Can altruistic behavior in organisms be fully explained by the kin selection hypothesis?

Selfishness stemming from an organism’s reproductive instinct can explain altruistic behavior in kinship relationships, but not non-kin altruism. In addition to the kin selection hypothesis, other hypotheses, such as reciprocal altruism, suggest reasons for altruistic behavior and provide an important basis for understanding the behavior of living things.

 

All living things have a reproductive instinct to leave offspring. This instinct has been strengthened by natural selection as organisms have evolved over time. Organisms fulfill this instinct in a variety of ways. Competitive courtship behaviors during the breeding season and dedicated parenting behaviors to care for offspring are all manifestations of this instinct. It’s not just about preserving the species, it’s a strategy at the gene level to spread as many of their genes as possible.
This instinct drives organisms to be maternal and devote themselves to the stable growth of their offspring. This is because some of their genes are passed on to their offspring, meaning that maternal love is driven by self-interest in spreading their genes through their offspring. This maternal behavior is observed in a wide variety of animals, but it’s especially prominent in human societies. In humans, maternal love is more than just a biological instinct; it has evolved into a complex emotion that combines cultural and social factors. Maternal love extends beyond protecting and nurturing one’s children to constantly striving for their social success and happiness.
But even the most selfish creatures can sometimes perform selfless acts, sacrificing themselves for the sake of another individual. Humans are no exception. Since time immemorial, many people have lived in clusters of relatives, and it’s not just their offspring that they care for. Altruistic behavior in human society isn’t just a biological instinct, but the result of complex social relationships and moral values. So, why does altruistic behavior toward non-offspring occur when it doesn’t seem to have much to do with the reproductive instinct?
There are several hypotheses to explain this, including the kin selection hypothesis. First of all, kinship means “ties by common blood,” or in other words, descendants of the same ancestor. This hypothesis explains that altruistic behavior is driven by kinship, which means that people are willing to sacrifice themselves if it will benefit their kin. Because kin share some of the genes they inherited from their parents, offspring are not the only ones who can spread their genes. Therefore, they are acting on their reproductive instincts by helping other individuals in which their genes are present.
It’s important to clarify here the difference between a gene and an individual. Genes exist in many individuals because they can create genes exactly like themselves, but individuals cannot create individuals exactly like themselves, only similar individuals. With this in mind, we can see that genes act selfishly to reproduce themselves, while individuals act altruistically to reproduce their genes.
What are some examples of altruistic behaviors in living things that are explained by kin selection? Starting with humans, notice that we have the word “clan”. We used to live in clans, although less so now. The Parks were the Parks, the Kims were the Kims, the Yi’s were the Yi’s, and so on, helping each other through hardships and enduring hardships together. It’s something we take for granted in our culture, but if you try to find the origins of clan culture, it’s hard to find anything other than sharing the same genes.
Let’s look at other animals. Ants are a classic example of animals that live in groups of countless numbers, but each ant has its own role and works diligently for the group. The majority of them are worker ants, who do the actual work. They work hard for the queen ant. The queen is responsible for the reproduction of the colony. The reason why worker ants, as well as ants in other roles, are so devoted to a single queen ant is because they come from the same parents, meaning they share the same genes.
However, there are areas where this hypothesis fails to explain. In human society, we often perform altruistic acts even for people who are not related to us by blood. For example, our willingness to donate money or volunteer for strangers or help others in danger is independent of blood ties. Altruistic behavior beyond kinship is also observed among many species of animals. This suggests that many animals, not just humans, have complex social structures.
However, this hypothesis is not perfect. Humans don’t just lend a helping hand to their own kin. The people who make monthly donations to African children are not related to them. The person who begs for money on the subway and the person who gives it to them are not related. People who give their services without expecting anything in return are not related to the people who receive them. To give an extreme example, an elephant helps a driver whose car has fallen into a ditch and is in trouble. The elephant and the driver are also not related.
As you can see, the kin selection hypothesis is not an appropriate hypothesis to explain altruistic behavior between unrelated individuals. However, there are other hypotheses that explain altruistic behavior. For example, the Reciprocal Altruism hypothesis explains behaviors in which individuals help each other even when they are not directly related to each other to create a favorable environment for survival. This is particularly strong in human societies, where interactions are based on social bonds and trust.
As we’ve seen, the kin selection hypothesis explains altruistic behavior among kin as occurring because they share the same genes and therefore want to spread those genes. It does a good job of explaining the altruistic behavior of individuals in close-knit groups, which is common in nature, but it doesn’t explain the altruistic behavior of unrelated individuals, which is also common. In that sense, it’s not a perfect theory to explain altruistic behavior, so it remains a hypothesis. However, it does provide an important foundation for understanding the behavior of living things and offers an interesting perspective on how life has evolved with altruistic behavior.