| Feature Article - February 2004 |
| by Do-While Jones |
What can we say? It is Valentine’s Day, and we have to think about things like that.
Bacteria seem to be the modern poster children for evolutionists. Evolutionists love to talk about bacterial resistance as evidence of evolution. This paragraph from an unidentified evolutionist is typical:
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For example, experiments with bacteria have confirmed that beneficial mutations occur. The entire DNA sequence of a bacterium can be mapped. A single bacterium can be cultured to form a colony. This colony can be subjected to antibiotics, and over time, a new colony of resistant bacteria may form. This experiment has been done, and knowing the exact DNA sequence of the original strain, we know that the new resistant strain formed resistance from a mutation. Therefore, the new mutation conferred an advantage to its bearer--in this case, resistance to antibiotics. 1 |
Before we deal with the specific issues raised here, let’s establish some background.
First, we need to establish what kind of evolution we are talking about. One definition of “evolution” is “change.” We all agree that people change as they grow older, but that isn’t the kind of evolution we are concerned with. The kind of evolution at issue has to do with the origin of the various kinds of life on Earth today, as is generally taught in American public schools. When deciding whether or not “evolution” should be taught in schools, the court defined “evolution” this way:
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So, we want to examine the undisputed change in a colony of bacteria in relation to its application to points 1 and 2 above.
Bacteria don’t reproduce like many larger life forms do. People, dogs, horses, corn, and pigeons all reproduce sexually. Their offspring inherit a mixture of characteristics from two parents. Many characteristics (size, shape, color, texture, speed, strength, etc.) are the result of genes inherited from parents. Natural selection (or artificial selection) determines which individuals mate, thereby establishing the characteristics of succeeding generations.
The shuffling of genes that results from sexual reproduction explains variation in species. Variation in species is different from the kind of evolution that is the subject of debate. One can breed dogs to be big or little, ferocious or gentle, but in the end they are all still dogs with different combinations of characteristics that have historically existed in dogs.
Variation in a species is like rearranging tiles in a ScrabbleTM game to form different words. The more letter tiles you have, the more different kinds of words you can make. But no matter how many different words you can make, it doesn’t explain where the tiles came from in the first place.
Shuffling existing genes can cause all sorts of variation, but it doesn’t explain where the genes came from in the first place. Evolutionists need some explanation for the origin of genes. Sexual reproduction doesn’t provide that explanation. Therefore, they turn to asexual reproduction, which is where bacteria come in.
The over-simplified (but incorrect) explanation of asexual reproduction believed by many people is that bacteria are single-celled creatures that reproduce by growing so big that they divide in half, resulting in two creatures with identical DNA. But, every once in a while, a mutation happens, causing a random change in the DNA, resulting in a slightly different species. These random changes result in new kinds of genes, which eventually accumulate, creating new kinds of creatures. This misunderstanding leads to comments like the quote at the beginning of this essay.
If you read a modern college biology textbook, you will find that it doesn’t really work that way.
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Transformation May Combine DNA from Different Bacterial Species Bacteria employ several methods of recombination that allow gene transfer between unrelated species. A process called transformation allows bacteria to pick up free DNA from the environment. The free DNA may be part of the chromosome of another bacterium, including DNA from a bacterium of another species. Transformation may also occur when bacteria pick up tiny circular DNA molecules called plasmids (Fig. 13-1). Plasmids, which range in size from about 1000 to 100,000 nucleotides, are self-replicating lengths of DNA normally found in the cytoplasm of many types of bacteria and some yeasts. A single bacterium--a host cell--may contain dozens or even hundreds of copies of a plasmid. Although the bacterium’s “own” chromosome contains all the genes the cell normally needs for survival, the genes carried by the plasmid may also be useful. For example, some plasmids contain genes that code for enzymes that digest certain antibodies, such as penicillin. In environments where exposure to antibiotics is high, such as hospitals, these plasmids spread quickly, conferring a major advantage to their bacterial hosts and making antibiotic-resistant infections a serious problem (see Chapter 19). A bacterium may acquire plasmids from its own strain or from other types of bacteria. These plasmids are either liberated into the environment when a bacterium dies or are exchanged between living bacteria. Viruses May Transfer DNA between Bacteria and between Eukaryotic Species Viruses, which are little more than genetic material encased in a protein coat, transfer their genetic material to cells. There viral genes replicate and direct the synthesis of viral proteins. New virus particles are assembled inside the cell, then released to repeat the cycle (Fig 13-2). Viruses may transfer genes among bacteria and among eukaryotic organisms, such as plants, as well. Bacteriophages, specialized viruses that infect bacteria, occasionally acquire pieces of bacterial DNA. The bacteriophages, or phages, then release this DNA into other bacteria that they infect. In some cases, the transferred bacterial DNA becomes incorporated into the host bacterial chromosome, adding new genetic material. 3 [bold and italics in original] |
So, there is gene transfer between bacteria of the same species, and between bacteria of different species, and between bacteria and non-bacteria.
Knowing this, let’s look at the evolutionist’s argument at the beginning of this essay.
