Why do lions chase gazelles that run away? We examine the mechanism of trust formation in animal and human societies through expensive signaling theory.
In Africa, a lion begins hunting a gazelle to catch it. However, one gazelle does not flee but jumps up and down in place. The lion does not catch this gazelle that does not flee but instead chases after another gazelle that is fleeing at full speed. Why did this happen?
At first glance, this seems incomprehensible.
From the gazelle’s perspective, it is common sense to run away at full speed when a lion is chasing it, and from the lion’s perspective, it is common sense to catch a gazelle that does not run away rather than one that is running at full speed. However, if we examine this scene more closely from the animals’ perspectives, we can find a reason that makes this situation understandable. Hunting is extremely physically demanding for both the hunter and the prey.
Therefore, when a lion begins a hunt, it must maximize its chances of success. Chasing the slowest gazelle in a herd allows the lion to conserve energy and increase its chances of success. Gazelles, not knowing which lion is chasing them, must all flee initially. However, if a gazelle realizes that a lion is not chasing it, it can reduce the energy expended in fleeing.
If the slowest gazelle also reveals its identity through its behavior, both the lion and the gazelle can minimize their energy expenditure. However, from the lion’s perspective, there is no practical way to identify the slowest gazelle. The fastest gazelle will perform actions that the slower gazelles cannot imitate in order to prove its speed.
This is how gazelles escape the lion’s target, and that behavior is jumping up and down. The reason jumping up and down proves one’s speed is that by performing a dangerous action even though there is a predator targeting them right in front of them, it instills in the lion the belief that “this gazelle is a fast gazelle.” Furthermore, this behavior is dangerous, so a slow gazelle would never attempt it with a predator right in front of it.
The leaping behavior is a signal that shows how well the gazelle can run. Since this signal cannot be sent by just anyone, it is called a “costly signal.” Another example of a “costly signal” can be found in another animal.
In the case of peacocks, only males have elegant tail feathers. However, these feathers are too large and heavy to carry around, and they are easily noticed by predators, making them dangerous. Despite this, peacocks carry these feathers because they are considered sexually attractive, giving them an advantage in finding a mate. Why are these feathers considered sexually attractive? The reason is that if a peacock can survive despite having such cumbersome feathers, it demonstrates its ability. A peacock without such ability would have already died. Therefore, the existence of these feathers serves as an expensive signal. The more expensive the signal, the more the recipient trusts it.
Humans also send signals to demonstrate their abilities. Let’s look at a few examples of valuable signals that people send.
In gangster movies, there is a common scene where two gangsters, before fighting, hit their heads with beer bottles, and another person hits his head with a wooden stick, breaking it, which seems like an incomprehensible action at first glance.
However, this action has the same effect as the frog’s leap. Someone with no inner strength or weakness would not be able to perform this action because it would cause significant harm to themselves. This action, which only the strong can perform, serves as an expensive signal to demonstrate their strength to others.
People buy luxury cars, clothes, and watches to show off their wealth. If these items are so expensive that no one can even imitate them, they become expensive signals. The more expensive these items are, the more effective the expensive signal will be.
Another example of people’s actions to show off their wealth is the Potlatch festival of the Kwakiutl tribe.
In the northwestern region of the North American continent, there is an Indian tribe called the Kwakiutl. They hold a unique festival called Potlatch, where several villages come together to celebrate. The leader of the village hosting the festival gives enormous gifts to the leaders of other villages and to the people of other villages. At the end of the festival, participants throw their possessions into the fire, starting with less valuable items and eventually burning even their own homes. This seemingly absurd behavior is interpreted as an incredibly expensive signal demonstrating one’s immense power and wealth.
Signals must, of course, be trustworthy, and to be trustworthy, they cannot be sent by just anyone; only those with specific abilities can send such signals. In short, sending such signals comes at a cost. Those without the ability to send such signals will not do so because the cost of sending the signal outweighs the benefits gained from it. On the other hand, those with the ability to send such signals will do so because the benefits gained from sending the signal outweigh the cost. Therefore, those receiving the signal will believe that the sender possesses the ability and trust the signal.
This signaling theory can also be applied to explain human behavior. For example, employees may volunteer for overtime or take on challenging projects to demonstrate their performance or ability at work. These actions serve as costly signals to their superiors and colleagues, demonstrating their ability and dedication. Such efforts and dedication can earn much more trust than simply stating them verbally.
Examples of costly signaling can also be found in academia. Students who strive to attend higher education institutions, maintain high grades, and participate in various competitions are demonstrating their intellectual abilities and the results of their efforts. These signals leave a strong impression on college admissions officers and future employers, making them more likely to trust the student’s abilities.
Finally, expensive signaling plays an important role in social relationships. For example, at weddings or important social events, people wear expensive clothing and accessories and host lavish parties to showcase their social status and wealth. These signals are not merely external displays but also serve as a way to demonstrate that one is trustworthy.
