THE CREATION/EVOLUTION CONTROVERSY: PART SIX
In installment number six of this series, we will continue to examine how creationists and evolutionists view how life came to be. One of the strongest arguments creationists feel they have in support of intelligent design being responsible for biological organisms is what has come to be called irreducible complexity.
IRREDUCIBLE COMPLEXITY:
The term irreducible complexity was introduced by biochemistry professor Michael Behe in his book,
"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). Mr. Behe is essentially saying that irreducible complexities could not have evolved.
The phrase "numerous, successive, slight modifications" are the very same words used by Charles Darwin in The Origin of Species in describing the conditions that had to be met for his theory to be true.
Evolutionists believe that biological organisms came into existence through gradual and random development of the various systems/structures that make up plants and animals. 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.
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.
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 are 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 milli-second! It would take dozens of Cray supercomputers programmed perfectly and operating together flawlessly to even get close to performing this task.
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. 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. These subsystems, however, 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 in 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 this 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. Evolutionists see evolution of irreducible complexities within this genera through genetic variation. They see movement of plants from those that can only trap insects by secreting a sticky substance to the Venus’ flytrap which responds to the stimulus of an insect on its leaves and folds its leaves around the insect to entrap it.
Creationists respond that it is pure speculation that members of the sundew genera have evolved their different ways of catching insects. Each species in this genera has its own irreducibly complex structure for trapping insects. Creationists see no reason to believe that these structures gradually evolved into increasingly more complex structures. Creationists see this as another example of the comparative anatomy argument which proves nothings as to evolution. Comparative anatomy is discussed in part five of this series.
Furthermore, 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?
Another argument put forth to advance the contention that irreducible complexities can evolve is the development of bacteria that eat the highly toxic chemical pentachlorophenol (PCP). This is a man made chemical that began to be used in the 1930’s and is part of a class of chemicals called chlorophenols, some of which appear naturally in nature. The bacterium, S. chlorophenolica, uses three enzymes in succession to break PCP down and ultimately use it as a food. All three enzymes are necessary to accomplish this task so we have here an example of irreducible complexity as reducing to two or one enzyme would not get the job done.
It’s been found that two of these enzymes are produced by this bacterium in response to the presence of milder forms of chlorophenols which naturally occur in nature. The third enzyme involved is produced all the time and is always available. When PCP is present, this third enzyme combines with the other two enzymes to break down the PCP. This combining of the third enzyme with the other two enzymes is viewed as evolution of an irreducible complexity. Since PCP is a man made substance of recent date, some evolutionists believe a recent mutation changed the way this third enzyme is deployed which is what made PCP degradation possible for this bacterium.
Creationists point out that two of the enzymes only appear when chlorophenols are present. and only then do they combine with the third enzyme to break down the PCP chlorophenol. This suggests a genetically built in capacity to deal with chlorophenols. While it may appear that the manner in which the third enzyme is deployed is in response to the appearance of PCP in the environment, this has not been proven and may not be the case. The third enzyme may have always been deployed in the manner it currently is and may always have had the ability to combine with the two other enzymes to break down PCP. However, this complexing of enzymes would only take place when PCP appeared in the environment. This would not be evolution of an irreducible complexity but a manifestation of an irreducible complexity prompted by the presence of PCP. The ability of the bacterium to destroy PCP did not evolve but was always there. Yet in order to do so, the three enzymes have to work together to accomplish this task and therefore constitute an irreducible complexity.
Evolutionists have attacked Michael Behe’s statement that “any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional." Evolutionists claim nature is filled with examples of "precursors" to the flagellum that are indeed "missing a part," and yet are fully-functional.
Evolutionists point to certain bacteria having specialized protein secretory systems whereby they are able to secrete virulent material into a host cell. Molecular studies of proteins in such systems have found that the proteins that make up the system are similar to the proteins in the basal portion of the bacterial flagellum and have common chemical properties. It is pointed out that a small subset of the full complement of proteins in the flagellum makes up these specialized secretory systems. In other words, these bacteria do their work of secreting material into a host by using similar proteins as those found in the base of the flagellum. Since the secretory structure is made up of the same types of proteins as the base of the flagellum and is able to perform a function without having the other parts of the flagellum, it is believed that Behe’s contention that “any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional" is negated.
The creationist’s response is that the evolutionist is assuming that the proteins that make up the secretory mechanism are a precursor to the proteins that make up the flagellum. There is no evidence this is the case. The makeup of the secretory mechanism in no way negates the irreducible complexity of the flagellum. The fact that similar proteins are found in the secretory mechanism as those that make up the flagellum does not prove they are a precursor to those found in the flagellum. In every respect the secretory mechanism is its own irreducible complexity. To say that since the secretory mechanism has similar proteins to the flagellum and therefore the flagellum evolved from the secretory mechanism is to again introduce comparative anatomy as a determinative in how organisms have appeared. As discussed in part five of this series, similar anatomy does not show evolution but is a strong indicator of design.
