Jan's Bible Notes
EVOLUTION: FACT OR PHILOSOPHY?
by Jan Young
CHAPTER 6: THE BIOLOGICAL BASIS OF EVOLUTION
THE CASE FOR EVOLUTION
According to the theory of evolution, it is possible that the earth and our entire universe came into being through some natural process. It is even possible that life itself began naturalistically as a single-celled organism. How did that single cell somehow evolve into all the hundreds of thousands of life forms we see today?
According to Darwin's theory, all life forms are the result of random change, natural selection and mutations (genetic changes). Over vast periods of time, the accumulation of many small changes brought about large changes. Species changed into other, more complex, species. Each small change was maintained because it allowed the organism to better adapt to its environment.
For many years, scientists said that life evolved very slowly, one mutation at a time. But it now appears that the fossil record may not support that idea. Now many are saying that it happened more quickly. We will look into both of these ideas, as well as the concepts of natural selection, mutations, and other related aspects of biological evolution.
What is natural selection, and why is it so important to the theory of evolution? The process of natural selection can be summed up by the phrase, "the survival of the fittest."
Here's how it works. Organisms produce more offspring than can possibly survive in the world. Some of those offspring survive, and some don't. The ones that survive tend to have traits, or variations, that make them more likely to survive. Those who survive are described as being more "fit" than those who don't.
What is "fit"? Those who survive are "fit" because they will leave more offspring. Therefore, the more desirable traits are passed on, or "selected," and the less advantageous ones die out. Nature, rather than intelligent planning, does the selecting; hence the term, "natural selection."
As the environment changes, organisms either adapt to the changes or, if they cannot adapt, they die. The process of adaptation is what leads to natural selection. Natural selection is seldom actually witnessed because the changes are thought to be very small, and would take place over long periods of time. Evolutionists claim that the evidence can be found in the fossil record, although we have already seen that this claim is difficult to prove. Darwin's observations were based on the changes brought about in animals through artificial selection, where a human breeder selects certain traits.
As any biology book will tell you, the best example of natural selection that has actually been observed is the peppered moths of England. Around 1850, the peppered moths were mostly light-colored, so they were camouflaged when they landed on the light-colored, lichen-covered tree trunks. The dark ones were easily spotted by birds and eaten.
Then along came the Industrial Revolution, and the soot from factory smokestacks began to turn the trees darker. Pollution killed the light-colored lichen. The peppered moths evolved the ability to maintain their camouflage on the darkened trees by turning a darker color. By the 1950s, most of the moths were dark. The famous peppered moths are proof of evolution happening right before our eyes. This example is considered to be the showcase of evolution.
If evolutionary change is to take place in an organism, there must be some mechanism that can bring about change. What is this mechanism and how does it work?
Evolution happens by mutations. A mutation is a change in a gene or chromosome that is passed on to the offspring. Chromosomes are the carriers of genes, which are the units of heredity, and are composed of DNA. Genes and chromosomes are located in the nucleus of the cell. Darwin didn't know about genes or mutations; he was not aware of Gregor Mendel's famous experiment with peas and his discovery of the laws of heredity.
Later, Mendel's findings about genetics were applied to the theory of evolution. This modernized version of Darwinism is called "neo-Darwinism." Neo-Darwinism is the kind of evolution we have been discussing in this book, the traditional theory of slow gradual change by natural selection, mutations, and random change.
Because little was known at that time about heredity, Darwin believed that evolution involved the passing on of "acquired" characteristics to the offspring. In other words, if a giraffe continually stretched its neck out to eat leaves high on the trees, its neck might become a little bit longer, and its offspring would inherit its slightly longer neck. This is now known to be false. Genes, the units of heredity, are not affected by use or disuse. Genes are only changed by mutations.
Mutations occur randomly--that is, by chance, without rhyme or reason. 99.9% of all mutations are harmful or fatal to the organism. So how could mutations bring about positive changes? Over a very long period of time, a few positive mutations will occur. Because a good mutation gives greater survival value, it will allow the organism to better adapt to its environment. Natural selection will see to it that these positive mutations are passed on to the offspring.
Slowly and gradually, over very long periods of time, good mutations will occur and accumulate in the population. Each small change will provide greater adaptation. Natural selection will ensure that positive changes continue to accumulate and negative ones will die out. Organisms will gradually grow more and more complex. One species will gradually develop into another species, and that one will change into another more complex one. Eventually, we end up with the great diversity of life that exists today.
BIOLOGICAL PROOFS FOR EVOLUTION
Evolution takes place by means of natural selection, mutations, random change and vast periods of time. We have looked at geologic proof for evolution from the fossil record and from radioactive dating techniques. Now let's look at some of the biological proofs for evolution.
The most obvious evidence for evolution is the fact that many organisms have similar features. This similarity is called homology (hom = same; logos = to speak). According to most scientists, the only possible explanation for this phenomena is an evolutionary relationship. Because most creatures share certain characteristics, like eyes, limbs, digestive systems, and respiration, we know they must have descended from a common ancestor.
If they didn't descend from a common ancestor, how could so many organisms have characteristics that appear to be so similar? Those features couldn't have evolved independently many different times. It is obvious that the human arm resembles the wing of a bat or bird, the foreleg of a horse or dog, and the fin of a fish. These related limbs all carry out a similar function. Similarities are the basis for classifying different kinds of organisms.
Another important proof for evolution is the study of the embryos of different kinds of organisms. This is called embryology. The developing embryos of humans and other higher animals appear to retrace their evolutionary past. This is evidence of their common ancestry. As they grow, embryos pass through an evolutionary sequence that is inherited from their common ancestor. For example, the developing human embryo displays gill slits, which is evidence of our fish ancestors. As the embryos develop, they become more dissimilar. The DNA that controls their later development reflects the mutations that have brought about the different stages of life.
