Evolution vs. Intelligent Design
Scientific evidence that God is in the details
by Richard A. Wiedenheft

The theory of evolution by natural selection has dominated the scientific world for almost a century and a half. And while most evangelical Christians have always disparaged and dismissed the theory, their arguments have done little to loosen its grip on the thinking of most scientists, educators, and millions of their students.

But now evolution is being challenged on a new front by scientists themselves--not necessarily Chris-tians--who are part of what is called the Intelligent Design (ID) movement. They claim that evolution simply cannot explain the incredible complexity and exquisite pattern so apparent in the natural world. On the contrary, these could only be the result of intelligent design.

The roots of this movement can perhaps be traced back to a book written in 1984 by three scientists. These men challenged the validity of experiments that supposedly demonstrated that life could have arisen by chance from some primordial soup. Near the end of their book they write:

A major conclusion to be drawn from this work is that the undirected flow of energy through a primordial atmosphere and ocean is at present a woefully inadequate explanation for the incredible complexity associated with even simple living systems, and is probably wrong. and is probably wrong.1

In his 1996 book Darwin's Black Box, Michael Behe, professor of biochemistry at Lehigh University in Bethlehem, Pennsylvania, puts it this way:

The simplicity that was once expected to be the foundation of life has proven to be a phantom; instead, systems of horrendous, irreducible complexity inhabit the cell. The resulting realization that life was designed by an intelligence is a shock to us in the twentieth century who have gotten used to thinking of life as the result of simple natural laws.2

Irreducible complexity

One of the cornerstones of Behe's arguments is the concept of irreducible complexity. A system or a mechanism can be reduced to a point beyond which it becomes a pile of junk. He uses the example of a mousetrap: It is so designed that removing any one of its five essential parts renders it utterly useless for catching mice. Either all the parts are present, properly connected, and functioning, or the mousetrap doesn't work.

I like to illustrate this principle with a car. It's full of devices and decorations that aren't essential for transportation. The radio, the windows, and the chrome bumpers could theoretically have been added over a long time by gradual improvements and changes to a functioning car. But remove one of the four wheels or the steering wheel or the flywheel, and you've got an expensive pile of junk that won't go anywhere.

All the essential parts of an automobile have to be in place and operating together at the same time, or it won't function at all as a means of transport. You can't have a partially evolved automobile that limps along somehow without any steering control mechanism until some evolutionary process just happens to create a steering wheel that just happens to be capable of transferring its rotation to moveable wheels on the ground!

Geoffrey Simmons, M.D., calls this "all-or-none," or the "whole-package phenomenon (WPP)."3 The whole package has to be in place, or nothing gets accomplished.

The living world is full of "whole packages"--intricate yet irreducibly complex mechanisms and processes. These present a huge problem for the theory of evolution, which posits that complex forms of life can develop step by step from simpler forms, gradually adding functionality as they become more and more complicated. As Behe says:

An irreducibly complex system cannot be produced directly... by slight, successive modifications of a precursor system, because any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional.4

Even Charles Darwin recognized this "Achilles' heel" of his theory. Behe quotes from The Origin of the Species: "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."5

In Darwin's day, however, scientists were just beginning to recognize that living organisms were made of cells, which they understood little about. The cell was an unknown or, as Behe terms it, a "black box." The presumption was that once they came to understand the cell, scientists would find simple structures and processes that would support the theory of evolution.

"Simple" cells

When I studied biology in high school and college in the 1960s, teachers talked of simple cells and simple one-celled animals. The thinking was that amino acids somehow developed into uncomplicated functioning cells, which eventually adapted to their environment to become more complicated cells, which developed into multi-cellular plants and animals—and on and on until all the life forms as we know them today were developed. So the theory went.

However, with the advent of the electron microscope in the mid-twentieth century, scientists could begin to open the "black box" of the cell. Around the same time, X-ray crystallography enabled researchers to determine the structure of various molecules, including complex protein molecules. These advances revealed far more complexity than anyone had ever imagined. The simplest of cells is anything but simple.

Geoffrey Simmons estimates that every cell contains one billion compounds including five million different kinds of proteins, each one having a unique shape and characteristics that enable it to play a specific role in the body. In addition, there are more than 3,000 enzymes critical to chemical reactions that take place in the body. Cells come in many varieties and shapes; they serve many different and specialized functions in the body. Some cells work as individuals floating in the blood; others connect with identical cells to form skin or muscles, for example. Still others send out long extensions to communicate with other cells.6

When one looks into the workings of any one cell, he finds incredible complexity.

