What are the different theories and controversies in evolutionary theory and what can we learn from them?

Explores the different theories and controversies in evolutionary theory, giving my opinion and emphasizing the importance of scientific debate. The theory of evolution is explored from a scientific point of view, without any conflict with religion.

 

Evolution is a theory that most people living in the modern world have come across at least once. Although it has been over 150 years since its publication, there are still many controversies, both big and small. On the one hand, there is the conflict between those who believe in creationism, mainly religious people, and those who support evolution, mainly in the scientific community, and on the other hand, there is the conflict between different theories within evolutionary theory. However, the conflict between creationism and evolution is a big conflict because it is a conflict between science and religion, which is not logical in the first place, but I don’t think it is meaningful to compare the two, so in this article, I will look at the various theories of evolution from a scientific point of view and share my opinion.
What is the orthodoxy of evolutionary theory? To find out, I’m going to focus on some of the current controversies in evolutionary theory. In this article, I’ll discuss the timing of evolutionary theory, the units of evolution, opinions on the role of genes, views on adaptation, and the relationship between evolution and progress.
We usually know the theory of evolution as the survival of individuals that are better adapted to the environment through natural selection and the accumulation of inherited traits, but there is a lot to think about when we look deeper. First, let’s talk about the timing of evolution. There are two main theories of evolutionary time: interrupted equilibrium and gradualism. The interrupted equilibrium theory states that the evolution of biological species occurs in a short period of time with rapid differentiation. In species above a certain size, even if a mutation occurs, the mutation does not have a large effect due to gene flow between groups and it is difficult to differentiate, but if a small group is isolated, the effect of gene flow is weakened and species differentiation by mutation occurs. Gradualism, on the other hand, is the theory that speciation occurs gradually rather than abruptly, as in intermittent equilibrium. In other words, speciation is always happening, whether slowly or quickly. Here’s an analogy In the process of returning to Israel, the Israelis traveled a distance of about 320 kilometers over 40 years. The interrupted equilibrium theory would say that the Israelis stayed settled for most of the 40 years and then at some point moved 320 kilometers quickly, while the gradualist theory would say that they moved in small increments over the 40 years and arrived in Israel. It’s important to note that the gradualist doesn’t say that they move in a steady state over the 40 years, but rather that they move forward in some direction over those years, so I’m inclined to side with the gradualist between these two theories. While the intermittent equilibrium theory argues for rapid divergence at certain times, the gradualist’s position is that these events are part of a long period of change. In other words, there will be periods of slow evolutionary change, and there will be periods of rapid divergence, closer to Gould’s intermittent equilibrium theory. But the important thing is that evolution is always happening, regardless of the time period. Whether it’s slow or fast, it’s moving forward. Therefore, I believe that gradualism, which can encompass other theories, is a theory that is closer to the truth.
Next, let’s talk about the units of evolution. Dawkins advocates genetic selection and Gould advocates multilevel selection. Conceptually, it might seem that multilevel selection is the superior theory to genetic selection because it sees genes, individuals, and species as all units of evolution. However, it’s not that simple. The question is at what level is natural selection really operating, since it is the phenotypes of genes that cause individuals and species to have certain traits (e.g., blue-eyed people have less pigment), so if individuals and species are the units of natural selection, this is no different than if they were selected at the level of genes. In his book The Selfish Gene, Dawkins said “Genes do not directly puppeteer themselves, but indirectly control the behavior of their own survival machinery, like the programmers of a computer. What genes can do is create the framework of the survival machine in advance. After that, the survival machinery is completely independent, and the genes are just passive in it.” In other words, even if the individuals programmed by the genes and the species of which they are a part are active and subject to natural selection, the cause can be attributed to the program of the genes. Therefore, I think the theory of gene selection is more convincing.
The next topic is the role of genes, which is arguably the most important in the discussion of evolutionary theory. Once this is clearly understood, questions about the timing of evolution before facts, questions about the units of evolution, and questions about the scope of adaptation (how much of it should be considered adaptation) will all be resolved. However, the exact role of genes is still highly debated, and many studies are still ongoing. That’s why there’s so much debate about how much influence genes have. Dawkins believes that genes strongly influence phenotypes and are the main players in evolution, whereas Gould believes that both genes and the environment (including not only the environment an individual experiences, but also the environment inside the cell) are important. The boundaries between these two theories are not always clear. There are studies that use twins to look at the effects of genetics and environment, but depending on the field, genetics and environment can be equally influential, or genetics can be dominant, or environment can be dominant. In other words, there is no absolute advantage. For example, in a study of twins on prosocial behavior, both genes and environment played a role, with genetic factors increasing from 32% to 61% with age, and the effect of shared environment decreasing from 47% to 3%. For this reason, I support Gould’s position because while Dawkins’ idea that genes are central may be important to the basic foundation of how organisms are made, the influence of the environment cannot be ignored in how organisms eventually live, grow, and survive.
Next, consider the debate about adaptation. Adaptation is a major driving force in evolution. Natural selection favors organisms that are better adapted to their environment. However, it’s hard to know how far this adaptation has gone. For example, consider the human ability to speak. Dawkins would argue that language is an adaptation of survival of the fittest, while Gould would argue that language is a byproduct of the enlargement of the human brain and its increased processing power. Of course, there are genes that affect language, so we can’t ignore the fact that language is an adaptation. Another example is rape, where adaptationists see it as an adaptive behavior for survival of males who fail to reproduce, while anti-adaptationists see it as a byproduct of selfish behavior. In fact, the existence of insects that are naturally equipped with organs for rape is used as evidence by the adaptationists. Conversely, the fact that rape also occurs in older women and children who are far from reproducing is evidence for the anti-adaptationist. The point is that much more research is needed to clarify the scope of adaptation. Only after a sufficient foundation has been laid will we have a clear answer to this question. So, for now, it’s best to focus on the research rather than slandering 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 word progress itself contains value judgments, it’s inevitable to consider values in the phenomenon of evolution. If we define progress as simply an increase in the diversity of organisms, then we can say that evolution is progress. However, it is questionable whether the existence of multicellular organisms, the so-called higher organisms, is progressive. As Gould explains with the example of the drunkard model, the current direction of evolution is toward complex multicellular organisms because there is a barrier of unicellular organisms, but whether this direction is progress is a different question. Therefore, I think we should be careful about making value judgments about progress in the phenomenon of evolution. While it’s good to think about and embrace the emergence of humanity through evolution as a positive thing, misusing it can have far-reaching consequences, just as early imperialists misused Darwin’s theory of evolution to think they were superior and their colonizers were inferior.
So far, I’ve talked about the evolutionary debate, focusing on the positions of Dawkins and Gould, two of Darwin’s descendants, and shared my thoughts on them. I’m sure many things will become clearer as more research is done, but the debate will continue. My hope is that these debates will have a positive competitive effect, helping to reduce errors in research and bring us closer to the truth. It is not helpful to have a debate that is as destructive as the one that the religious community has recently had with theistic evolution, which blindly denigrates the scientific community. If we are truly Darwin’s descendants, we should look at evolutionary theory with scientific arguments and explore it, and who knows, maybe one day we will be able to achieve the discovery of absolute truth that some scientists dream of.