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The entire DNA sequence of a bacterium can be mapped. A single bacterium can be cultured to form a colony. |
Actually, scientists need more than a single DNA molecule to create a DNA sequence. DNA is generally “amplified” using a technique called Polymerase Chain Reaction (PCR), which is a kind of artificial reproduction where the DNA molecules are split lengthwise and the two halves are used as templates to create two more identical DNA molecules. The process is repeated until there is enough DNA to analyze. Just like natural reproduction, there is a possibility that copying errors may occur, so the map may not be entirely correct. But, the number of errors is so small that the map is good enough.
Of course, extracting the DNA from a bacterium kills it. So the single bacterium used to culture an entire colony can’t be the same one that is mapped. Dead bacteria don’t reproduce. We could nit-pick the premise of the evolutionist’s argument, but we won’t because the premise is generally true. One can culture a reasonably homogeneous colony of bacteria, of which one can obtain a DNA map, even if it can’t be done exactly as stated by the evolutionist.
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This colony can be subjected to antibiotics, and over time, a new colony of resistant bacteria may form. |
This statement is true, and the section of the biology textbook already quoted told us how this may happen. Some of the bacteria in the original colony may have had plasmids that protect against the antibiotic. Or, perhaps, some other bacteria with the resistance contaminated the colony at some point during the experiment, and some members of the original population acquired the plasmid from the contaminating bacteria. (This would be more likely in a hospital than in a carefully controlled experiment.) In the real world, where the bacteria aren’t part of a carefully cultured colony, the bacteria could acquire the plasmids from just about anything.
Furthermore, it is true that populations evolve, even if individuals don’t. Therefore, if 1% of a colony of bacteria happens to be resistant to a particular antibiotic, and if that antibiotic is applied to the colony for several generations, eventually 100% of the colony will be resistant. This is simply because the 99% were killed, and the 1% reproduced. The relative numbers of variations in the population changed (evolved), but nothing new was created.
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This experiment has been done, and knowing the exact DNA sequence of the original strain, we know that the new resistant strain formed resistance from a mutation. |
Here is the major flaw in the reasoning. The new strain didn’t necessarily come from a mutation. In fact, it probably didn’t. The resistant colony was either the result of eliminating all the bacteria that didn’t already have the resistance to begin with, or the result of the bacteria acquiring some existing genetic material from another source. There is no reason to believe that applying the antibiotic caused a mutation that created a new kind of bacteria, or that a mutation that just happened to give resistance occurred coincidentally with the application of the antibiotic.
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Therefore, the new mutation conferred an advantage to its bearer--in this case, resistance to antibiotics. |
There are two errors in this statement. The first error has to do with the “mutation”, and the second error has to do with “advantage.”
There probably wasn’t a random mutation. It is most likely that the application of the antibiotic simply destroyed all the bacteria that didn’t already have the resistance, allowing those with the resistance to flourish. No bacteria actually changed--only the relative number of different variations of one bacterial species that was present to begin with changed.
The other possibility is that bacteria did “mutate” by acquiring existing plasmids from some other living source. But, they had many more opportunities to acquire the plasmid before the antibiotic was administered than they had after it was administered. So, it is really just a matter of timing.
In either case, the “mutation” was not the result of entirely new DNA being created from scratch by a mutation. The DNA already existed (inside or outside the bacteria) before the experiment began. No new genes were created.
Furthermore, evolution of new kinds of life does not depend upon “advantageous mutations.” It depends upon “creative mutations.” An existing characteristic might be advantageous in one situation, but disadvantageous in another. As such, natural selection will cause existing characteristics to become more or less prominent in a population. But what evolution requires is for new things to arise by mutation. Every kind of cell in your body (skin cells, nerve cells, muscle cells, blood cells, etc.) would have to be the result of a creative mutation. The origin of a new kind of cell isn’t the same as the function of an existing cell being more or less efficient in a particular situation.
So, the claim that “experiments with bacteria have confirmed that beneficial mutations occur” is not valid. Experiments with bacteria have simply shown that when genetic material is shuffled, it causes variety. Furthermore, natural or artificial selection (that is, environmental pressure) can cause some varieties to proliferate more than others.
It doesn’t matter if the existing genetic material is shuffled by sexual reproduction or viral invasion. It is still just shuffling existing genetic material. Variation in bacteria is more convincing evidence of evolution than variation in sexual creatures simply because most people don’t know as much about asexual reproduction as they do about sexual reproduction.
The more you learn about asexual reproduction, the more you realize why the evolutionary argument is wrong. This is why the chief weapon in the evolutionists’ arsenal is censorship. They dare not let young children learn that bacteria exchange genes just as much as sexually reproducing things do. If so, they would recognize that variation from normal asexual reproduction cannot result in the origin of novel DNA, which would result in new kinds of living things.
Furthermore, the more you learn about all the complicated steps in cellular reproduction4 and patterns of inheritance5, it becomes obvious that it could not happen by chance. Science is against evolution.
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Footnotes:
1
We received this second-hand via email. We don’t know the source.
2
McLean v. Arkansas Board of Education, January 5, 1982.
3
Audesirk & Audesirk, Biology, 5th edition, 1999, pages 230 - 231
(Ev)
4
ibid. Chapter 11
5
ibid Chapter 12