The "simplest" self-sufficient, replicating cell has the capacity to produce thousands of different proteins and other molecules, at different times and under variable conditions. Synthesis, degradation, energy generation, replication, maintenance of cell architecture, mobility, regulation, repair, communication--all of these functions take place in virtually every cell, and each function itself requires the interaction of numerous parts.7

Behe likens all this activity, accomplished at the molecular level, to the workings of machinery:

... life is based on machines—machines made of molecules! Molecular machines haul cargo from one place in the cell to another along "highways" made of other molecules, while still others act as cables, ropes, and pulleys to hold the cell in shape. Machines turn cellular switches on and off, sometimes killing the cell or causing it to grow. Solar-powered machines capture the energy of photons and store it in chemicals. Electrical machines allow current to flow through nerves. Manufacturing machines build other molecular machines, as well as themselves. Cells swim using machines, copy themselves with machinery, ingest food with machinery. In short, highly sophisticated molecular machines control every cellular process. Thus the details of life are finely calibrated, and the machinery of life enormously complex.8

In other words, the simplest cell is a veritable factory of molecular machines, and evolution offers no mechanism whereby this factory could have gradually assembled itself over long periods of time.

Conceptual precursors are not physical precursors

Behe faults evolutionists for failing to look at the details when they postulate how, for example, a single-celled animal with a light-sensitive spot could, over a very long time, develop into an eye. The light-sensitive spot might be a conceptual precursor to an eye, but when one looks at all the chemical systems in the eye, there is no way the light-sensitive spot could be a physical precursor to the eye.

As an illustration, consider the bicycle as a conceptual precursor to a simple motorized bike. One could postulate that somehow the bicycle gradually developed into a motor bike. But looking deeper, one discovers that this progression simply cannot happen gradually. The motor, for example, is an entire irre-ducibly complex system consisting of hundreds of parts. If any one part is missing (a spark plug, for example), the motor is useless. And even if the motor were somehow available in an evolutionary junkyard, it would have to be securely mounted on the frame, and somehow transfer its energy to a drive sprocket, which would somehow get connected to a wheel sprocket in order to make a wheel turn. Then there's the problem of fuel, carburetion, and a starting mechanism. Without all the parts fully assembled, the motor bike won't function at all. Gradually adding some parts without the others results in a more cumbersome conveyance that is less functional than the original bicycle.

The bicycle may help us to conceive of, to conceptualize, a motor bike, but it cannot be a physical precursor to a motor bike. Similarly, the light-sensitive spot may be a conceptual precursor to an eye, but it would have to add many complex functions and biochemical processes, each of them irreducibly complex, in order to function as an eye. Evolution is based on the assumption of physical precursors. But the natural world offers irreducibly complex systems that function only as a whole and that could have come about only by Intelligent Design.

An example: cilia

For us non-biochemists, the details of how the body functions at the molecular level can be hard to grasp. But it is in the details that evolution faces its greatest challenges, and it is in the details that we can see the marvel of a creation that cries out for intelligent design.

One example of an irreducibly complex system, detailed by Behe, is cilia—cells with hair-like extensions that can move like a whip. The respiratory tract is lined with cilia, helping expel mucus. Sperm cells are mobile and have cilia to swim. These apparently simple cells are actually complex molecular machines.

If you cut through a cilium and examine its cross section under great magnification, you discover that it is composed of a number of tiny tubes, or microtu-bules. Just inside the "skin" of the cilium is a circle of nine pairs of these tiny tubes. In the middle of the cilium is yet another set of two microtubules linked to each other. All the microtubules are, in fact, cylinders made up by a circle of even smaller strands or fibers.

The current understanding of biochemists is that the motion of the cilium depends on two protein molecules that go between a microtubule of one pair and one of the microtubules of the pair next to it. One of these proteins is dynein, the "motor" of the cilium. The other is nexin, which serves as a link or tie between the adjacent pairs.

Under the right circumstances, the dynein pushes against the molecules in the microtubule next to it so that the two tend to slide past one another. In fact, if the microtubule pairs weren't tied together by the nexin, the dynein molecules would just keep pushing the adjacent tubule along like a telescoping antenna until they reached the end. But the nexin connectors prevent that from happening. With the dynein pushing and the nexin holding, the microtubules bend. This action of all the dynein motors pushing over and over again and all the nexin linkers holding on tight is apparently what makes cilia whip and the cell move.

This is a simplified explanation of an intricate mechanism, one that, according to Behe, is irreducibly complex.
All of these parts are required to perform one function: ciliary motion. Just as a mousetrap does not work unless all of its constituent parts are present, ciliary motion simply does not exist in the absence of microtubles, connectors, and motors. Therefore we can conclude that the cilium is irreducibly complex—an enormous monkey wrench thrown into its presumed gradual, Darwinian evolution.9

The Clotting of Blood

When you get cut, your life depends on the ability of your blood to quickly form a clot before all your blood drains out. Just as important, it has to stop clotting when the bleeding is stopped, and it has to not clot when there's no wound! That seems like a relatively simple assignment, but it is not. On the contrary, the body's mechanism for controlling blood clotting is a marvelous and intricate series of chemical reactions that is irreducibly complex. Remove any one of the elements, and blood clotting simply doesn't work.

