Evolution is the theory that organisms change as they adapt to their environment, and there are ongoing debates about the timing and scale of evolution, the role of genes and the environment, and the relationship between evolution and progress. Whether it’s gradualism versus stochastic equilibrium, genetic selection versus multilevel selection, the limits of adaptation, or the value of evolution and progress, scientists have different perspectives on these issues, and they all try to get closer to the truth through research.
Evolution is a theory that most people in the modern world have heard of at least once. It’s been over 150 years since its publication, but there are still controversies, big and small. On a larger scale, there’s the conflict between religious people, especially those who support creationism, and the scientific community, especially those who support evolution, and on a smaller scale, there’s the conflict between different theories within evolution. However, the conflict between creationism and evolution is a conflict between different approaches to science and religion, so it is difficult to fully establish logically, and it is not meaningful to compare the two. Therefore, in this article, I will look at the various theories of evolution from a scientific point of view and give my opinion.
To explore what is orthodox in evolutionary theory, I will base my discussion on some of the main issues that are currently being debated in evolutionary theory. This article will focus on the timing of evolution, the units of evolution, the role of genes, views on adaptation, and the relationship between evolution and progress.
The theory of evolution is often understood as the survival of individuals that are better adapted to their environment by natural selection, and the inheritance of those traits. However, there is a lot more to think about when you dig deeper. First, let’s look at the timing of evolution. There are two main schools of thought on this topic: punctuated equilibrium theory and gradualism. The punctuated equilibrium theory explains that species evolve in short bursts of speciation. In species above a certain size, gene flow between populations is unlikely to produce significant changes, even when mutations occur, but when small populations are isolated, the effect of gene flow is reduced, allowing speciation to occur. Gradualism, on the other hand, views speciation as a continuous process, whether slow or fast, rather than a sudden divergence.
For example, imagine that the Israelis traveled a distance of about 320 kilometers over 40 years on their way back to Israel. Intermittent equilibrium theory would explain that the Israelis stayed settled most of the time and then at some point moved 320 kilometers quickly, whereas gradualism would say that they moved in a steady direction for 40 years and arrived in Israel in small steps. Note that in this analogy, the gradualist is not claiming that they traveled in a steady state for 40 years, but rather that they moved in a direction over those years, so I’m more sympathetic to the gradualist. This is because while intermittent equilibrium theory argues for sharp divergences at certain times, the gradualist position is that these can be interpreted as part of a long process of change. Evolution is a continuous process, whether it happens slowly or quickly, and I believe that gradualism, which can encompass other theories, is a more truthful explanation.
Next, let’s discuss the units of evolution. On this topic, Dawkins advocates genetic selection and Gould advocates multilevel selection. Multilevel selection may seem like a superior theory to genetic selection because it views genes, individuals, and species as all units of evolution, but it’s not a simple question. The question is at what level does natural selection operate, since the traits of individuals and species are ultimately attributable to the phenotypes of their genes, so even if individuals and species are the units of natural selection, they are no different from those selected at the gene level. In his book The Selfish Gene, Dawkins writes, “Genes control the behavior of the survival machine indirectly, like the programmers of a computer, without directly manipulating the puppets. What genes can do is design the survival machine in advance. After that, the survival machinery works independently, and the genes are passively present in it.” In other words, even if individuals and species are subject to natural selection, it can be seen as a result of the influence of genes. From this perspective, I find the theory of genetic selection more convincing.
The following is a discussion of the role of genes, which is a key topic in evolutionary theory. Once this is clarified, questions about the timing of evolution, the units of evolution, and the scope of adaptation (what counts as adaptation) will be resolved. However, the precise role of genes is still debated and actively researched. Dawkins believes that genes have a strong influence on phenotype and are the main players in evolution, while Gould argues that both the internal and external environment of an individual is important, not just genes. Twin studies continue to compare the effects of genetics and environment, but the proportions of genetics and environment vary depending on the topic, so it’s hard to say which has the absolute upper hand. For example, in a study of prosocial behavior, genetic factors increased with age from 32% to 61%, while the influence of shared environment decreased from 47% to 3%. Therefore, I am more inclined to agree with Gould’s position that while Dawkins’ gene-centric view may be significant for the basic traits of an organism, the influence of the environment cannot be ignored when it comes to growth and survival.
Next, let’s look at the debate over adaptation. One of the main driving forces of evolution is adaptation. This is because natural selection favors organisms that are better adapted to their environment. However, it’s not easy to figure out how far adaptation goes. Take the human ability to speak, for example. Dawkins believes that language arose as a survival and adaptation of language-speaking individuals, while Gould believes that language arose as a byproduct of the enlargement of the human brain and its increased processing power. Of course, there are genes that affect language, so it’s possible that language could be a product of adaptation. Another example is rape, which is viewed by adaptationists as an adaptive behavior for survival of males who fail to reproduce, and by anti-adaptationists as a byproduct of simply selfish behavior. In fact, the existence of a species of insect called a dipteran with a rape organ is evidence for the adaptationists, while the fact that rape also occurs in women and children at ages far removed from reproduction is evidence for the anti-adaptationists. Further research is needed to clarify the debate on the scope of adaptation, and only after a sufficient foundation has been laid will there be a clear answer, so for now, it is better to gradually clarify the issue through research rather than slander each other.
Finally, I’d like to conclude by talking about evolution and progress. The relationship between evolution and progress depends on how we define ‘progress’. Since the term progress itself contains a value judgment, it is inevitable that we assign a value to the phenomenon of evolution. If we define progress as an increase in biodiversity, then evolution can be seen as progress. However, it is questionable whether higher organisms, such as multicellular organisms, are progressive. As Gould explains in his “drunkard’s model,” the barrier of unicellular organisms means that the current direction of evolution is toward complex multicellular organisms, not necessarily progress in and of itself. I think we need to be careful about making value judgments about the phenomenon of evolution as progress. While it’s good to embrace evolution as a positive thing, the wrong value judgment can have devastating consequences, just as early imperialists misused Darwin’s theory of evolution to claim superiority.
In this article, I have discussed the controversy of evolutionary theory, focusing on the views of Dawkins and Gould, two of Darwin’s descendants, and presented my own thoughts. As research continues, many things will be clarified and clarified, and the debate will continue. My hope is that these debates will have a positive competitive effect, reducing errors in research and bringing us closer to the truth. The current debate, in which the religious community comes out with theistic evolution and criticizes the scientific community, is not conducive to progress. If we are true descendants of Darwin, we should explore the theory of evolution through scientific arguments. Maybe, just maybe, humanity will one day discover the absolute truth that some scientists dream of.