In this blog post, we will examine how the tit-for-tat strategy can explain altruistic behavior in humans from an evolutionary perspective, focusing on the repetition-reciprocity hypothesis.
If you look around you, you will see people who engage in altruistic behaviors that benefit others at their own expense, such as donating blood, volunteering, or donating to charities. Such altruistic behaviors inspire many people and make society a warmer place. However, evolutionary theory explains that traits that are advantageous for human survival are more likely to survive, and altruistic behavior often does not help one’s own survival, so the two are contradictory. As a result, many scientists have proposed various hypotheses and experiments on how altruistic behavior emerged evolutionarily, one example being the kin selection hypothesis. This hypothesis explains altruistic behavior toward people who are related to oneself, but it cannot explain altruistic behavior toward people who are unrelated to oneself, such as blood donation. To supplement this, scholars have proposed the reciprocal altruism hypothesis. Let’s take a look at how the reciprocal altruism hypothesis overcomes the limitations of the kin selection hypothesis and resolves the contradictions between evolutionary theory and altruistic humans.
There are various hypotheses explaining the emergence of altruistic humans, such as kin selection, assortative mating, costly signaling, and communication. Among these, the reciprocal reciprocity hypothesis explains altruistic behavior through a tit-for-tat strategy. This strategy is based on the idea that if someone helps me, I will help them back, but if they do not help me, I will not help them either. According to the tit-for-tat hypothesis, assuming that interactions between people will continue, people engage in altruistic behavior because if they cooperate, the other party will also behave altruistically. In addition, if they do not behave altruistically, the other party will retaliate by not behaving altruistically toward them.
In other words, when people adopt a tit-for-tat strategy, they engage in altruistic behavior because it ultimately benefits them the most. An easy example of altruistic behavior through the repetition-reciprocity hypothesis is blood sharing among vampire bats.
As their name suggests, vampire bats feed on the blood of mammals, but they often fail to hunt successfully. When this happens, bats that have successfully hunted share the blood they have obtained with bats that have not. This is because when they fail to hunt, they will be able to obtain blood from the bats that helped them earlier, just as they did. Bats that do not share their blood cannot obtain blood when they fail to hunt and are naturally eliminated. The bats that performed the altruistic act of giving blood to others survived! The repetition-reciprocity hypothesis can be easily found in animal societies, not only in vampire bats, but also in the reconnaissance behavior of large spiny fish and the grooming of chimpanzees, and the same is true in human society.
As mentioned earlier, the kin selection hypothesis only explains altruistic behavior toward people who are related by blood. However, the repetition-reciprocity hypothesis can explain how altruistic behavior has evolved regardless of the target. However, the repetition-reciprocity hypothesis also has its limitations. The tit-for-tat hypothesis is based on the premise that actors repeat their actions, so acts such as willingly helping socially vulnerable people such as disabled people or elderly people whom one will never meet again, or leaving a tip at a restaurant in a foreign place, are altruistic but difficult to explain by the tit-for-tat hypothesis because they are one-time events. In this sense, the tit-for-tat hypothesis is like an archer without a bow. With the bow of repeated actions, the archer can shoot the arrow. In other words, when there is repetition of actions, the repetition-reciprocity hypothesis is a model that can explain altruistic behavior very well, but in the opposite case, it has clear limitations.
So far, we have looked at the repetition-reciprocity hypothesis regarding the emergence of altruistic humans. Altruistic behavior is difficult to explain from an evolutionary perspective, and scholars have proposed various hypotheses. Among them, the repetition-reciprocity hypothesis explains that people behave altruistically because if they do so, others will do the same for them. In other words, people adopt a tit-for-tat strategy. An example of altruistic behavior based on the tit-for-tat hypothesis is blood sharing among vampire bats. However, this hypothesis has limitations in that it only holds true when mutual behavior continues. Therefore, several theories have been proposed to compensate for these limitations, such as birds of a feather flock together, costly signaling, communication, and spatial structure. These hypotheses attempt to explain altruistic behavior from their respective perspectives, but they are not perfect. Therefore, it is necessary to comprehensively consider various theories to understand the complexity of altruistic behavior. Although the repetition-reciprocity hypothesis is not a perfect hypothesis, it remains convincing in explaining altruistic behavior.
In conclusion, altruistic behavior in humans can be explained by various hypotheses. From an evolutionary perspective, such altruistic behavior can contribute directly or indirectly to the survival and prosperity of individuals. Various theories, including the repetition-reciprocity hypothesis, provide important insights into why we help others and form social bonds. Altruistic behavior can be seen not only from a moral perspective, but also as an evolutionary strategy for our survival and prosperity. This understanding can serve as an important guideline for how we should act to create a better society.
