Altruism is a behavior that is detrimental to the individual, but the theory of group selection explains that altruistic behavior is beneficial to the survival of the group. However, the evolution of altruism is still a matter of debate, as selfish individuals may be better off.

What is altruism?

Altruism is one of the most mysterious aspects of human nature, and defining and explaining it has long been a fascination of philosophers, psychologists, and biologists. Altruism can be simply defined as acting for the benefit of others at the expense of one’s own self-interest, or “doing something to benefit others at the expense of one’s own self. However, as we delve into its nature and origins, we realize that the definition is far from simple. In human society, altruism is sometimes seen as a moral and social norm, and many cultures hold it up as a virtue. But it’s still an interesting topic to explore whether altruism really comes from pure intentions, or whether it stems from a deeper instinct or survival strategy.
Let’s say you’re traveling down the road one day and happen to come across an alien in trouble and decide to help him out. The alien, now out of danger, thanks you and asks you something like this.
“Thank you so much, I admire your altruism, is your whole species like this, and if you don’t mind me asking, can you tell me what makes your species so selfless?”
If you were in this situation, how would you answer? You might say it’s because of the moral education you received as a child, or you might say it’s because of the compassion and sense of social responsibility that humans naturally feel. But how did altruism actually come about? Unfortunately, no one has a definitive answer to how altruism arose. Instead, scientists have proposed a number of theories, one of which is the “group selection theory.” Let’s take a look at what it is, how it explains the existence of altruism, and how well it works.

Why do selfish individuals have an advantage in survival?

Before we dive into the theory of group selection, let’s be clear about what altruism is. In sociobiology, altruistic behavior is defined as “behavior that is detrimental to the actor, but beneficial to society as a whole.” Initially, your helping the alien is an altruistic act because you sacrificed your time and energy to help the alien. Altruistic entities sacrifice themselves to benefit others, while selfish entities seek to minimize their own sacrifice. Therefore, when altruistic and selfish entities are together, the selfish entity’s strategy is much more successful because the altruistic entity will only lose and the selfish entity will only gain. Sooner or later, the altruistic individuals in the group will be culled out, and only the selfish individuals will survive through natural selection. This process of increasing the number of individuals with a trait when it is advantageous for them to survive is known as “individual selection”.

Are altruistic groups favored to survive?

Now let’s think about this from the perspective of a group rather than an individual. If we define altruistic behavior as we did earlier, it’s natural to speculate that societies with more altruistic people are more likely to be successful than societies with more selfish people. This is what scientists call the “group selection” hypothesis. The idea is that when you have a relatively altruistic group and a selfish group, the altruistic group will be naturally selected for because it has an advantage in survival, and the selfish group will be culled.
According to Professor Jung Kyu Choi, a world-renowned expert in behavioral economics, altruism is a competitive advantage for societies, as groups with more altruistic people were more likely to survive the frequent wars of the caveman era, were better nourished through cooperation in hunting and gathering, and were able to successfully defend themselves against numerous threats during the Ice Age. Even in modern societies, cooperation and altruism within groups are considered essential for social stability and prosperity, and are constantly reinforced through education and legal systems.
As we’ve seen, group selection and individual selection theories are in direct opposition to altruism: according to group selection, altruistic groups will survive, and according to individual selection, only selfish individuals will survive. But what about the real world we live in? As we know, altruistic behavior can still be found in many people. So is group selection right and individual selection wrong, or is group selection superior to individual selection?

Individual vs. collective selection

Let’s assume that both individual and group selection are valid rules. In this case, it is the speed of the process under either hypothesis that determines whether evolution is more altruistic or selfish. In order to evolve altruistically through collective selection, the process of collective selection must be faster than individual selection, but many scholars disagree. In most cases, the speed of individual selection overwhelms the speed of group selection. In addition, the genes of altruistic individuals who sacrifice themselves for others are less likely to be passed on to the next generation than those of selfish individuals. However, it’s still too early to give up on the theory of collective selection. This is because there are mechanisms in place in our society that increase the effectiveness of group selection, slow down the rate of individual selection, and consequently protect altruistic individuals. Unique to human societies, these mechanisms exist in the form of institutions.
It is commonly assumed that the speed of individual selection is proportional to the difference between the average payoffs of altruistic and selfish individuals. If there is no regulation in society, selfish individuals will always be able to take home more pay than altruistic individuals. What if we introduce institutions to force the difference in average pay to decrease? Consider the most rudimentary of institutions: food redistribution in hunter-gatherer societies. Common ownership and equal redistribution of food can significantly reduce the difference between the payoffs of altruistic individuals (those who forage for food) and selfish individuals (those who don’t forage for food). If the difference in payoffs between selfish and altruistic strategies is not large, there is less incentive to stick with the selfish strategy. In other words, individual choice is slowed down, and collective choice is empowered.
In addition to these institutions, there are many other social mechanisms in modern society. For example, social trust and reputation, or legal sanctions, are important factors that discourage individuals from acting selfishly and prioritize group interests. These mechanisms allow altruistic behavior to become more common, which in turn increases the likelihood that we will evolve into the cooperative and altruistic society that the theory of group selection emphasizes.

Is group selection the only answer?

Let’s go back to our first alien rescue situation. While there’s no perfect answer to how altruism arose, isn’t it fair to say that group selection works well enough to provide a plausible explanation for its existence? Unfortunately, it’s not quite that simple: group selection can’t explain all the altruistic behavior on Earth – altruism among different species, and the extreme altruism found in animals that don’t have sophisticated institutions like humans, needs to be explained by another theory.
There are also many scientists who doubt the very existence of group selection, arguing that the unit of evolution is the gene, not the group or individual. The altruistic acts performed by groups and individuals are just selfish acts of survival from the point of view of the genes. Since the publication of Richard Dawkins’ The Selfish Gene, a book that addresses this theory, the theory of group selection has been losing steam. However, the argument that group selection was more important than the genetic level for the evolution of social behaviors like altruism is also strong, and it seems like a debate that won’t end anytime soon.
In the end, the debate over the origins and role of altruism remains an important key to understanding our nature, and as long as it remains unresolved, the quest for human nature will continue.