The existence of vestigial organs is another proof that evolution has taken place, and is indeed taking place now. A vestigial organ is a body part that once had a useful function, but is now a useless "vestige" of an earlier time. The appendix is a vestigial organ, as well as the tailbone and the muscles that move the ear.
The newest field of scientific proof is that of molecular biology. Chemical tests have established that organisms share biochemical similarities. The closer the similarity of various organisms, the closer the evolutionary relationship. If all organisms were not related, but had somehow arisen independently of each other, it is unlikely that they would share the same biochemical makeup.
Any discussion of evolution centers around the concept of species--change within species, change from one species to another, how different species fit into the pattern of evolutionary descent. What is a species?
The definition of a species is not clear-cut, nor is there agreement among biologists as to what exactly constitutes a species, or how species should be labeled. Species are the lowest level of biological classification. A group of related species make up a genus, a group of genera (plural of genus) make up a family, a group of related families make up an order, a group of related orders make a class, and related classes make up a phylum. Phyla (plural of phylum) are the basic divisions of the two kingdoms--plant and animal. This is the way biologists classify all life forms.
Even though species are the lowest formal classification, there are other terms used to label smaller groups within a species, such as varieties, races, subspecies, and some others. None of these groups are clearly defined either. One possible definition of species is a group of organisms that have certain characteristics, that breed among themselves but not with other groups, and that pass on their characteristics to their offspring. But not all biologists would agree that this is true in every case, or that there even is such an entity as a species; it may be just a convenient label.
Darwin's voyage to the Galapagos Islands, on board the Beagle, played a major role in the development of his theory about the evolution of species. On the island lived fourteen species of finches, now known as "Darwin's finches." Although they were obviously all closely related, they differed in color, beak shape, size and feeding habits. It seemed clear to Darwin that the finches were all descended from a common ancestor, and that therefore, species were not "fixed," but could evolve into other forms.
While it is true that there is evidence for the evolution of one species from another species, no one has ever directly observed such an event, according to biologist Michael Denton. Neither has evolution been observed to occur at a level above that of species. However, the theory of evolution is based on the logical assumption that if changes can occur at the species level, those changes must accumulate and eventually, over many millions of years, bring about change at higher levels also.
The traditional view of evolution has been that of gradualism--slow gradual change over long periods of time. Mutations are rare occurrences, and positive ones are even rarer. Evolutionary change happens slowly, one mutation at a time, with each change being perpetuated because it gives the organism greater survival value.
Studies of the fossil record have cast some doubt on this view. Although many still claim that the fossil record does support gradualism, others admit that life forms appear in the fossil record suddenly, fully formed, and are then characterized by stasis--little or no change. If gradualism were true, the fossil record should be chock-full of transitional forms, showing the pattern of one form blending into another by minute changes.
If gradualism is false, then there must be another explanation of how evolution works, one that fits the fossil record. If evolution did not happen slowly, it must have happened rapidly. It must have happened too quickly to leave its mark in the fossil record. Most dead organisms did not become fossils, only those few that happened to be in an unusual situation that would cause them to be quickly buried. So if organisms were evolving rapidly, it is highly likely that most of them would not be fossilized; hence, the lack of transitional forms in the fossil record.
Yet the fossil record also shows stasis, so rapid evolution couldn't be happening constantly; from time to time, new forms must have appeared suddenly. Recently, Niles Eldridge and Stephen Jay Gould set forth a theory called punctuated equilibrium: long periods of equilibrium (stasis, no change) punctuated by short episodes of rapid change. Although it has been widely publicized, not all evolutionists accept this theory.
At present, the only two views of evolutionary change are gradualism and punctuated equilibrium. However, most scientists are firmly convinced that, regardless of how it happened, evolution is without a doubt the only possible explanation for the origin of the organisms that inhabit our world today.
PROBLEMS WITH EVOLUTION
Surely natural selection, acting on mutations, over millions and billions of years, could bring about almost any possible change. If given enough time, it is often said, the odds are that just about anything could happen. How else can we account for the similarities that we observe in organisms?
But can these things take place? How does natural selection change one species into another? How do mutations work? How much change is possible in several billion years? How similar are the different forms of life?
1. Defining Evolution
What does the word "evolution" mean?
The word itself has a wide range of meanings. A quick check of the dictionary shows that it can mean just "the process of change"--a very broad definition.
It can also mean "a series of related changes"--more specific, but still quite broad. This meaning of the word--change in general--can be applied not only to biology, but to many subjects, such as society, or the automobile, or even to a specific make of automobile.
"Evolution" is also defined as "the theory that all living things developed from a common ancestor." It is often equated with the term "Darwinism." Now we have a much more specific definition. It narrows the subject down to what we refer to in this book as "the theory of evolution." How can you know which definition scientists mean when they use this word--the broad, or the narrow? This is one of the big problems with evolution. Sometimes you can't tell. And it makes a very big difference.
Does evolution mean "change"? Yes, but what kind, and how much? In the broad sense--change in general--everyone agrees that evolution takes place. It is impossible to deny. But in the narrow sense--Darwinian change--evolution is still debatable.
The claim that "evolution is a fact" is misleading, because it is sometimes difficult to determine what is really being said. Which kind of evolution is a fact? As we have already seen, redefining or blurring of terms is popular among evolutionists. If the term "evolution" can mean virtually any kind of change, small or large, who can argue that it happened?
Two terms that help define the word are "microevolution" and "macroevolution." Microevolution means small changes--changes within types. Macroevolution means major changes--changes from one type to another. Microevolution is commonly referred to as adaptation or variation. Genes have a built-in capacity for variation. This is what allows organisms to adapt to their environments.
The term “adaptation” is often used synonymously with evolution. Those who observe adaptation like to claim that we are seeing evolution in action. And because adaptation can take place rapidly, people are claiming that today evolution is taking place faster than ever. One example is the book The Beak of the Finch: A Story of Evolution in Our Time, by Jonathan Weiner.
