A Mousetrap for Darwin
By Amy Beange
Richard Dawkins, author of The God Delusion, insists that Darwin’s work made it possible to be an intellectually fulfilled atheist. Prior to Darwin, the question of origins was answered with reference to the creative acts of Almighty God. Design and laws required a Designer and Lawgiver and those who rejected the existence of God were left without a satisfying answer as to how we all got here. But Darwin’s proposal of natural selection as the mechanism responsible for the complexity of life appeared to make God superfluous, and atheism as a system of thought finally had its own explanation for existence.
Darwin’s theory was greeted with a good deal of controversy, precisely because it seemed to show that the various species of animals and plants, which were believed to be the result of God’s special work of creation, were nothing more than the results of natural law. Previously the existence of God was taken as a given, for how else could we explain how we all got here? “The things that are made” were the clearest testimony of God’s “eternal power and Godhead” (Rom. 1:20). The believer did not have to argue the point but could focus on God’s special revelation, the message of the scriptures, which told us of salvation through Christ.
Darwin’s theory changed all that. In addition to explaining the differing beaks of the various Galapagos finches, evolution’s explanatory powers have been expanded over time to cover, not just the small differences within species, but the larger differences that separate species, genera, and families—all the way back to the original simple cell from which it is supposed that life descended. If life can be explained without reference to God, the believer is in a tricky position. The gospel presupposes that we are accountable to God because he is our creator. But a non-existent creator is of no concern to anyone, thus making the gospel unnecessary.
“The gospel presupposes that we are accountable to God because he is our creator. But a non-existent creator is of no concern to anyone, thus making the gospel unnecessary.”
But a question remains. After a century and a half, does Darwin’s theory hold up? In my humble opinion, not really. In Darwin’s day, the cell was thought to be quite simple, a bag of undifferentiated jelly. Today we know even the simplest cell is fantastically complex. Can such a thing arise through the long undirected process of natural selection and mutation? Is there a clear line of structures of ever-increasing complexity that can account for what we observe today?
Biochemist Michael Behe argued otherwise in his 1996 book Darwin’s Black Box, in which he claimed that the cell was a “black box” that Darwin simply could not understand given the lack of knowledge in the 19th century. Today we know that for one type of organism to change into another type, we must have an explanation on a biochemical level, and it turns out that with 21st-century knowledge we understand that the required changes are much more involved than Darwin could have dreamed. Behe argues that the tiny machines that govern our bodies are “irreducibly complex,” i.e., they are constructed in such a way that to function properly they must have a minimum number of parts working in harmony, without which they cannot function. Such complexity cannot be achieved through incremental steps since these machines, minus a part or with a modified part, do not become less functional, but stop working altogether.
Behe’s book inaugurated what has come to be known as the theory of Intelligent Design (ID), which, in addition to highlighting the irreducible complexity found in biological machinery, posits that the complex information found in the DNA of each living cell is evidence of design, and necessarily a product of intelligence, not unguided natural forces. If when walking through the woods you come upon a structure with four walls, a roof, a door, and windows, you do not marvel at the wonderful coincidence in which trees fell on top of each other to produce such a thing. Rather you recognize the work of intelligent humans who conceived and crafted a little cottage. Just as we can recognize design in non-living structures, so we can recognize design in living structures since organisms are comprised of machines far more complex than the ones we create.
It has been 25 years since “Darwin’s Black Box” was published. As a follow-up Behe has come out with A Mousetrap for Darwin (2020), a collection of his works in which he addresses the many criticisms of his ideas, showing that, rather than ID being flattened under a weight of evidence favouring Darwinian evolution (DE), it is DE that is rapidly losing its explanatory power.
To illustrate his contention, Behe puts forward the mousetrap—a simple structure of five pieces (a wooden base, a spring, a hammer, a rod, and a trigger)—which cannot function if even one piece is missing. Since Darwinian evolution argues that complex structures can emerge via a series of small changes to simple structures, Behe asks the question, what could be a form of mousetrap, simpler than the one he describes, that could be adapted into becoming his version via small changes? His answer is that there are none and thus DE is an insufficient explanation for the origin of the mousetrap.
Behe’s critics have proposed simpler mousetraps, but the point was not to come up with simpler options, any more than pointing to simple eyes in the animal kingdom are evidence that our eyes evolved. Rather, the point was to propose a series of traps in which a simple version could steadily improve by slight modifications until it finally becomes the trap that Behe proposed as irreducibly complex. The proposed solutions by Behe’s critic did no such thing. The changes necessary to get from one stage to the next proved to be more involved than described in the critique.
