CREATION/EVOLUTION DEBATE
SERMON EIGHT PRESENTED ON 11-21-20
Last time we were together we discussed a number of issues that pertain to the creation/evolution debate. We again looked at the young earth creationist’s view that the earth and all its life forms go back no more than 6 to 10 thousand years. I discussed the formation of stalactites and stalagmites and showed how it takes tens of thousands of years for these formations to get to the level we see them at in caves around the world. Like the star light problem discussed in a previous sermon, this phenomenon presents a series challenge to the young earth perspective.
We discussed in depth the issue of macro and micro evolution and speciation. We discussed how if an organism is able to breed with another organism and produce offspring which are reproductively able to produce the same breed or a breed with similar characteristics, both such organisms are considered to be of the same biological species. You may remember I used the horse, donkey and mule example to demonstrate this phenomenon.
We then looked at various dynamics associated with the development of life forms. We looked at abiogenesis versus biogenesis, comparative anatomy, comparative blood types, comparative embryology and homology. We discussed how evolutionists believe these dynamics of life forms show us that all organisms have gradually evolved over millions of years. I then proceeded to show the problems with that conclusion.
Today, I want to discuss the concept of irreducible complexity. The term irreducible complexity was introduced by biochemistry professor Michael Behe in his book, Darwin’s Black Box. Behe defines irreducible complexity as “a single system composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning." Mr. Behe goes on to say:
"An irreducibly complex system cannot be produced directly by numerous, successive, slight modifications of a precursor system, because any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional..... Since natural selection can only choose systems that are already working, then if a biological system cannot be produced gradually it would have to arise as an integrated unit, in one fell swoop, for natural selection to have anything to act on" (Page 39, Darwin’s Black Box).
Behe is saying that for a particular body part to work in a certain way, it must have all its component parts present at the same time. Its component parts cannot gradually evolve into existence as is taught by classical evolutionary theory. They must all appear at the same time for the body part to properly work. It cannot work if it is missing a component. It cannot work in the manner it must in order to facilitate a particular function if it is reduced to less than what it is. Therefore it is an irreducible complexity.
As an illustration, Mr. Behe uses the mouse trap which is composed of a platform, hold-down bar, hammer, spring and catch. If the mouse trap was missing its base or its hammer, it could not function as a mouse trap because it takes all five parts, working together, to catch a mouse. Its five part structure cannot be reduced and still have it function as a mouse trap. Therefore, the mouse trap is an irreducible complexity. You can’t reduce it to less than what it is in order for it to work. It could not come together gradually and function as a mouse trap.
For it to catch mice, all its parts must be present at the same time. A precursor mouse trap consisting of only a hammer, base, catch and holding bar but having no spring would not catch mice. Such a precursor mouse trap would be non functional as a mouse trap.
If a mouse trap was a mechanism of a living organism, it could not be working as a mouse trap if one or more of its five parts were missing. Since natural selection, as part of the evolutionary process, can only choose a system that is already working, it would not choose a non functional mouse trap. The mouse trap would have to be fully functional in order to be of use to an organism and therefore be selected in an evolutionary process. Therefore, all the parts of a mouse trap would have had to come together at the same time in order to be a functioning mouse trap.
However, this goes against evolutionary teaching. Evolution teaches that biological organisms came into existence through gradual and random development of the various components that make up its parts. Behe is saying evolution could not be responsible for structures illustrated by the mouse trap. Such structures must have all their parts present at the same time in order to work. The components of irreducible complexities could not have evolved into such complexities. All their components must appear at the same time. This, however, is not how evolution is seen as working.
In his book on the origin of species, Charles Darwin used the terms "numerous, successive, slight modifications" in describing the conditions that had to be met for his theory to be true. Darwin wrote that if one could find an organ or structure that could not have been formed by "numerous, successive, slight modifications," his theory would absolutely break down." It is felt by creationists that the identification of irreducible complexities is a decisive blow to Darwinian theory.
Classical evolutionists believe that biological organisms came into existence through gradual and random development of the various components that make up the systems/structures that make up organisms. For example, there are hair-like structures on the surface of cells called cilia that move fluid across the surface of cells and help move a cell from one place to another. In human anatomy we see such structures lining the respiratory system where they help sweep mucus into your throat for elimination. You will also fine them in the digestive tract where they play a vital role in the absorption of nutrients.