Another example was an April 24, 1996 report on “ABC World News Tonight” with Peter Jennings. Studies of wildlife around the site of the nuclear accident at Chernobyl in the Soviet Union show that, despite the heavy dose of radiation, mice were surviving and adapting. Scientists were excited that evolution was proceeding at much higher rates in the last few years than in all the previous millions of years. However, the next day’s installment of the report lamented the effect on the residents still in the area. Evolution is always presented as change for the better. Yet when humans are exposed to possible genetic mutations, no one gets very excited about the possibilities for the future.
The theory of evolution requires macroevolution to take place. It is based on the concept that since we know microevolution takes place, then it must logically follow that many small changes added together have resulted in macroevolution.
This type of logic is called extrapolating. If one thing is true, and you carry it out over any given period of time, it must continue to be true. It must continue to happen in just the same way. We have already seen that extrapolation is not always a very scientific procedure. Can you really extrapolate from microevolution to macroevolution? Is there any scientific evidence for such extrapolation?
Many systems contain built-in limits beyond which change cannot take place. Artificial breeding experiments with animals show that there is a limit to the kind of change that can be induced, beyond which you cannot go. Dogs and horses can be bred for size, but does that mean that we can eventually breed a horse that is larger than an elephant or a dog as small as a pencil eraser? A certain amount of variation is genetically built in to all organisms, but not an unlimited amount.
If change beyond a certain point cannot be brought about by human engineering, how likely is it that it could happen by the undirected process of random change? The theory of evolution requires that this did happen, by random change, mutations, and natural selection.
However, there are no known examples of macroevolution, not even in the fossil record. Many books on evolution give examples of evolutionary change, but they are all examples of microevolution. This is not what is needed for evolution to take place. As Denton points out,
"...it does not necessarily follow that, because a certain degree of evolution has been shown to occur, therefore any degree of evolution is possible. There is obviously an enormous difference between the evolution of a colour change in a moth's wing and the evolution of an organ like the human brain..."
Yes, evolutionary change within types is a fact. Everyone can agree with that statement. But from "fish to philosopher?" Is that kind of evolution a fact? You are not being unscientific by disagreeing with that kind of evolution, at least not until there is more evidence to support it.
If someone wants to know if you believe in evolution, ask: "Microevolution or macroevolution?" If they don't know what you mean by that, then an explanation of the difference is a good place to begin the discussion.
2. Natural Selection
Is natural selection the process by which evolution has taken place?
Natural selection means "survival of the fittest." The fittest are those who leave the most offspring. What does this tell us about how one kind of organism can change into another kind? Nothing. Yet evolutionists use the phrase "survival of the fittest" as if it proves the theory of evolution.
If the fittest are those who survive and reproduce, then all that has really been said is, "the survival of those who survive." This is merely playing games with words. There is even a name for this kind of word game. It is a called a "tautology" (tah-TALL-uh-gee)--a way of saying the same thing twice, or defining a word by the word itself.
It is like saying "an expert who is experienced in his field," or "an old antique." If a student handed in a paper with such a redundant statement, any teacher would red-line it.
If scientists recognize that survival of the fittest is a useless concept, why do they continue to rely on it? Norman Macbeth points out that they don't.
"The biologists have discarded survival of the fittest, together with the words fit and fitness in their normal usage, and they have been perfectly open about this."
However, the general public "have noticed nothing. They continue to talk of fitness in the old way and to regard survival of the fittest as sound doctrine." He draws attention to the "vast gulf" that exists between what evolutionists say among themselves and what they allow the public to believe.
Is natural selection really the backbone of the theory of evolution? The concept of natural selection was first published by Edward Blyth, a non-evolutionist, 24 years before Darwin's Origin of Species. Anyone can agree with natural selection whether or not he agrees with evolution. Natural selection is not a synonym for evolution. The concept itself does not imply evolution. It did not make any great waves until it was applied to the theory of evolution.
When Darwin offered natural selection as the mechanism for evolutionary change, he lacked examples to point to. Instead, he used examples of artificial selection--controlled breeding experiments. He tried to draw an analogy between artificial and natural selection although the two processes are not at all the same. Random change and directed change are not equivalent processes.
In artificial selection, breeders "select" for certain traits, bringing about greater variety within the species. Greater extremes are created. In natural selection, extremes are weeded out by the selecting process. Natural selection tends to discourage change, rather than bring about greater change. In fact, the extremes brought about through artificial selection disappear when domesticated animals are returned to a natural state. They quickly revert to the original type.
When a dog breeder selectively breeds for a certain trait in a dog, he does bring about or help establish a certain amount of change. He always gets an animal that is definitely a dog. No dog breeder has ever come up with an animal that is not quite a dog, or appears to be "on the way" to some other new species.
No new species has ever been brought about by artificial selection. But even if one were created, it still would not prove that change above the species level is also possible. Artificial selection is evidence against natural selection, not for it.
Natural selection acts only upon existing traits. It cannot create new traits or greater complexity. The changes, or variations, that it seems to bring about are only variations that are already present in the genetic make-up. Natural selection cannot cause the formation of new genes, which would be necessary in order to bring about new, more complex traits.
Natural selection acts in favor of stasis, not change. "Living fossils" are evidence for stasis. Why have they persisted unchanged throughout millions of years? Why has natural selection not been acting upon these creatures? It has; it has been acting to weed out extreme variations and to maintain the basic type. This is what natural selection does.
The peppered moths of England are featured in virtually every biology book as natural selection in action. They are held up as proof of evolution. However, it is very important to make a distinction between natural selection and evolution. Natural selection is not evolution.
The color change in the peppered moths is not evidence for the origin of a new species. It is not even evidence for a new variety within a species. Both light and dark moths already existed. All that changed was the ratio of dark moths to light moths. Before the observed color change, the species was Biston betularia. Afterwards, the species was still Biston betularia.