The first trap with a single spring morphed into the second trap in which the spring was configured differently, and a wooden base was added. That is a nice conceptual idea, but in the real world quite a lot needs to happen to get from one to the other and each change must confer an improvement upon the trap as a whole. For instance, what is the advantage to the original trap with the addition of a wooden base if the spring is not affixed to the base? The base needs to be added, the spring needs to be stapled to the base, AND the spring needs to be shaped differently. That is not a singular change – multiple changes need to occur simultaneously if the new trap is to be of any use. If three changes are required to improve functionality, and only two of the changes occur, you don’t end up with a trap that is two-thirds as effective as the original trap, you end up with a trap that is useless.
If proposing a series of mousetraps that outline a path of development has proved impossible, then DE clearly has its work cut out when proposing developmental paths for living organisms. Behe’s prime example of an irreducibly complex biological machine is the flagellum of a bacteria, essentially an electric motor more advanced than anything humans can do. He notes that if DE is to be demonstrated, then “bacteria are a good choice because they can be grown in huge numbers with short generation times—just what Darwinian evolution needs.” If DE should be observed happening anywhere if should be within the several decades of experimentation on such prolific organisms. Yet twenty-five years of observation has yielded no evidence that natural selection is capable of making the changes necessary for the creation of new systems. It is perfectly capable of making small changes to existing systems but appears unable to coordinate those changes to the degree necessary to create more complex systems.
“If when walking through the woods you come upon a structure with four walls, a roof, a door, and windows, you do not marvel at the wonderful coincidence in which trees fell on top of each other to produce such a thing. ”
The blood clotting system found in most animals is another irreducibly complex mechanism that Behe details in Darwin’s Black Box. Blood clotting expert Russell Doolittle criticized Behe, citing experiments with mice in which one line of mice had one component from the system removed and another line of mice had a different component from the system removed. When the two lines were crossed the resulting mice were normal, Doolittle reported, proving that the system was not irreducibly complex and could function just fine with fewer parts.
In reply Behe pointed out that while the mice lacking both parts did not suffer some of the problems that plagued the mice lacking just one part, the mice lacking both were still severely compromised, since in the end, the missing parts meant they no longer had a functioning blood clotting system at all—decidedly not an improvement in fitness but a drastic reduction of it. Doolittle’s argument amounted to saying that a man with both legs missing is better off since he is no longer threatened by varicose veins. But Darwinian evolution is proposed as the means of increasing fitness rather than decreasing it, thus the work Doolittle refers to is going in the wrong direction.
Darwin himself said “If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down. But I can find no such case.” However, the flagellum and the blood clotting system seem to be just the kinds of things that make Darwin’s theory vulnerable. Darwin himself addressed this issue, taking the human eye as an example. He pointed to animals of his day that had simpler organs for seeing than that of humans and suggested that such organs might have served as intermediate stages.
Darwin’s explanation convinced many but Behe makes a salient point about the weaknesses of such scenarios; they tend to gloss over the difficulties in getting from one state of being to another. Biological organisms are highly complex at the molecular level, as Behe makes clear: “If two proteins don’t bind each other in the correct orientation…if they aren’t placed in the right positions, if their new activity isn’t regulated correctly, if many details aren’t exactly correct, then the putative Darwinian pathway is blocked.” It is one thing to say that a simple eye can be improved with the addition of a gelatinous material that functions as a lens, but it is quite another to describe how such an addition could happen via incremental steps. How much material is needed? How is it placed? How is it held in place? How does the brain read the information from this new lens? All these changes must be put in place simultaneously for the “gelatinous material” to function as a lens. Improperly placed material or material that slides around, or a lack of ability to read the added information doesn’t mean a slightly improved seeing apparatus, it means one that is worse off.
Darwin had no way of knowing any of this in his day—molecular knowledge was quite out of reach for anyone in the 19th century. But “Darwin’s simple steps are now revealed to be huge leaps between carefully tailored machines.” What such machine can be created via small modifications?
Behe asserts in Darwin’s Black Box that such things have never been explained in detail in Darwinian terms and in Mousetrap he notes some scientists who uphold DE also admit he is right: Microbiologist James Shapiro has written, “There are no detailed Darwinian accounts for the evolution of any fundamental biochemical or cellular system, only a variety of wishful speculations.” (National Review, 1996). And according to Evolutionary biologist Andrew Pomiankowski, “Pick up any biochemistry textbook and you will find perhaps two or three references to evolution. Turn to one of these and you will be lucky to find anything better than ‘evolution selects the fittest molecules for their biological function’” (New Scientist, 1996).
