In this blog post, we will examine the evolutionary significance of altruistic behavior through the “costly signaling hypothesis.”
A long time ago, in Seogyo-dong, Seoul, South Korea, a tragic incident occurred in which the late An Chi-beom saved the lives of all his neighbors from a fire but lost his own life. He was trying to escape the fire but was worried about his neighbors who were still asleep, so he woke them up and ended up inhaling too much smoke. As we can see from this tragic incident, Mr. An Chi-beom could have easily escaped the fire, but he chose to save his neighbors instead. It is truly unfortunate that someone with such a selfless heart has passed away.
There are many examples of selfless people like this, such as firefighters who died while putting out fires, brave citizens who jumped into subway trains to save people who had fallen, and, from a slightly different perspective, brave soldiers who fought for their country in war. However, these selfless people are less evolutionarily stable than those who are not. In the examples above, they risk their lives and even sacrifice themselves to perform altruistic acts. Ultimately, altruistic people have a lower survival rate than those who are not, meaning that they are not evolutionarily stable. But how can altruistic humans, who are not evolutionarily stable, continue to exist?
There is an interesting hypothesis that can answer this question. It is called the “costly signaling hypothesis.” Costly signaling refers to the act of demonstrating one’s abilities to others by performing difficult tasks that others cannot easily do due to their lack of ability, thereby signaling to others that one is superior. One example is the lifestyle of the Ache tribe in Paraguay, which mainly consists of gathering and hunting.
This tribe has a unique culture in which the spoils of the hunt are divided equally among all members, regardless of whether they participated in the hunt or not (hunting is mainly done by men). Due to differences in ability among the members, there are always certain individuals who are successful hunters, while others only receive meat.
However, no one criticizes those who only receive meat. On the contrary, those who hunt a lot boast about their skills, and trying to monopolize the hunt is considered a serious offense. This is very different from our daily lives. In a society where give and take is taken for granted, when someone receives help from another person, it is natural for the recipient to want to repay the favor in the future.
The unique behavior of the Acehnese is difficult to explain by conventional rational thinking. Rational thinking means that when faced with two choices, one of which is beneficial and the other detrimental, one naturally chooses the one that is beneficial. In the case of the Acehnese, those who only take advantage of others are rationally pursuing their own interests. However, the skilled hunters of the Acehnese tribe are not acting rationally at all. Rather, they have continued to engage in altruistic behavior that is detrimental to themselves but beneficial to others, at the expense of their own energy and time. The number of men in the Ace tribe who are tired of supporting the freeloaders and are giving up hunting is increasing, so it seems that this tradition should not be maintained, but the tradition of the Ace tribe continues.
How this tradition continues can be explained by the fact that expensive signaling helps to resolve the information imbalance between individuals. To explain, among the men of the Ace tribe (those who send signals), men who are successful hunters (those with ability) can show their ability to others by sharing the meat they have hunted with those who are unaware of their ability (those who receive signals). Conversely, those who are unsuccessful at hunting and only eat what others provide (those without ability) will have no opportunity to appeal to others. Ultimately, this information becomes an important factor in choosing a mate, which motivates the men of the Acehnese tribe to devote themselves to hunting.
We can find examples of expensive signaling close to home, a typical example being corporate social responsibility. What is a corporation? Looking up the meaning of “corporation” in a dictionary, we find the following definition: An organization that produces and sells goods or services for profit. In short, a corporation is basically an organization that pursues profit. However, companies sometimes engage in volunteer activities at welfare centers and orphanages where people in need gather, or deliver daily necessities free of charge for their welfare. Such actions are not in line with the basic operating principle of a company, which is to pursue profit. Even socially renowned and successful companies, which are clearly successful because they are committed to profit, sometimes contribute more to society than smaller companies.
Such non-economic behavior by companies can be interpreted as sending expensive signals. Companies are making efforts to resolve information imbalances among consumers, and although this may seem like a loss for the company in the short term, it ultimately demonstrates the company’s ability and character to donate large sums of money to society. In other words, by doing so, the company can gain the trust of consumers and improve its corporate image.
So far, we have looked at examples of costly signaling through the social contributions of the Ache tribe and companies. In conclusion, altruistic acts explained by expensive signaling occur because there are factors that benefit the individual. Therefore, it is difficult to explain the actions of people who perform purely altruistic acts without expecting anything in return, such as jumping onto railroad tracks to save someone who has fallen or a grandmother who makes a large donation despite earning a meager living by collecting scrap paper.
As such, there is a limitation to the costly signaling hypothesis in explaining all altruistic behavior. However, let us recall Aristotle’s saying that “man is a social animal.” Humans cannot help but live in society and are constantly influenced by others.
In these relationships, individuals strive to be recognized by others, and logically, they know that such behavior will ultimately benefit them. Therefore, they will naturally continue to engage in altruistic behavior through costly signaling. Although the costly signaling hypothesis has some limitations in its application, it can be said to be an effective hypothesis for explaining the existence of altruistic humans in general.