Darwin's finches are also used as a proof for evolution. Yet despite minor variations in certain traits, they are all definitely finches. There is no evidence here for the idea that one kind of creature can change into another. All we see is evidence for the built-in capacity for variation that enables every organism to adapt to its environment. We do not see natural selection leading to macroevolution.
Although mutations were unknown to Darwin, they are essential to the modern version of the theory of evolution (neo-Darwinism). Mutations are the agent, the raw material, of evolutionary change. Mutations act on the genes to bring about slow, gradual change, one gene at a time.
Each change is maintained because it provides the organism with greater complexity and greater adaptability to its environment. The mutation is perpetuated by natural selection. The organism with a beneficial mutation should be more likely to survive and leave offspring. The offspring will carry the mutated gene and will thus inherit the same beneficial trait.
This is what is supposed to have happened. But is this possible? Is there any scientific evidence that this has happened, or could happen? Let's look at what is known about mutations.
To begin with, mutations are rare. When they do occur, 99.9% of them are harmful or fatal to the organism. The only mutations that can further the process of evolution are positive mutations, or just one-tenth of one percent of all mutations.
Over a long period of time, a positive mutation will occur. But many destructive mutations will have occurred in that same period of time. The negative effect on the population will greatly outweigh the effect of the positive mutation, if that positive mutation is even able to establish itself as a permanent trait.
How likely is it that one positive mutation could bring about a change with greater survival value? In order to bring about a new trait, Morris and Parker calculate that numerous related mutations must happen simultaneously. What are the mathematical chances of two related positive mutations happening at the same time? Only one in 10 to the 14th power (that is, 10 with 14 zeroes after it). Of three related changes? One in 10 to the 21-power. How about four? One in 10 to the 28-power. Probably many more changes than that would be required to occur simultaneously to bring about a new trait.
Consider how many changes would be needed at once to bring about the eye by the process of mutations. What would one single mutation accomplish? Why would any single mutation be maintained, since none of them would have any greater survival value until the eye was completely functioning? Darwin admitted that for natural selection to have created the eye, each stage, each tiny change, would have had to provide greater survival value. Along with the complete eye would be needed the nerve and brain capacity to make use of it.
"To suppose that the eye with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest degree." (The Origin of Species)
Not only is the evolution of the eye by mutations extremely unlikely, but because of the many different kinds of eyes, the eye must have evolved independently many different times--an unlikely coincidence. Primitive types of eyes still persist today in many creatures. Why haven't they evolved into more complex eyes by now? And complex eyes, in trilobites, appeared in the earliest strata containing multi-celled organisms.
Imagine other body parts besides the eye changing slowly, one mutation at a time--a gill to a lung, a fin to a leg, a foreleg to a wing. If a mutation occurred in a gill, which was already complete and fully functioning, it would no longer be a normal gill. A complete, normal gill already functions perfectly. A change that makes it less gill-like and more lung-like would not improve the gill's level of function. On the contrary, it would probably be less able to function properly than a complete, normal gill.
What improved level of function lies between a gill and a lung? Can we logically assume that a half-gill-half-lung would be more advantageous than a normal gill? Would it work better than a normal gill? Until it had evolved into a fully functioning lung, the poor fish would be more likely to drown.
Would such a fish be more "fit" than its neighbors? Would it have greater survival value? If such a mutation occurred, it does not seem likely that it would be favored by natural selection. It seems more likely that natural selection would weed out such a mutation in favor of a normal, complete gill.
Imagine the same predicament from fin to wing. Without a change in accompanying bone structure, nerves, blood vessels, and muscles, how could a creature benefit from only one mutation in the direction of change? No wonder creatures that are born with some mutation are called "monsters." They are either unable to survive, or less likely to thrive. They are at a disadvantage, not an advantage.
Can mutations bring about greater complexity? Evolutionists say "yes." If the answer is yes, then mutations must be capable of producing new genes. For an organism to increase in complexity, new genetic material must be added. Otherwise, we would have to assume that the first single-celled organism already contained all the genetic material needed to generate every single form of plant and animal life, including humans. If it was genetically programmed for a human being, why would it reproduce offspring that were only single-celled?
However, a mutation is the recombination of existing genetic material or the loss of a gene. It is not possible to gain new genes. Mutations do not produce new genes. Yet this impossible phenomenon happened if evolution is true. It happened not once, but billions of times.
Consider the example of bacteria that have supposedly evolved resistance to antibiotics--another common "proof" of evolution in action. Did mutations bring about this ability? No. We know this because the resistance to antibiotics was present in the bacteria even before antibiotics were invented.
Studies on bacteria that were frozen in 1946 before the advent of antibiotics showed that some of those bacteria were resistant to at least six different antibiotics. Carl Wieland reports that bacteria from the intestines of three explorers who froze to death in the Arctic in 1845 were studied. These bacteria were also found to be resistant to modern-day antibiotics.
Wieland points out that the capacity for resisting certain substances is already built-in. Most resistance is the result of processes that are not related to mutations. If mutations are a factor, it is generally because certain genes have been lost. In other words, no new information has been added. Variation is somehow built into the genetic design of the organism.
Another example is an experiment with aquatic worms by Professor J. Levinton of State University of New York, as reported in Creation (March-May 1994). In his experiment, resistance to a toxic substance developed in only three generations. Those worms that did not die from the toxin already had the genetic ability to adapt. No new genetic material was added to them.
But Dr. Levinton saw his experiment as evidence of evolution, and wondered, since evolution can happen that fast, why evolution has not produced any new body plans in the past 500 million years. That's a good question. If the change he observed was indeed evolution in action, then we should see much evidence of radical change in the fossil record. But we don't.