Classical evolutionists see these cilia coming to be and doing what they do as a result of fortuitous molecular activity occurring incrementally over millions of years of evolutionary development. Michael Behe sees cilia as an irreducible complexity that must have been designed to be and do what it does.
Cilia, as simple as they appear to be, are rather complex structures made up of around 200 protein parts. Included in their complex makeup are nine pairs of microtubules (long thin flexible rods) which encircle two single microtubules. The outer microtubules are connected to each other by a structure called a nexin linker. Each microtubule has a motor protein structure called a dynein which attaches to one microtubule and has an arm that reaches over and grabs the dynein of another microtubule and pushes it down. These two rods start to slide lengthwise in relation to each other. The nexin linkers, which start as loose rope like structures, get stretched and become tight. As the dynein pushes farther and farther, it begins to bend the hair-like structure and then pushes the other way to bend it back. This is how you get the wave like motion of cilia.
According to evolutionary theory, the cilia would have had to gradually come into existence through small incremental structural changes taking place over a long period of time. The problem is that unless the rods, linkers and motor proteins, along with the many other parts of the cilia are all present at the same time, you don’t have working cilia. You don’t even have cilia. Cilia, by definition, are complete complex structures that include rods, linkers, dyneins and a great deal more. You can’t reduce this complexity to less than what it is and still have working cilia. Thus you have irreducible complexity. You can’t reduce the complexity of something and still have it do what it is suppose to do. If it can’t do what it is suppose to do, it reduces or makes impossible the workability of the organism as a whole.
In Behe’s most recent book, “The Edge of Evolution,” he discusses the cilia of a certain single-celled algae. Through a high powered microscope, it was discovered that moving up one side and down the other side of the cilia were a series of “bumps.” Further study of theses bumps revealed they are the machinery that builds and maintains the cilia. If a cilium is cut off an algae cell, another one will be generated in an hour or so by this machinery.
This machinery operates throughout the lifetime of the cilia and routinely brings in new copies of cilia components while removing old material. In a several hour period, over eighty different kinds of proteins are exchanged. There are motor proteins responsible for carrying particles up and down the cilium and for a variety of other cilium functions. It has been demonstrated that the proper maintenance of cilia is very important to the function of an organism. For example, a genetic mutation of one of the proteins in the cilium machinery can cause cilia to lack a certain part resulting in the cilium not working and causing infertility and chronic sinusitis in human males.
As already covered, the cilia must have all its parts present at the same time in order to work in a beneficial manner. The parts of cilia have several hundred proteins. All these proteins must be present at the same time in order for the parts of the cilia to be properly assembled. This type of complexity is true of all life. Therefore, we have irreducible complexity not only of the parts of the cilia but also of the molecular components that produce the parts. In order for cilia to be made and be maintained, its molecular structure must also be in a state of irreducible complexity. All its molecular components must be present at the same time and in a particular configuration in order for cilia to be made, exist and function.
Mathematical probability studies have demonstrated that this kind of simultaneous accumulation of specific components could not be achieved through random mutation and natural selection as is taught by evolution.
Random mutation and natural selection have no conscious goal. There is no focus in the random expression of genetic material. Mathematically, there are so many directions molecular components could travel that the probability of just the right ones randomly coming together to facilitate a specific irreducible complexity is mathematically impossible. Therefore, creationists believe the existence and necessity of irreducible complexities negates the Darwinian process of gradual development of molecular structures and their derivatives.
Proteins have been found to have complex shapes and must fit into the shapes of other proteins to make possible the working of cellular machinery. Therefore, proteins work together to facilitate a particular result. It has been determined that nearly every major process that takes place in a cell is facilitated by an assembly of ten or more protein molecules interacting with additional assemblies of protein molecules. Therefore, the cell is a virtual factory of interacting assembly line workers all needing to be simultaneously present to complete a task. Such required synergy of activity shows the impossibility of all this coming about through unintelligent, random and aimless processes.
Michael Behe points to certain bacteria that have a swimming device called a flagellum and are able to move about by rotating their flagellum much like a rotating propeller. The energy required for this function is generated by a flow of acid through the bacterial membrane. The flagellum is composed of a paddle, a rotor and a motor mechanism. It needs all three plus the energy making system in order to work. A lack of any one or more of these devices makes the flagellum inoperable. Mr. Behe sees this as an irreducible complexity.
