Biological evolution is a fact, however ardent its deniers may be. The supporting scientific evidence is overwhelming. Evolutionary apologists have had to make changes to their discourse, adapting it to the extent that their arguments have become quite ridiculous. For a time, some assumed that the biblical story of creation was literal. Based on the biblical account, Archbishop James Usher calculated that creation took place on October 22, 4004 BC. This contradicts the geological evidence that shows the age of the Earth to be about 4.5 billion years old and does not explain the existence of fossils of long-extinct animals estimated to be millions of years old.
No holy text mentions them. Specific explanations have been proposed to address these issues, such as God created fossils to prove our belief that dinosaurs went extinct because they didn’t get on Noah’s ark – but that they lived alongside humans before the flood. Of course, human and dinosaur fossils have never been found in the same geological strata. But this has not disappointed the most disobedient to evolution. Pictures of primitive humans coexisting with dinosaurs are frequent in religious literature.
There is also a school of thought that goes beyond the more radical arguments of creationists, but says that it is impossible to explain evolution without the existence of a previously established plan, or as they prefer to call it, intelligent design. This is an attempt to place the idea of God within the evidence of biological evolution, trying to camouflage any religious background to give it a patina of scientific thought. Supporters of intelligent design accept that living things evolve, but they think that this evolution requires a director, that it cannot happen by chance.
One of the most beautiful parts of the Darwin-Wallace theory of evolution is that it explains biological evolution in terms of changes that occur through chance and selection, driven by the circumstances of nature. This process does not require a higher being controlling the process or a map. The human species exists, but under other circumstances, it might not have existed. If things had been different throughout our planet’s history, its dominant species might now be fluorescent platypuses or technological ferns.
One of the arguments most often used by intelligent design proponents is that of insurmountable complexity. There are very complex biological structures, such as the human eye, which require the presence of many elements. According to the argument of the deniers of Darwinian evolution, these cannot have been formed by chance and the accumulation of small changes. But this is easy to refute. What happens in evolution is that some elements take on new functions. When it comes to proteins, it is common for many to have multiple and unrelated functions. Going back to our ocular example, there are animals today that still have eye structures that are more similar to those of our ancestors.
The best argument against intelligent design is all the evidence that, if there is a great designer, they are not all that intelligent. Closer biological study makes it clear that either it all happens by chance or that the person administering all this is a dolt. Biological evolution is like trying to renovate an already built house. You can’t tear it down and start over, but you can knock down a partition, expand a gate, or add another story. The different rounds of work will eventually overlap, as in cathedrals built over several centuries, in which different architectural styles coexist.
There are some structures that are useful at one point, but must adapt to a new era and adjust or can become a burden, in some cases, bring about the extinction of a species. An example of such a mid-course interruption solution would be the vas deferens that connects the testicle to the urethra, which now surrounds the urethra due to the fact that our ancestors’ testicles were higher. We could go on. Backaches, herniated discs and hemorrhoids are due to the fact that, for millions of years, we were quadrupedal and still not as efficient when it comes to walking on two legs.
We can mention the children who choke to death because their alimentary canal shares space with their respiratory tract, no matter how easy it would be to separate the two, severe infections cause by placing the main outlet of solid waste from the body near the genitals. And it’s not just in anatomy that design flaws can be seen. There are many biochemical pathways where the inhibition effect is observed, in which, thanks to genetic engineering, we can now improve. If we’re going to believe in a supreme creator, at least let them be competent.
The genetic code
The best evidence for evolution is found in our DNA. All living things share the same genetic code and this allows genetic engineering to exist. The gene of one organism can work in another, and thanks to this fact, we can produce human insulin in bacteria. If a supreme being created living organisms out of nothing, wouldn’t it be more logical to give each one a different genetic code? This would have prevented the transfer of genes between species and would suggest that all beings were created independently, as the Bible says.
JM Mulet is a professor of biotechnology.
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