If mutations are the agent of evolutionary progress, why is it that no doctor or parent in the delivery room prays for a mutation? If mutations are the agent of evolutionary progress, then why the current concern for the destruction of the ozone layer? Its destruction would only lead to a greater chance of mutations, and therefore further the progress of evolution, wouldn't it? No. It would increase the rate of skin cancer, which is negative change, not positive.
If mutations are the agent of evolutionary progress, then why do people avoid marrying close relatives? If intermarriage increases the chances of mutations, it would speed up the process of evolution, which would be good for the human race--wouldn't it? Of course not. Even though marrying close relatives can increase the odds of a good mutation, the chances of increasing the odds for a bad mutation are much, much higher. Early in human history, this would not have been a problem, because mutations would not have had enough time to accumulate in the genes. However, as more and more generations reproduce, mutations which were once "recessive," or less likely to appear, tend to build up and become more likely to appear.
4. Punctuated Equilibrium
After breeding and studying gypsy moths for twenty years, geneticist Dr. Richard Goldschmidt realized that all he had been able to cause was microevolution. But the theory of evolution required macroevolution.
In 1940, he wrote that what must have happened was not the accumulation of slow gradual changes, but some sort of mutation (every now and then) that produced a completely new kind of creature. This creature would be capable of life and would be an improvement over existing life forms. This hypothetical creature became known as a "hopeful monster."
Let's say that such a thing could happen. Where would such a creature find a mate? Could this mathematically impossible event happen twice? making one male and one female? at just the same time? in the same "neighborhood," so that they could find each other? so that both could just happen to survive long enough to mature, meet, mate, and successfully reproduce?
The challenge to the imagination is great. It would be easier to believe in miracles. Yet evolution is all about doing away with miracles and explaining life in terms of natural, normal processes.
Many evolutionists found "hopeful monsters" impossible to accept, too. Based on what was known about genetics and mutations, they were just too improbable. But the idea would not die. It continued to surface in the writings of evolutionists, and in 1958 a children's book, The Wonderful Egg, was published that told the story of how the first bird hatched out of an egg laid by a mother dinosaur.
Scientists had a dilemma. It was becoming obvious to more and more of them that slow, gradual evolution, one mutation at a time, could not have happened. The fossils seemed to indicate that it did not happen. On the other hand, the hopeful monster was just too monstrous to solve their problem. A better mechanism for evolution was needed.
In the 1970s, Gould and Eldridge found a way to improve the unpopular image of the "hopeless" monster with their theory, punctuated equilibrium. They claimed that, occasionally, small changes that took place while the embryo was still developing would result in a major change to the adult organism. The changes were remarkably along the lines of a hopeful monster. This theory represents a major break with classical Darwinian evolution, which denies the possibility of change by large "jumps."
Is there fossil evidence for this new theory? According to a concept called "population genetics," these mutations must have taken place in small isolated populations, which allowed the new forms to change and spread so rapidly that they weren't around long enough to show up as fossils. After a new species formed in this small group, the small group reunited with the main population and the new species became established. Lacking fossil evidence, we again have an argument from silence.
5. Random Change
If natural selection and mutations were responsible for evolution, they must have operated at random. There was no logical plan or set of instructions guiding these processes. There was no one to choose which trait would be "selected" or which gene to mutate. "Random change" is change that came about through trial and error.
Probably most of you reading this book have used computers. If you brought up the screen with your computer's main setup--the directions for how the computer starts up and uses the software that has been installed--what do you think would happen if you changed one randomly-chosen symbol on that screen? How likely is it that you would have caused anything to work better than it already does? On the other hand, it is extremely likely that something wouldn't work right, or wouldn't work at all.
The concept of random change has been thoroughly tested on computers. According to Denton, all computerized versions of evolution have failed. Trial and error is unable to bring about any positive change in computer programs.
This is not hard to believe. Try applying the random change method to something much less complex than a computer. How about your watch? Choose any part, and change it. Make it bigger, or smaller, or a different shape; put it in a different place, or just leave it out. How likely is it that your watch will run better?
Randomly change one letter in a sentence and see if it makes more sense. How many such random changes would you have to try before the sentence makes better sense? Or randomly change any word on a page. How many tries would it take to improve the sense of what was already written?
New information does not happen by itself. It can only arise by intelligent direction. How did DNA form? It could not be the product of random chance.
You may wonder: given a long enough period of time, isn’t anything possible? That's a popular idea, but not necessarily true.
"The Darwinian claim that all the adaptive design of nature has resulted from a random search, a mechanism unable to find the best solution in a game of checkers, is one of the most daring claims in the history of science. But it is also one of the least substantiated. No evolutionary biologist has ever produced any quantitive proof that the designs of nature are in fact within the reach of chance." (Denton)
Homologous (hum-ALL-uh-gus) structures, or similar structures, are claimed to be major evidence of common ancestry. For example, a wing, a fin, a foreleg and an arm are referred to as homologous. They develop from groups of cells in the embryos that have a certain amount of similarity. They have roughly similar bone structure and perform roughly similar functions.
However, homology is based on weak similarities. If homologous structures were actually proof of evolution from a common ancestor, they should develop from the same kinds of genes. Instead, they often develop from completely unrelated genes. This is seldom mentioned in biology books.
When the evolutionist points to the similarity of a fin and a foreleg, he concludes that the foreleg evolved from the fin. Why did some fins evolve into limbs but not others? If limbs evolved from fins, we should have a dorsal limb--a limb in the middle of our backs. The argument from similarity is not consistent.
If homologous structures indicate common ancestry, what about “analogous” structures--similar structures in organisms that are so dissimilar that they could not possibly have descended from a common ancestor? There is no explanation for this problem, but it is given a scientific-sounding name--”convergence.”
Whales resemble fish outwardly, but resemble mammals internally. Whales and fish are so different that they can't possibly have a common ancestor. The eyes of vertebrates and cephalopods have similar design, but these creatures can't possibly have a common ancestor. The wings of birds and bats share some similarities, but do not reflect common ancestry.