REVIEW:
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.
THE DEVELOPMENT OF MAN:
Evolutionists postulate man has developed over the past million years from apes or a common ancestor to apes and man. In 1856, fossilized limb bones, a pelvis, ribs and a scull cap were found in the
Some Neanderthals had a brain size of around 1,740 cc as compared to 400 cc for apes and 1,350 cc for modern man. Other Neanderthals were found to have a brain size comparable to modern man. In 1908 a Neanderthal skeleton was found in
There has been much controversy in evolutionary circles as to Neanderthal and what role he played in the development of man. Some evolutionists have concluded that Neanderthal was not much different from modern man because the evidence shows his having ability to use fire, make tools, bury his dead and form culture.
In association with the quest to discover the origins of man, there have been a number of embarrassments in the field of paleontology which is the study of fossils. In 1922 a single molar tooth was found in
In 1912, an amateur archeologist found pieces of a cranium and a jaw along with remains of mammals and some stone and bone tools in a gravel pit at
There is the Peking Man, the Man of Heidelberg, Cro-Magnon Man, Java Man and a variety of other so-called hominids that have been offered as evidence for a gradual development to modern man (Homo sapiens). Many of these hominids were lumped together and called Homo erectus because they were believed to walk in an upright position. All these hominids have come about as a result of piecing together jaw fragments, parts of skulls, bones and other body parts. While various dating methods have been applied to determine the age of these body parts, as discussed in installment three of this series, such dating methods are problematic. For example, in 1951 a scull and jaw was found and named
ACCELERATOR MASS SPECTROMETRY:
In the late 1970s a new method of measuring carbon-14, called AMS, or Accelerator Mass Spectrometry dating, was developed. This involved directly counting the carbon-14 atoms, using a tandem accelerator. We discussed carbon-14 dating in installment two and three of this series. When using the AMS method, carbon atoms are first negatively charged. This eliminates most of the interference from nitrogen-14, which is much more common than carbon-14 but does not easily take a negative charge. In addition, each atom is accelerated by a very high voltage, and several tests can be done to make sure that we are in fact measuring carbon-14 instead of some interfering isobar, or cosmic rays. Theoretically, the machine should have zero machine background, which makes it ideal for attempting to detect carbon-14 in geologically old specimens.
The standard radiocarbon dating technique only attempts to count the disintegrations of carbon-14 atoms which are sometimes confused with other types of disintegrations. The AMS method only identifies and counts carbon-14. What is of much interest is that the AMS method has consistently detected at least some carbon-14 in every organic specimen tested, even materials formally tested and concluded to be millions of years old. Millions of years old materials would not have detectable carbon-14 still in them. In fact any organic specimen older than 70,000 years should have all their carbon-14 decayed. The fact that the AMS method has detected carbon-14 in every organic specimen it has tested indicates such specimens are much younger than previously believed.
According to a report in the book, “In the Beginning” by Walter Brown, page 245, eleven sets of human bones previously thought to be very old were dated at about 5000 radiocarbon years or less using the AMS method. Some believe that if more of supposed evolutionary ancestors of man are tested and are found to contain carbon-14, scientists will be forced to seriously consider that fossils of living organisms are not as old as previously thought. All research to date using AMS suggests that fossils are younger than previously thought.
SUMMARY:
Various questions come to mind as to the evolutionary approach to the development of man. If Homo erectus evolved from ape like animals, why did the brain size take such a sudden leap from apes to man? Creationists point out that the number of vertebrae in erectus is different from apes and, most significantly, the DNA of erectus and sapiens is distinctly different form apes, monkeys and all other wildlife. Another question is why written accounts of human activity don’s go back further than 6000 years if hominids/humans have existed for hundreds of thousands of years. Tools and other artifacts of ingenuity have been found with fossil remains of Homo erectus. His brain capacity appears to be equal and even superior to Homo sapiens. It would be logical to conclude that Homo erectus would have developed language and writing skills based on what is known about his IQ.
Careful investigation of Homo erectus has by and large shown them to have the same general characteristics as modern man. Characteristics that have been thought to be peculiar to erectus have been found to be present in modern man in various societies and cultures to this present day. This being the case, the designation Homo erectus as pertaining to ancestors of modern man or Homo sapien becomes irrelevant.
In essence, there appears to be only one species of man with a variety of genetic variations within that species. Assigning ancient dates to fossils of body parts identified as human is problematical for the reasons given earlier in this series. The new method of measuring carbon-14, called AMS, or Accelerator Mass Spectrometry may prove to be the Achilles heel of the proposition that life has evolved over millions of years. If AMS can validly show the age of fossils to be much younger than presently believed by evolutionists and some creationists, it should create a significant challenge to the current evolutionist paradigm that postulates fossils are millions of years old.