: Intelligent design is science because it is based completely on physical data — the molecular machinery of cells — plus ordinary logic. Whenever we see systems in our everyday world of a certain degree and kind of complexity (like clocks), we always have found them to be designed. Now, much to our surprise, science has discovered similar systems in the cell. I see no reason to withhold the conclusion of design for cellular components. So the design of cellular machinery is an inductive argument based on physical evidence — a scientific conclusion.; When the motions of the galaxies away from the earth was first observed in the 1930s, that led to the Big Bang hypothesis. Many scientists of that time hated the idea of a beginning to nature, because it seemed to have theistic overtones. What if they had said that the Big Bang hypothesis was simply giving up on finding a scientific explanation for something that we don’t fully understand yet? If they had, physics would have missed out on a lot of progress. Science has to follow the evidence wherever it leads, or it ceases to be science. Right now the biological evidence is leading to the conclusion of design.
But that’s how they might have phrased it – “a beginning to nature” not “a designer got things started.” Do you appreciate the concern that many people have about introducing a “designer” into science textbooks?: Yes, I do appreciate people’s concerns about explicitly talking of a “designer” in textbooks. Nonetheless, science is supposed to be a no-holds-barred search for the truth. Throughout the history of science we’ve had to get used to a lot of ideas that people thought were odd. There’s no reason to shy away from the concept of a designer just because it makes some people uneasy.
Where do your Christian beliefs diverge from a literal interpretation of the Bible? I’m thinking of those areas that might conflict with our current understanding of the universe.: I’m a Roman Catholic; I never was taught a literal interpretation of the Bible. In fact, I was taught Darwin’s theory of evolution in parochial school. As far as I’m concerned, the universe and earth are as old as most physicists say they are, and life developed over immense ages. My main point of disagreement with the standard scientific story is that I think most of the development of the universe and life was set up; little was left to chance.
I’m curious if you’ve ever read mystics such as Sri Aurobindo or Ken Wilber, who take a spiritual, purposeful, but non-Christian view of evolution.: Gee, no, I haven’t. I’ll have to look them up.
Do you have any second thoughts about irreducible complexity, the theme of your first book? Do you consider this quantitative approach a better challenge to Darwinism?: I think irreducible complexity is a swell concept, which easily gets across the problem for Darwinian evolution to a general audience. It shows us quickly that Darwin’s theory is the wrong answer for much of life. However, the more quantitative approach in The Edge of Evolution actually builds on the concept of irreducible complexity, and allows us to put numbers on the likelihood of random processes building a coherent structure. It can show us that design reaches much deeper into life than we otherwise would have thought.