The duck-billed platypus lays eggs, builds a grass nest, has a bill and webbed feet. Is it a bird? It also has fur, four legs, nurses its young, and has a mammal-like tail and claws. Is it a mammal? Did it evolve from a bird or a mammal?
Convergence contradicts the concept of homology. According to the theory of evolution, similar structures in similar organisms prove common ancestry. But if similar structures are found in organisms that are completely different, then they don't prove common ancestry. Is similarity proof of common ancestry, or isn't it?
There is also the problem of “divergence”--the occurrence of dissimilar structures in similar organisms. If similar structures in similar organisms can be used as proof of evolution from a common ancestor, why aren't dissimilar structures in similar organisms considered proof of no evolution from a common ancestor? It is just as logical a conclusion.
If all similar structures fit the pattern of descent from a common ancestor, the argument would be fairly believable. But how scientific is it to pick which similar structures are evidence for evolution, and virtually ignore the rest? Is it scientific to select which evidence will be considered and which evidence will be ignored?
Homology creates as many problems as it supposedly solves. Take the classification of mammals. Whales are mammals, but because mammals are land creatures, and are said to have descended from marine creatures, whales must have descended from some type of land mammal and then evolved back into a water-dweller. Today scientists are busy looking for a way to prove that whales once had legs, plus all the other adaptations for living on land.
A recent fossil find in Pakistan, reported in two articles in Science (14 January 1994), is claimed to be some sort of walking whale, perhaps one of the missing links in the land-mammal-to-water-mammal evolution. The article by Berta concludes that the find is significant "in documenting the locomotory transition in whales from land to the sea." The other, by Thewissen, Hussain and Arif, makes an even stronger claim:
"As such, Ambulocetus represents a critical intermediate between land mammals and marine cetaceans."
But how compelling is the evidence for such a claim? The fossil skeleton is incomplete, missing some very important parts. True whales have been found in the same strata as this skeleton, according to Creation Ex Nihilo Technical Journal (Vol. 8/1, 1994), so how could it be an ancestor to the whale? If it were an ancestor, it should have been found in strata lower than the strata containing true whales.
As scientists dig deeper into the molecular makeup of life, it becomes increasingly evident that homology cannot explain either the similarities or the differences in organisms. Although still presented as a strong argument for evolution, homology is inconclusive.
Embryology is based on the belief that the developing human embryo relives its evolutionary history. Certain structures of the embryo appear, at various times, to have characteristics of our evolutionary "ancestors," such as gill slits (like a fish), a tail (like a reptile), and a yolk sac (like a chicken). The human heart is said to go through various evolutionary stages: worm, fish, frog and reptile. Then it enters its human stage. This theory is also frequently referred to as the "biogenetic law" or as the theory of "recapitulation" (recapitulate: to repeat).
The most popular evidence for the theory has to do with gill slits. These are grooves and pouches in the throat area of the human embryo that visually resemble a fish's gills. However, they have nothing to do with gills or even with any breathing process. They will develop into glands and the middle ear canals. They are not gills, they are not slits, and they are not evidence of a fish ancestor.
What about the tail? Humans do have what is commonly referred to as a tail bone, although it has nothing to do with a tail. In the embryo, it superficially resembles a tail. It sticks out like a tail because the muscles that cover it have not yet developed. It is merely the coccyx--the end of the spine. It has nothing to do with evolutionary ancestors; on the contrary, it is extremely important for our uniquely human upright posture. It is necessary for muscle attachment and for proper functioning of the excretory system.
The yolk sac is a structure outside the embryo that provides the first blood cells needed by the embryo. Just because it is similar to a structure of the chicken's embryo does not prove that the chicken is our ancestor. As in homology, similar structures are often found in different organisms.
None of these are throw-backs to evolutionary ancestors, nor are they mistakes in DNA, as some claim. Each structure is necessary for man's unique physical development.
Every creature is born with DNA that will form the same kind of creature that its parents were. DNA is programmed exactly for one kind of life. It produces creatures that reproduce after their own kind. Humans can't have gills because our DNA is human. It is never part fish or part reptile. Humans are 100% human from the moment of conception. The idea that a fetus isn’t human in its early stages is false.
Ernst Haeckel is credited with popularizing the theory in the 1800s. But the drawings he made of embryos were fraudulent. He not only admitted that he falsified his drawings; he was convicted of forgery, and the entire incident was publicized in 1911 in a book called Haeckel's Frauds and Forgeries.
The theory he popularized continued to be accepted by many scientists for decades, and a few continue to cling to it even today. Most leading evolutionists admit that recapitulation is completely discredited, and has been since 1921, following the publication of a paper by Professor Walter Garstang. Yet it is still frequently mentioned in current high school and college textbooks.
8. Vestigial Organs
Humans and animals have certain organs and other structures that don't appear to have any useful function. Evolutionists call these vestigial organs because they think they are "vestiges" (leftovers) of earlier evolutionary stages of life. As with homology and embryology, this belief is based on superficial outward appearances. The list of vestigial organs has steadily decreased as our knowledge of anatomy has improved. Textbooks published in the 1960s listed around 200 vestigial organs in man. Now we know at least some of the functions of virtually all vestigial organs.
The idea of evolution gradually ridding us of body parts that are no longer needed is genetically false. At one time (back in Darwin's day) people thought that acquired characteristics could be passed on to offspring. For example, if a giraffe continually stretched to reach high branches, his neck might become a little longer, and his offspring would inherit a slightly longer neck. The idea of "acquired characteristics" was disproved in the 1800s. Yet the concept of vestigial organs depends on the same disproven assumptions--that use or disuse affects heredity. Now we know that genes control the formation of the body, and genes are not affected by use or disuse.
If evolution is true, and if vestigial organs are evidence of evolution, then we should also see new organs and structures forming. If unneeded structures are in the process of disappearing, then it is just as logical to expect new, evolving structures to be appearing. However, our bodies have no such partly formed, evolving new structures.