Creationists see in irreducible complexity the impossibility of the gradual development of the thousands of structures that make up living organisms. Complete development of such structures is seen as being required to facilitate the workability of the structure and in turn facilitate the survival of the organism. The human eye is often used as an example.
The human eye is enormously complicated - a perfect and interrelated system of about 40 individual subsystems, including the retina, pupil, iris, cornea, lens and optic nerve. For instance, the retina has approximately 137 million special cells that respond to light and send messages to the brain. About 130 million of these cells look like rods and handle the black and white vision. The other seven million are cone shaped and allow us to see in color.
The retina cells receive light impressions, which are translated to electric pulses and sent to the brain via the optic nerve. A special section of the brain called the visual cortex interprets the pulses to color, contrast, depth, etc., which allows us to see "pictures" of our world. Incredibly, the eye, optic nerve and visual cortex are totally separate and distinct subsystems. Yet, together, they capture, deliver and interpret up to 1.5 million pulse messages a mille-second! It would take dozens of Cray supercomputers programmed perfectly and operating together flawlessly to even get close to performing this task.
Evolutionary theory postulates that random processes, operating through gradual mechanisms of natural selection and genetic mutation, produced the highly complex 40 separate subsystems that make up the even more complex functional eye. Creationists point out that if all the separate subsystems of the eye aren't present and performing perfectly at the same instant, the eye won't work and has no purpose. These subsystems provide no advantage to the whole until they all appear together at the same time.
Since these subsystems of the eye have no functional purpose on their own in separation from the whole, it is asked why they would evolve in the first place. Creationists see the only logical explanation to be that all structures that make up the eye appeared at the same time and could not have evolved. Creationists conclude that irreducible complexity cannot evolve and therefore can only be attributed to an intelligent designer and creator.
The Evolutionist response:
Evolutionists have observed that simpler organisms have simpler eye structures and therefore postulate there was a gradual development from simple to complex eyes over time.
However, this view has been largely negated as paleontologists have discovered that the so-called simple organisms emerged into the world with complex structures already intact. Even the simple trilobite, which is considered by evolutionists as one of the first organisms to evolve, has a very complex eye structure. This same phenomenon is seen in countless other structures of so-called simple biological organisms.
Evolutionists respond to the postulation of irreducible complexity by suggesting such structures could have evolved in response to genetic variation and/or environmental influence (natural selection). They point to the Venus flytrap as an example of irreducible complexity evolving.
This plant is a member of one of the largest genera of carnivorous plants called sundews, having over 170 species. Sundews are found on every continent except Antarctica. The species Venus flytrap has a tooth-edged trap which catches insects and digests them. When an insect brushes against the trigger hairs in the center of the trap, the lobes snap shut and the insect is digested over the next few days. The trap is made up of two lobes, the hinge between the lobes (the midrib of the leaf, which anchors the lobes), the trigger hairs, and spines projecting from the edges of the lobes that make a set of bars as the trap closes. All these parts are needed to make the trap work. Therefore, it is an irreducible complexity.
There are other species in these genera which trap insects. Some do so by having a sticky surface on their leaves. Once an insect gets stuck, the leaves of the plant slowly fold around the insect and ultimately digest it. Others, not having as sticky of a surface, close their leaves a lot faster to trap an insect. All the different mechanisms these plants have to trap insects are in themselves irreducible complexities as all their parts must be present for the insect catching phenomenon to work.
In comparing sundews that trap insects with a sticky surface with the Venus flytrap which gobbles up insects with teeth, evolutionists see evolution in action. They see a gradual movement from a less sophisticated method to a more advanced method of trapping insects. While evolutionists agree that all the components of a particular part of an organism must be present at the same time for such component to properly work, it is believed that such components evolved into coming together and once together form the irreducible complexity. Therefore they see evolutionary development from plants that can only trap insects by secreting a sticky substance to the Venus flytrap which developed teeth to trap insects.
Creationists respond by pointing out that if sundews evolved more sophisticated ways of catching insects, why haven't the species or varieties with less sophistication long ago died out? Natural selection postulates that organisms have evolved from simple to complex with the more complex eliminating the less complex. If movement from simple to complex and survival of the fittest (natural selection) is the goal of evolution, why are there still many organisms within a species or variety of a species with less complex structure still existing and reproducing? If such less complex structure was sufficient for survival, why evolve into something more complex?
