“Darwin abhorred” (Michael Behe)

DEVOLVED

Persons sometimes hold two jobs simultaneously, but no one has a more oxymoronic dual employment than Dr. Michael Behe. He serves as a fulltime a scientist for Lehigh, where he is a biochemistry professor. Meanwhile, his moonlighting gig is as a pseudoscientist for the Discovery Institute, where he argues against a specific plank of evolution.

Behe differs from most creationists, partly because he is of the Old Earth variety, a comparatively rare subspecies. More significantly, he acknowledges that life has evolved over billions of years and that all living organisms have a common descent. He also acknowledges that mutation and natural selection drive the processes that lead to the diversity of life. All this, in fact, capsulizes the theory of evolution. But Behe veers sharply from the scientific landscape when he proposes that there is an intelligent design mechanism which is causing the genetic changes that enables evolution. He stresses that point repeatedly in his latest book, Darwin Devolves.

In this work, Behe insists that mutations can only make things worse, absent intelligent intervention. This is consistent with his longstanding belief that anything science cannot completely figure out means that his god is responsible. This is the God of the Gaps gaffe and is a common pseudoscience error.

Behe makes no attempt to falsify the idea, nor does he give fellow scientists any experiments to try and replicate. He has not observed intelligent intervention in action, he makes no predictions about how it would function, and he subjects the idea to no peer review. In short, he offers zero science to support his claim that a deity is driving evolution’s key mechanism.

Compare that to what he expects of those with the opposing position. In an essay for skeptic.com, John Jay College professor Nathan Lents wrote, “Behe holds modern evolutionary theory to an impossible standard, declaring it insufficient if we cannot pinpoint every point mutation and every intermediate genetic step, all in the right order.”

Behe argues that mutation should be fatal to evolution because most genes that spark adaptation have been irreparably broken and have also been inactivated by mutations. And a dead gene, he says, tends to degrade further and can only be reactivated by a supernatural agent.

But biology professor Jerry Coyne writes that this position requires ignoring the following: Adaptive mutations which do not inactivate genes, including genes that are accidentally copied twice, with the copies diverging in useful ways; Changes in how and when a gene is turned on and off, such as mutations producing lactose tolerance in milk-drinking human populations; The repurposing of ancient genes acquired from viruses; Chimeric genes that are cobbled together from odd bits of DNA; And simple changes in DNA sequence that alter proteins without breaking them, such as is see in tolerance of low oxygen levels in geese.

Most importantly from a scientific standpoint, Behe only tries to find flaws in the other side instead of offering examples of designed mutations or providing evidence for a supernatural mechanism.

A key point to remember is that evolution never has an end-goal in mind. It’s about adapting to present conditions. It will even reverse course if that is advantageous. While the sci-fi concept of devolution, such as is seen with the Land of the Lost Sleestaks, is a cool one, it never happens in real life. In fact, a step-back is still evolution if that’s what the environment dictates.  

Behe tries to ride the coattails of Richard Lenski to make his case. Lenski oversees an ongoing, 30-year e. coli experiment that started with 12 originally-identical populations. These 12 experienced dramatically accelerated growth and showed a gradual loss of many abilities necessary to thrive in other environments. While this is literally observing evolution in action, Behe maintains it strengthens his position since none of the bacteria have developed creative new abilities.

However, these bacteria are in manufactured laboratory conditions and are not adapting to nature. And even in this environment which Lenski specifically designed to not prod bacteria toward new abilities, the cells have gained functions. Lents wrote that Lenski “has discovered variants of essential genes — not just dispensable ones — for the cell wall, DNA packaging and architecture, and a variety of tweaks that enhance, not diminish, the function of the encoded proteins. Perhaps the most exciting discovery is one culture’s new ability to import and metabolize citrate as a carbon source in an aerobic environment. This is all incredibly unlikely, as only one of the 12 cultures achieving this feat in more than 70,000 generations. This means random mutation has been seen to cause a new function.” That it could do this refutes Behe’s insistence that such a mutation requires divine intervention.

Let’s move from the lab to the outdoors and from the microscopic to what we can see with the naked eye. Behe touts Galapagos finches as an example of how animals can manage only incremental changes without supernatural assistance. He gloats that the birds have failed to develop the large-scale body redevelopment that occurred with organisms during the Cambrian Explosion.

The analogy is lacking since Cambrian diversification took more than 10 times as long and involved smaller, simpler, and faster-reproducing life forms. A larger issue is that when finches arrived on the islands, the Galapagos was already filled with other birds. This meant that the finches’ only path to success was stagnation. Diversification only occurs when animals fill unoccupied niches.

Lents pointed out that Madagascar lemurs provide a spectacular example of how this works. From the first pair 50 million years ago, we now have well over 100 species “including the smallest known primates and nearly the largest. There are burrowers, leapers, grazers, climbers, and everything in between. Lemurs have accomplished this because they were free to inhabit the ecological niches normally occupied by other animals. With no rodents on Madagascar initially, the mouse lemurs emerged. With no true sloths, we have the sloth lemur.”

This breadth of lemurs means the animal has achieved the taxonomic level of Family, something Behe claimed unguided evolution could never do. His retort was to feebly offer that this may have been made possible by “intelligently-provided information carried by the ancestor of lemurs.” He failed to explain how that hypothesis might be tested.

According Coyne, Behe’s rationale for designed mutations is circular. Behe claims biochemical pathways are designed rather than evolved because they’re based on a “purposeful arrangement of parts.” To this, Coyne asks, “Which arrangements are those designed with a purpose? They’re simply the pathways that Behe sees as too complex to have evolved. This is a classic example of begging the question, which is assuming what you’re supposed to prove.”

That last line, in fact, would work as a concise review of Darwin Devolves.

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