What are some of the so-called "vestigial" organs? Here are a few, along with some of their known uses: 1) Wisdom teeth, or molars--for grinding food. 2) Tonsil--part of the lymphatic system; destroys bacteria. 3) Appendix--part of the lymphatic system; regulates intestinal immunity. 4) Tail bone, or coccyx--needed for attachment of muscles necessary for upright posture, elimination, and childbirth. 5) Thymus--part of the lymphatic system; produces lymphocytes in children, which are white blood cells that fight bacteria and viruses. 6) Thyroid gland--produces hormones that regulate growth and development. 7) Pineal gland--secretes a hormone called melatonin; helps regulate our biological clocks. 8) Ear muscles--for gathering sound; for facial expression. 9) The fold of tissue in the corner of the eye called the semi-lunar membrane--supports the eyeball and the tearduct; collects foreign matter.
Because man has not yet discovered how or why something works does not prove that it is useless. The shrinking list of vestigial organs shows that as our knowledge increases, the concept itself is merely a vestige of an earlier era.
"Nevertheless, we ought, in the first place, to be extremely cautious in pretending to decide what structures now are, or have formerly been, of use to each species." (Charles Darwin)
9. Molecular Biology
Since the 1950s, advances in the field of biology have been drastically transformed by the study of molecular biology, the study of the actual makeup of the molecules that form the cells. We now know about such things as the protein molecule, which can't even be seen unless it is magnified a million times. We know about the two very important nucleic acids--the DNA and RNA molecules.
Before the "molecular revolution," it was only possible to compare organisms based on visual similarities. Now they can be compared on the basis of their chemical compounds. What light has all this new information shed on the theory of evolution?
Biologists tell us that closely related species will have chemical compounds that closely resemble each other. "Closely related species" means organisms who closely resemble each other, as in homology. The assumption is that resemblance proves common ancestry, yet the only reason to assume this is a prior belief in common ancestry. This is another instance of circular reasoning.
As in homology, only a few limited comparisons can be successfully used to promote evolution. Other comparisons contradict those few. If you examine all the different chemical properties that can be compared, there is no overall similarity, no trend toward evolutionary progress. If evolution is true, and chemical resemblance is proof of relationship, then all tests should validate the theory. They should line up in the same evolutionary chain of descent that outward similarities suggest. This is not the case.
The study of homology on the molecular level is based on the assumption that all life is related because all organisms share certain characteristics, like DNA, RNA, and a protein called "cytochrome c." Trying to establish evolutionary relationships by homology has led to chemical tests on these and various other substances. Molecular biology provides no evidence for the theory of descent from a common ancestor, according to molecular biologist Michael Denton.
What it does show is that every type of organism is distinct and separate. Even organisms that "look" similar, based on outward appearances, show no similarities at the molecular level. Transitional groups are completely missing. Denton says,
"...none of the groups traditionally cited by evolutionary biologists as intermediate gives even the slightest hint of a supposedly transitional character."
Another molecular biologist, Michael Behe, claims in his book Darwin’s Black Box, “Molecular evolution is not based on scientific authority.” He goes so far as to say that it is “merely bluster.”
Behe has studied molecular systems that are “irreducibly complex.” That term describes systems in which several parts work together, and which can’t work if any one of those parts is missing. Such interrelated systems in the cell could not possibly have evolved in a step-by-step process. All the parts must be present at once in order to function.
No scientist has ever published a description of how such evolution could have happened. Behe finds this lack of scientific support to be an indication that the evolution model is not even credible at the molecular level. Behe’s charges against the evolution-based scientific community are grave. Unlike many other critics of evolution, he is being taken quite seriously. This is an unusual development in the field of evolution.
Another concept we are hearing about from the field of molecular biology is the "molecular clock." This is supposed to explain why there is such molecular "distance" between all groups of organisms. Denton claims it is no explanation at all, merely another tautology.
"This new era of comparative biology illustrates just how erroneous is the assumption that advances in biological knowledge are continually confirming the traditional evolutionary story. There is no avoiding the serious nature of the challenge to the whole evolutionary framework implicit in these findings."
Molecular biology has shown that each type is separate, distinct, and clearly distant from all others. If this is so, concludes Denton, "then the whole concept of evolution collapses."
10. Biological Mysteries
If life is the result of evolution, there are many unanswered questions that can't be explained by natural processes. The origin of such unique creatures as the bombardier beetle and the ant-lion is hard to explain by evolutionary processes. There are many examples in nature of mutualism, or symbiosis--two organisms that have a mutually beneficial relationship.
How could one organism gradually develop behavior based on another organism's behavior, while at the same time, the other organism is also gradually developing behavior based on the first organism's behavior? Darwin, recognizing the problem of mutualism, comments:
"Natural selection cannot possibly produce any modification in a species exclusively for the good of another species..."
Can instinct be explained by evolution? Instinct is unlearned knowledge that is present right from birth. How did animals survive before their instinct was completely developed? Instinct could not have evolved. Unless it is perfect, it is useless. Partially developed instinct gives no greater survival value; it gives less, since without it an animal would die.
Mammals are born with the sucking instinct. How did they survive while it was partly developed, or just beginning to evolve? How did birds evolve the instinct to build nests, and why are some fancy and some plain? Why did some birds not evolve the nest-building instinct? How did spiders evolve the instinct to spin certain designs in their webs? How did bees evolve the ability to communicate direction and distance so other bees could locate the food source?
Why would the bee evolve a stinger as a weapon? How could it give greater survival value if its use resulted in the death of the bee? How could the bird’s egg evolve? How could bone evolve from creatures that had no shell or skeleton? There would be no need for it until vertebrates had evolved. Yet vertebrates could not evolve without bone.