Fibrogen is the protein that is used to make up the web, or mesh, of "fibers" that plays a vital role in clot formation. Normally, it just floats around in the blood. In order for it to get involved in clotting, fibrogen has to be altered by another protein, thrombin, which lops off small pieces of the fibrogen molecule to expose "sticky patches." This new molecule is called fibrin. Its sticky patches fit into portions of other fibrin molecules so they begin to form long strands that cross over one another to form a web that traps blood cells.

But what keeps the thrombin from lopping off the ends of the fibrogen molecule all the time creating one massive blood clot? The answer is that thrombin molecules float around in the bloodstream in an inactive form called prothrombin. It takes another protein, called Stuart's Factor, to activate prothrombin. But what keeps Stuart's Factor from activating prothrombin all the time? That involves yet another protein molecule, accelerin, which exists in an inactive form until it is activated by—well, you get the picture!

In all, there are some twenty chemicals involved in the cascade of reactions that quickly swings into action when the body is wounded. The clotting mechanism first forms a soft clot to stop the flow of blood. Then it turns off the clotting process, then converts the fragile soft clot into a hard one that is more durable. Finally, when the wound is healed, it breaks up the clot. All the chemicals involved are essential to the process. If any one is missing, the entire process fails to work. Hemophiliacs, for example, can't stop bleeding because their blood lacks one of these essential factors.

Referring to the effort of one scientist to explain how this blood clotting cascade could have evolved gradually, Behe wrote:

The fact is, no one on earth has the vaguest idea how the coagulation cascade came to be.... Blood coagulation is a paradigm of the staggering complexity that underlies even apparently simple bodily processes. Faced with such complexity beneath even simple phenomena, Darwinian theory falls silent."10

Other examples of complexity

Behe details other examples of irreducibly complex systems in the body, including the seemingly simple task of moving proteins created in one part of a cell to another part of the cell where they are needed. One method, which he calls a "mind-boggling process," is vesicular transport

... where protein cargo is loaded into containers for shipment [from one part of the cell to another].... An analysis shows that vesicular transport is irreducibly complex, and so its development staunchly resists gradualistic explanations, as Darwinian evolution would have it.11

Simmons cites insulin production as a process that is irreducibly complex as well:

In the process of insulin manufacture, none of the several "pre-insulin" molecules are useful (envision a car being made along an assembly line). Not only is this an all-or-none process, but so are the mechanisms that tell the body when to secrete insulin, how much insulin to produce or secrete, for how long, where to send it, how to link it to nutrients in the blood, how to transport it, and how to turn it off when the job is done.12

Then, there's the body's immune system and the manufacture of AMP, a form of one of the four building blocks used to make up DNA. These are all very complicated, yet irreducible; and evolutionists offer no explanation as to how they came about.

What does it all mean?

In his conclusion, Behe writes about the implications of all the knowledge about cell structure and function that has been accumulated over the past four decades.

The result of these cumulative efforts to investigate the cell--to investigate life at the molecular level— is a loud, clear, piercing cry of "design!" The result is so unambiguous and so significant that it must be ranked as one of the greatest achievements in the history of science.... The observation of the intelligent design of life is as momentous as the observation that the earth goes around the sun or that disease is caused by bacteria or that radiation is emitted in quanta.... But no bottles have been uncorked, no hands slapped [to celebrate this discovery]. Instead, a curious, embarrassed silence surrounds the stark complexity of the cell.... Why does the scientific community not greedily embrace its startling discovery? ... The dilemma is that while one side of the elephant is labeled intelligent design, the other side might be labeled God.13

Behe finds this rather odd given the fact that 90 percent of Americans say they believe in God and about 50 percent attend religious services every week and that you regularly hear references to God from politicians and sports stars.

But the apostle Paul would certainly not have been surprised. He wrote almost 2,000 years ago of those who "did not like to retain God in their knowledge" (Romans 1:28). And while the intelligent design movement is a serious challenge to evolution, I don't think we should be optimistic that Darwin's theory will collapse anytime soon, nor that large numbers of scientists will embrace God as the Intelligent Designer. The mainstream of society didn't pay much attention to God before Darwin, and I doubt it will pay much attention after his theory is relegated to the footnotes of the history of science.

On the other hand, Christians can have greater confidence that our belief in God is not based on a blind faith that is in conflict with science. On the contrary, we can glorify God with the psalmist: "I praise you because I am fearfully and wonderfully made; your works are wonderful, I know that full well" (Psalm 139:14, NIV). With every advance of science in understanding the intricate design of the creation, we know more and more "full well" how wonderful the Creator is.

For since the creation of the world God's invisible qualities—-his eternal power and divine nature—-have been clearly seen, being understood from what has been made, so that men are without excuse (Romans 1:20).

The more we learn of the exquisite, fantastic design of the creation, the more clearly we can see the magnitude of the Creator's eternal power and majesty!

TSS

July / August 2005 The Sabbath Sentinel