Has the situation improved any since Behe’s original critique? Well, consider how he open’s Mousetrap: “Since the turn of the millennium a raft of distinguished biologists have written books critically evaluating evolutionary theory. None of them think that Darwin’s mechanism is the main driver of life.” He backs up his assertion with a list of fourteen books in the notes, published by premier universities such as Oxford, MIT, and Cambridge.
And yet, DE reigns supreme in the popular imagination and in mainstream media, and the barest hint of “intelligence” or “design” in one’s explanations is enough to arouse derision. This, in spite of the fact, Behe argues, that design is something we are all familiar with and can detect with ease. He notes that if evolution via natural selection is true then it means nature behaved in the past in ways we never see it behaving now; that the complex systems we now see arising only from already existing complex systems must by some entirely unknown means have in the past arisen from simple systems via incremental changes. He further asserts that viewing Darwinian evolution as the only viable explanation is an unnecessary limitation placed on the scientific enterprise, leading to much wasted time and energy going down what can clearly be seen by now as a dead end.
What could possibly by the cause of such prejudice toward the idea of intelligent design, even if some forms of it are similar to Darwinism? Behe notes that, as an explanation, ID points to something outside the natural world, which naturally puts people in mind of God, which has “philosophical and theological implications that people find uncomfortable.”
“twenty-five years of observation has yielded no evidence that natural selection is capable of making the changes necessary for the creation of new systems.”
What sort of implications? Well, if the designer transcends nature, he/it transcends us. Since he designed the universe and all that is in it for a purpose, it is reasonable to assume he has a purpose for human life, a purpose that might involve how we behave and how we relate to him. And that leads to the uncomfortable conclusion that we are not in fact the measure of all things. Instead, God is the measure of all things, and the thought that he might have something to say or even to do about the choices we make during our short lives is simply unacceptable.
Moreover, any hint of a suggestion that “God could have used evolution” is enough to taint the enterprise, for Darwin’s innovation was not intended to suggest a natural means by which God might have created, or to suggest God used evolution to continue attaching purpose to cosmology. Instead, Darwin’s whole point was to posit a purely natural means of creation, quite apart from any purpose. He sought a purely natural way to explain what previously had relied on intelligence and will, whether of God as separate from creation or of an ensouled creation itself. It is understandable why humans might wish to come up with explanations for the world that prove God is unnecessary, since that would alleviate our sense of accountability to the higher standard to which we are inexorably held.
Intelligent design, which strongly points to God, has significant implications. But Behe argues that all explanations for the origin of life have such implications. Referencing the aforementioned Dawkins quote, “Darwinian evolution made it possible to be an intellectually fulfilled atheist,” Behe points out that prior to Darwin the atheist had no reasonable explanation for existence. How things came into existence was a mystery that had no explanation, and such a state of affairs was not intellectually satisfying. It was too much akin to saying, “I don’t know how things appeared, they just did.”
After Darwin, the atheist could confidently assert that natural laws, plus time and chance, all worked together to produce the complexity of existence. And when it came to the question of God the Darwinist could say, “I have no need of that hypothesis.” Belief in God could be shuffled to the side in scientific discussions, a quaint artifact of pre-modern times invoked to give some sort of meaning to suffering but certainly not necessary for the real matters regarding the nuts and bolts of life on earth.
But if we have learned anything in the last 150 years it is that life is more complex than we can conceive. Whenever we develop technology that lets us look more closely at the natural world, we are stunned to find whole new worlds. It can feel as if the inside is bigger than the outside. Marvel fans got a taste of this in the movie “Endgame” where Ant-Man travels to the quantum realm where dust particles take on the relative size of universes. The guided arrangement of these infinitesimally small particles make life possible in our everyday world. Yet we scarcely recognize that the visible realm is governed by innumerable machines working in concert, sight unseen.
Strangely enough, scientists seem to have no trouble identifying intelligent design when looking beyond our world. The SETI program (Search for Extra-Terrestrial Life) searches for signs of intelligence coming from outer space, and every scientist and technician involved knows what to look for, knows the difference between natural phenomena and phenomena that could only have arisen from intelligence, i.e., complex, coded information. If we can detect intelligence when we look to the stars, why not when we look into the cells of living beings?
Perhaps it is not the scientific aspect of the issue that pushes people to deny God’s existence. As Behe notes, every explanation of origins carries philosophical implications, and someone who is unmoved by data that appears to require an intelligent origin may have other reasons for doing so that we might want to explore. We might ask our friends or colleagues what sort of evidence they would accept as pointing to the existence of God? Or we might ask if evidence were produced for them that (hypothetically) forced them to concede God existed, would they be at all interested in learning about him? Their answers might help us to understand how to proceed.