The Edge of Evolution

The concept of intelligent design has undeniable appeal. Forming a kind of middle ground between creationism and evolution, it claims to reconcile the claims of modern science with what seems so obvious to so many--that there is an intelligent force or being in the universe that has guided the design of this universe. Michael Behe is considered by some to be the father of the intelligent design movement. His first book, Darwin's Black Box, was much maligned by scientists, yet intrigued and captivated many people, including many Christians. In that book, Behe claimed that at a biochemical level, many structures at the very foundation of life are irreducibly complex--they cannot have evolved by random chance but must, therefore, be the product of an intelligent designer. The scientific community largely criticized Behe's efforts, suggesting that he was simply taking advantage of the ignorance of the general reader when it comes to issues such as biochemistry and genetics. They consider him little more than a creationist who attempts to maintain some level of scientific integrity. In the words of Richard Dawkins, "He's a straightforward creationist. What he has done is to take a standard argument which dates back to the 19th century, the argument of irreducible complexity..."

In his latest book, The Edge of Evolution, Behe, still holding firm to his belief in irreducible complexity, goes looking for the edge, the border between what can be accounted for on the basis of random mutation and what cannot. He looks for the division between what could evolve and what must have required the intervention of a designer.

To understand Behe's argument, the reader must be willing to delineate three separate ideas that together form Darwin's theory of evolution: random mutation, natural selection and common descent. When most people think of evolution, they think primarily of random descent--that all living creatures evolved from a common ancestor. Yet this idea accounts only for the similarities in creatures, not their differences. To account for differences one must look to random mutation and natural selection. After all, we would expect that everything stemming from a common ancestor would bear great similarities. Since this is not the case something must have intervened and here the evolutionist turns to mutation and selection. Natural selection is quite innocuous as it merely suggests simply that organisms which are more fit will produce more offspring that organisms that are less fit. Thus the heart of the Darwinian theory is the role of random mutation--that certain organisms become stronger or more fit because of random mutations. Until these mutations occur, random selection can do nothing.

Because these concepts are unrelated, they must be considered independently rather than as a whole. Rather than providing an exhaustive treatment of each, Behe summarizes what he considers the rational positions based on modern science. First, there is compelling evidence for common descent; second, there is good evidence that random mutation paired with natural selection can modify life in important ways; third, there is strong evidence that random mutation is extremely limited. Thus Behe grants common ancestry and natural selection, and grants that mutation coupled with selection can change life. But where he draws the line is at the power of random mutation and natural selection. This, he says, has been greatly oversold to the public. And so the purpose of this book is "to cut through the fog, to offer a sober appraisal of what Darwinian processes can and cannot do, and to find what I call the edge of evolution." He attempts to define a set of guidelines that will mark the furthest extent of what Darwinian evolution can account for.

Because of their rapid generation times, much of the book centers around studies of Malaria and other tiny organisms. Though the amount of technical information can be a bit intimidating, Behe does a good job of making the concepts make sense to amateurs like myself. Out of pure necessity he often relies on the phrase, "In other words..." As he begins to delimit the edge of evolution, Behe proposes two criteria by which to judge whether random mutation combined with natural selection is a reasonable explanation for a molecular phenomenon. First, he speaks of steps and says that the more intermediate evolutionary steps needed to achieve a biological goal, the less likely it is to be adequately explained in Darwinian terms. Second, he speaks of coherence suggesting that a telltale sign of planning is the ordering of steps towards a particular goal whereas random mutation is, by its very nature, incoherent. Through multitudes of examples he attempts to prove his thesis and then turns to answering the anticipated objections to it. He arrives at the conclusion that "the molecular developmental program to build an animal must consist of many discrete steps and be profoundly coherent." Thus many animal forms have necessarily been designed. But to what degree?

Finally Behe comes to the moment of truth where he must attempt to define the outer edge of Darwinian evolution. "[We] can conclude that animal design probably extends into life at least as far as vertebrate classes, maybe deeper, and that random mutation likely explains differences at least up to the species level, perhaps somewhat beyond. Somewhere between the level of vertebrate species and class lies the organismal edge of Darwinian evolution." Combining this book with Darwin's Black Box, then, we are left to see that the major "architectural features of life--molecular machinery, cells, genetic circuitry, and probably more--are purposely designed." But the architectural constraints leave room beyond this for plenty of variation and adaptation.

The reader is then left wondering in what ways this intelligent force interacts with the world and how it acts as designer. Here Behe has little to offer, though he does offer the information that he is a fairly traditional Roman Catholic and that, in his view, this designer is God, but a God who functions much like a watchmaker, setting the world in motion and then stepping back to let it run its course. "Those who worry about 'interference' should relax. The purposeful design of life to any degree is easily compatible with the idea that, after its initiation, the universe unfolded exclusively by the intended playing out of natural laws." He is careful, though, to point out that one does not to believe in God, or the God of the Bible, to accept intelligent design. The evidence of design is, after all, visible in every area of nature. Whether or not a person accepts that there is a God, he must come up with some concept of a creator. Thus Behe's understanding of intelligent design is perfectly compatible with the idea of universal common descent. But it is entirely incompatible with Darwin's mechanism of evolution--random variation and natural selection.

As much as I enjoyed reading this book (and I truly did!) I must disagree with Behe in several areas. For all his talk of common descent, Behe is unable to provide a single convincing example of anything of the sort. Watching countless thousands of generations of various organisms has yielded only other like organisms. Science has still been unable to show that one organism can become another. After countless iterations, Malaria is still Malaria; a fly is still a fly; a monkey is still a monkey. He gives no new or compelling evidence of macro-evolution. Thus I have to reject common ancestry as an evolutionary myth that is completely at odds with the biblical account of creation. With Behe, as with so many scientists, common descent is assumed but unproven.

Also, his conclusions regarding the person or nature of the designer were entirely unsatisfactory and it seemed that he was perhaps unwilling to pay the cost of declaring that God, and only God, could be the designer. As a committed Catholic he must believe this. Why, then, would he give such leeway to believe it could be any other force? And how, as a Catholic, could he suggest that God is now watching the world from afar as it runs its course on the basis of natural laws. When he does attempt to address difficult issues, he still falls short. Though he affirms that we have to conclude that something as nefarious as Malaria was intentionally designed, he does not draw satisfactory conclusions about the kind of designer who would design such a thing.

Behe gave little guidance on just how the designer interacts with the creation. How does this person or force function as designer today? Does he simply make the mutations happen that are otherwise mathematically impossible? Or does he express his will in some other way?

As the evolutionary camp fractures into various factions, and as evidence continues to mount proving that the theory is rife with scientific and logical inconsistencies, those who believe in the the biblical account would do well to read such books and to learn from them. They must be read with caution and discernment, but when read carefully they can unearth a wealth of information that looks at the very building blocks of life and shows the hand of the creator as clearly there as anywhere else.