Behe challenged:
Some evolutionists have taken issue with Behe’s use of the bacterial flagellum to promote his position that evolution could not have produced this irreducibly complex system. Evolutionists show they have found parts that exist in the flagellum to also exist in the components of parts of other organisms where they are perfectly functional within such parts. Therefore, they have concluded that such components could have evolved from one organism to another over time.
However, Behe is not saying that the individual components that that make up the parts of the irreducibly complex flagellum can’t also make up parts of other organisms. What he is simply saying is that a flagellum cannot be functional if it is missing one of its parts. You can’t have a partial flagellum work in the manner that a whole flagellum works. Only a whole flagellum can facilitate movement of a bacterium in the manner that it does. Therefore, it is an irreducible complexity. It would have to come together all at once to function in the way it does. Evolution would have had to bring all the parts together at the same time to make the flagellum work the way it works. The chances of this happening and happening repeatedly have been found to be highly improbable.
Evolutionists respond that a flagellum with fewer parts could have preceded the fully equipped flagellum allowing for a different kind of movement of the bacteria in the historical past. They point to Behe’s mouse trap illustration. You can modify the mouse trap by removing the catch and hooking the holding bar to the end of the spring mechanism and it will still snap to kill mice. Therefore, Behe’s mouse trap is not irreducibly complex. Behe readily admits there are other mouse traps that will catch mice but if you want one to work in the specific manner in which the trap he uses as an illustration works, all its parts must be present at the same time. The same goes for the flagellum, cilia and thousands of other structures that must have all their parts present at the same time in order to work in the manner that they work.
Evolutionists agree but maintain that in the biological world there is constant development of new molecular structures as living organisms expand into multiple millions of varieties. It is maintained that as genetic changes take place and natural selection exerts it influence on survival of livings organisms, molecular complexities gradually develop over time to facilitate particular functions only to be replaced by other molecular complexities as evolutionary development continues.
Atheistic evolutionists maintain that if you are going to insist that irreducible complexity results from the activity of a designer, then that designer must be constantly at work designing new molecular structures as new molecular structures are constantly occurring as mutation and natural selection lead to new varieties of organisms on a continuous basis. Progressive creationists, a category of creationists I have previously discussed, actually believe God has been and still is creating new organisms.
Evolutionist don’t’ deny irreducibly complexity. They readily admit that a particular part of a living organism can only work in a certain way based on the way in which the t components of such part have come to be arranged. In that respect it can be identified as an irreducibly complexity. However, atheistic evolutionists insist that components that make up the parts of living organisms only become irreducibly complexities through evolutionary processes and not through design by a supernatural agent.
As I have said several times in this series, I am not out to show that evolution doesn’t occur. All strips of creationists admit to evolution occurring in some manner and to some degree. The disagreements occur as to in what manner and to what degree evolution occurs. Did it start with God beginning the evolutionary process in the primordial past and simply letting it fly? Did it start after an initial creation of different kinds of living organisms as seen in the Genesis creation account and it is from those basic kinds that multiple millions of organisms have evolved? Is God still actively involved in creating new organisms as some creationists believe? Are there other dynamics involved in the appearances of new organisms in addition to genetic mutation and natural selection? These are the questions we will continue to explore as we proceed with this series.
Let's review:
Classical evolutionists believe irreducibly complex structures have evolved like all other biological components. They see organisms gradually developing structures composed of various parts which become irreducible complexities in so much that such structures must have all their parts working together to produce a particular function at that point in the organisms evolutionary development. As organisms continue their evolutionary progression, parts and components of parts continue to evolve into more advanced irreducible complexities. Therefore, evolutionists see no need to view development of irreducible complexities any different from evolutionary development in general.
Creationists counter that since all component parts of a system or structure must be present at the same time for a particular function to work, it is highly improbable that such parts would all come together at the same time through natural selection and/or genetic mutation. When considering the multiple numbers of irreducible complexities that can be identified in any given organism, the probability that they all came together at the same time is astronomical. Furthermore, it is pointed out that there are no transitional forms in the fossil record to show evolving irreducible complexities. While evolutionists like to point to certain organisms as transitional life forms in the geological record, creationists maintain that the fossil record only shows completely developed biological entities with completely developed structures, including what can be defined as fully developed irreducible complexities.
Next week we will discuss the development of man.