Richard Lenski is an evolutionary biologist who has studied the bacterium E. coli for more than 65,000 generations since 1988, equivalent to 2 million years for humans. During this time, numerous changes have occurred in the bacteria, demonstrating microevolution. Michael Behe has analyzed Lenski’s results in more detail and presents them in his book “Darwin Devolves” from 2019. He writes: “Detailed, purely evolutionary studies have only begun to be conducted in the last twenty years. Now, thanks to the fantastic work of many biologists, made possible by unparalleled advances in laboratory techniques, we are in a much stronger position to judge Darwin’s theories based on good experiments, not just preconceived postulates. New studies clearly show that there are strict limits to what random mechanisms can lead to in terms of fundamental biological changes – even though they clearly show that Darwinian processes can drive small-scale adaptation.”
Behe discusses three factors that limit what evolution can achieve: Irreducible complexity, which we discussed earlier, is an important factor, but evolution’s two main mechanisms – random mutations and natural selection – both limit what evolution can accomplish in the long run. Evolution thus becomes self-limiting. Lenski’s experiment showed that mutations increased the growth rate of the bacteria. As more mutations occurred, this rate increased further. The end result was that the growth rate became approximately double the original rate. However, all mutations that had this effect destroyed other genes in the bacteria. The increased growth rate thus came at a price.
When examining 30 selected genes over a longer period, it was found that 15 genes were eliminated from the DNA, so the proteins these genes coded for were no longer present. The remaining 15 genes were all damaged, so the proteins were degraded. We can distinguish between three types of mutations: useful, constructive, and destructive. Destructive mutations were the most frequent in Lenski’s experiment. Some of these mutations can still be described as useful since they increased the bacteria’s growth rate, but they always led to the loss of other functions. When a constructive mutation occasionally occurs, many destructive mutations have happened first. For example, the bacteria’s ability to repair DNA damage may have been lost. In Lenski’s experiment, almost all useful mutations either damaged or destroyed genes that were present in the original bacteria. Behe claims that this is the norm and has presented a rule stating that evolution always leads to the loss of genes. There are many more opportunities for an organism to gain an advantage by breaking something down than by building something new. In this E. coli experiment, nothing new was formed, no new proteins or machines.
The task of natural selection is to preserve what works and remove what is damaged and has reduced function.
All mutations that provide a short-term advantage or gain will eventually be harmful because some of the host’s DNA is broken down. The vast majority of mutations that are advantageous for adaptation will damage an organism’s genetic information – either by degrading or directly destroying functional elements. This means that Darwinian evolution essentially occurs by damaging or losing genes. Occasionally, this leads to a short-term gain. In the long run, this makes evolution self-limiting. There is a limit to what evolution can lead to.
Mutations can sometimes be beneficial for organisms in some way. Some mutations can, for example, be beneficial for bacteria since they develop resistance to certain antibiotics. Such mutations give the bacteria an advantage (but not for the patient, as the disease may become harder to cure). In humans, there is a mutation that allows one to eat a lot of sugar without developing diabetes. However, this mutation also leads to the loss of a protein. Genetic studies have also been conducted on various dog breeds, and it is found that breeding leads to the loss of genes in DNA.
We have previously discussed the biological classification system. Professor Behe specifies: “Darwinian processes can explain changes at the species and genus level of biological classification, but not changes at the family level or higher.” This means that evolution cannot explain macroevolution. Evolution can therefore only lead to relatively small changes. If we think of an amount of 100,000 USD, such changes would be limited to the level of cents.
This has led Michael Behe to conclude: Evolution lives off its genetic inheritance. It thus appears that life starts with complete DNA, which over time loses parts of its information due to mutations. This is the exact opposite of what evolutionary theory claims. It explains why mutations lead to a long list of diseases in humans. It is not evolution that occurs over time, but rather the opposite, which we can call devolution.
Lenski’s experiment is the most systematic evolutionary experiment conducted, and it shows no signs of macroevolution, the development of a new type of bacteria, as one might have hoped. E. coli remains E. coli. There are no laboratory experiments that have demonstrated macroevolution.
Evolutionary theory is based on similarities. When the same structure is found in two different species, it is concluded that they are evolutionarily related. Similarity is interpreted as common ancestry and evolutionary relationship. Humans resemble apes, and evolutionists believe we share common ancestors with chimpanzees. However, when studying the differences between apes and humans, the differences are so significant that it becomes problematic to claim this. Many coordinated mutations are required to explain such development, and the available time is not long enough to accumulate sufficient mutations. Evolutionists believe the first step in the process that led to humans from apes occurred about 7 million years ago. It would take 84–100 million years to achieve two coordinated mutations in humans. The development of humans would require hundreds, possibly thousands, of mutations within 7 million years, which is understood to be impossible.
This article is from the book of prof emeritus Kjell J. Tveter “So much to wonder about”