The migration of birds and other animals is another mystery that evolution can't explain. Many birds travel thousands of miles, some on a journey they have never been on before. Birds have a built-in calendar, clock, and the ability to tell latitude and longitude. They can tell direction by the stars. How does their instinct guide them? How could this evolve? What happened before it evolved completely?
How could random change result in the unusual and complex life cycle of the monarch butterfly? Why, in the caterpillar's pupa stage, would the inside of the pupa, or chrysalis, turn to liquid? What survival benefit would this give the monarch? Why would it shed its head capsule, including its six eye lenses? What evolutionary process could cause the pupa liquid to somehow turn into a butterfly of magnificent beauty? How could this liquid form two compound eyes with 6000 lenses each?
How would evolution give a butterfly the ability to migrate thousands of miles to its winter home? Some monarchs fly from Canada to Mexico. They do not always return to their northern homes in one generation. For example, some monarchs only return as far as Texas, where they lay their eggs. The next generation travels farther north, and sometimes the fifth generation will finally reach the northern destination. How can a multi-generational instinct evolve?
11. Complexity vs. Simplicity
Evolutionists have always assumed that natural selection selects in favor of greater complexity. Research has shown that this is not so. Compared to their ancestors, descendants are just as likely to be less complex as more complex.
But the problem of complexity is more complex than that. Biologists classify traits and organisms according to how simple or complex they are. They have decided what is complex and what is simple, based on appearances. Are these distinctions legitimate?
In considering what is the simplest form of life, we saw that simple things are very complex. Perhaps our ranking of simple-to-complex is completely unrealistic. Perhaps this ranking is an artificial device that serves to fit organisms into an evolutionary order.
We can't know what is truly simple or truly complex. We'd like to think that our scientific knowledge is quite advanced. But only a fraction of any organism's complexity is really understood. Appearances do not tell us what a trait is for. We can only guess at whether or not a given trait provides greater adaptation. There is no measurement for determining degrees of complexity.
The construction of a single cell is a good example. Its complexity, efficiency, miniaturization, and automation are beyond anything that scientists are capable of designing. Consider the flagellum, a hair-like structure of certain bacteria. The flagellum turns by means of a rotary motor system that is more high-tech than anything man has been able to produce. An electric motor causes a series of wheels to rotate on an axle, which puts torque (turning force) on the flagellum and causes it to move, spinning on a friction-free bearing surface at more than 18,000 RPMs (revolutions per minute). The electrical current is produced by the cell membrane and controls the speed of the spin.
Now consider that the bacteria itself is microscopic and that this spinning apparatus is only a few billionths of an inch in diameter. This is the most primitive life form we know. According to the theory of evolution, the rotary motor of the flagellum is the product of time and chance. No intelligence went into planning this system.
Man cannot yet produce a comparable motor. But if you looked at a motor that man has produced, how would you assume it originated? Would you assume that the pieces somehow had formed all by themselves, and had somehow assembled themselves, and had somehow ended up as this finely tuned motor?
Another engineering marvel is nature's solar energy conversion plant--the chloroplast. Only recently has mankind been able to convert the sun's energy into usable power. Solar energy doesn’t automatically meet our needs. It is useless without some sort of system to collect, organize and distribute it.
Ever since the first green plant lifted its leafy face toward the sun, the chloroplast has been efficiently converting sunlight into sugar to feed the plant's cells. This process is called photosynthesis. If the first green plant needed the chloroplast to survive, how did it evolve? What came before? Where is the evidence of a step-by-step development of this obviously complex process?
Was the hydraulic pressure system invented by man? No--it too can be found in nature. It provides the means of transportation for the lowly starfish, another "primitive" organism. Its water-vascular system and its tube feet operate by taking in outside water, then forcing it into the tube feet by means of muscular contractions, which extend the feet. This system operated in the earliest known fossils. Where are the many intermediate forms leading up to this complicated hydraulic system? There are none.
If Darwin had known how complex life was at the cellular level, would he have been so sure that it all happened by chance?
If evolution did take place, there must be some natural mechanism that is capable of bringing about change. Remember that evolution must have happened by natural processes that are operating today. To explain it any other way would imply that miraculous, one-of-a-kind events took place, or that supernatural forces were at work. These kinds of events do not fit into the definition of evolution.
What natural process has been discovered to be the cause of evolution? Natural selection is a tautology. Mutations are mathematically incapable of bringing about evolution. Unable to produce new genes, they only change or delete existing ones.
It is difficult to understand how evolution could have happened by slow gradual processes, one mutation at a time. It is just as difficult to understand how it could have happened fast, by many related mutations taking place at once. Random change is unable to improve a man-made computer program, much less a living cell or a complete organism. Random change is unable to bring about new information. Even billions of years are too short for the impossible to have occurred.
We have seen that microevolution does occur--changes on a small scale. However, it has not yet been demonstrated that many small changes will eventually add up to big changes. Darwin's Origin of Species contains only examples of microevolution. The conclusion that macroevolution could happen in the same way results from a misuse of extrapolation. Biology books are full of examples of microevolution, but do not have even one example of macroevolution. Instead, they often contain outdated, unscientific arguments for evolution such as homology, embryology, and vestigial organs.
There is no solid evidence that one kind of organism can change into another. Artificial breeding has proved that there are limits to how much change an organism is capable of.
Molecular biology has further weakened the case for evolution, in spite of many claims to the contrary. Studies at the chemical level show no relationship between the various kinds of creatures and no evidence of descent from a common ancestor. What the microscope does show is an amazing degree of complexity at all levels of life.
In Darwin's day, the lack of complete knowledge was a plus for evolution. Scientists could confidently assert that the missing information would be found eventually. Just the opposite has happened. The growing pile of data continues to cast doubt on the theory, rather than fill in the gaps and remove the question marks.
Has the science of biology provided a realistic mechanism to explain the evolution of life? If evolution did take place, it must have been by some process that has not yet been discovered.
Copyright 2003 Jan Young
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