In this blog post, we will look at how altruistic behavior has survived through evolution, focusing on the group selection hypothesis.
How did giraffes, which used to have short necks, develop long necks? Why are moths, which used to be mainly white, now mostly black? Why are modern pests not easily killed by pesticides? The answer is closely related to Charles Darwin’s theory of natural selection. Natural selection is a phenomenon in which only individuals with characteristics suitable for survival in a given environment survive and pass on their genes to their offspring.
According to Darwin’s theory, species change in accordance with their environment as individuals that are suited to survival are selected. In the case of giraffes, individuals with long necks can eat leaves from tall trees, giving them an advantage in their environment, and as a result, more individuals with long necks have survived. This is a representative example of natural selection, clearly showing how nature selects and changes species.
However, according to natural selection, when selfish individuals compete with altruistic individuals, the selfish individuals will remain and the altruistic individuals will be eliminated and disappear. How did the altruistic individuals survive? There are various hypotheses regarding this issue, which could be considered a major flaw in the theory of evolution, but I will explain one of them to support the theory of evolution.
Group selection is a concept similar to natural selection, but it applies to different subjects. While natural selection, as explained above, focuses mainly on “individual selection” that acts on individuals, such as a single giraffe or a single moth, “group selection” assumes that “natural selection” acts on groups rather than individuals. Therefore, when group selection acts, groups with many individuals possessing characteristics and traits best suited to a given environment are more likely to survive, while groups that are not are more likely to be eliminated by natural selection. For example, in primitive times, groups of people with genes for large bodies would have had an advantage over groups of people with genes for small bodies in an environment where strength was important for hunting and gathering, and as a result, they would have survived for a long time. Of course, in this case, there is no significant difference between individual selection and group selection. This is because both individual selection and group selection favor genes for large bodies.
The difference between individual selection and group selection arises when there are altruistic groups and selfish groups. What happens when group selection occurs between altruistic groups and selfish groups? Since ancient times, altruistic people have been much more helpful to society as a whole than selfish people. This is because altruistic people consider the interests of the group as a whole rather than their own interests, while selfish people prioritize their own interests above all else. For example, when war breaks out, altruistic people will fight much more bravely and actively than selfish people for the victory of the group, so if other conditions are similar, a group composed of altruistic people is much more likely to win the war than a group that is not. In this way, at the group level, we can see that groups with more altruistic people than selfish people are much stronger in a given environment or society. Therefore, groups with a high proportion of selfish individuals are eliminated through group selection, and groups with a high proportion of altruistic individuals survive, allowing altruistic individuals to continue to exist. If individual selection occurred, selfish individuals would survive and altruistic individuals would be eliminated, but when group selection occurs, the opposite situation occurs.
The principle of group selection is also at work in various ways in modern society. For example, organizations that value teamwork and cooperation within the company are bound to achieve higher performance than those that do not. This shows that altruistic behavior is an important factor contributing to the success of a group. In addition, societies that help the socially vulnerable and promote the welfare of the community are more stable and sustainable than those that do not. These phenomena prove that group selection is not just a theoretical concept but can also be applied in reality.
As such, is based on “group selection,” which is natural selection targeting groups. Through group selection, only groups with many altruistic individuals, who are advantageous for survival at the group level, could survive, and altruistic individuals, who are at a disadvantage in individual selection, could survive. However, there are two flaws in . First, group selection occurs at a slower rate than individual selection. Even in groups with many altruistic individuals, individual selection occurs at a faster rate than group selection, so altruistic individuals will disappear before group selection can occur due to selfish individuals. Furthermore, the root cause of group selection is the difference in characteristics between selfish and altruistic groups. However, in the process of group selection, groups disappear and differences between groups diminish, making group selection more difficult. In order to solve these problems, it seems that research on “institutions” unique to humans will become even more urgent in the future.
In particular, in human society, institutions such as laws, morals, and culture play an important role in regulating individual behavior and promoting the interests of the group. Such institutional mechanisms can accelerate group selection by suppressing selfish behavior and encouraging altruistic behavior. For example, environmental laws that protect public goods promote altruistic behavior, and social welfare systems increase the stability of the group as a whole by protecting the weak within the community. These institutions provide a foundation for the principle of group selection to function effectively in reality.
In conclusion, explains an important mechanism that allowed altruistic behavior to survive and thrive during the evolutionary process. Although there are theoretical limitations, institutional research and application to complement these limitations are essential for the development of our society in a better direction. It is important to understand that altruistic behavior is not a simple sacrifice but a strategic choice for the prosperity of the group, and through this understanding, we will be able to create a more cooperative and sustainable society.
