When social psychologists and behavioral scientists talk about social norms, they are usually less interested in specific cultural practices (like handshakes) than they are in broad tendencies in human behavior. A lot of research in this area has explored normative influence on people’s actions—in other words, how people’s behavior is influenced by the behavior of others around them. These studies have shown that people are often swayed by simply observing how others act, even when they haven’t been told to act in a specific way.
One study, conducted by Elliot Aronson and Michael O’Leary in the 1980s, investigated whether social norms affected students’ water consumption. At the time, Aronson and O’Leary were at the University of California at Santa Cruz, where drought is a recurrent problem. The university had put signage in campus shower rooms asking students to conserve water by turning off the shower while they soaped up. Despite the signs, only 6% of students were following this request.1 So the researchers recruited a few male students to participate in an experiment.
One student, the role model, entered the shower room, turned on the shower, and waited until he heard somebody else come in. At that point, the role model turned off the shower to soap up, as the sign instructed. When the role model finished his shower and exited the room, another student, the observer, would enter, to see whether or not the other student had followed suit. The researchers found that 49% of students followed the behavior of the role model—and when a second role model was added, 67% conformed.2
Beyond the general tendency for people to act in the same way others do, there are a few specific norms that often guide people’s behavior (at least in Western societies, where most of the relevant research has been conducted), such as the norm of reciprocity—the fact that we usually feel compelled to return the favor when somebody else does something nice for us.
In one experiment demonstrating the power of reciprocity, participants were told that the study was about “cognitive perceptual skills,” and were given various tasks to complete. At some point during the experiment, a confederate—somebody posing as a participant who was actually in on the experiment—got up to use the restroom. For half of the participants, she came back with a bottle of water, as a favor. Later, the confederate asked the participant if they would be willing to complete a survey for a research project, giving them a copy of the survey and telling them where they could go to drop it off. Participants who had received a water bottle from the confederate were significantly more likely to fill out the survey, returning the favor.3
It’s clear that social norms can have a strong influence on our behavior. But why is this the case? In situations where we’re less familiar with what’s going on, and we feel less certain about how we’re supposed to act, we might follow the behaviors of others simply because it’s our best bet. But most of the time, our adherence to social norms has more to do with evolutionary pressures, and with our desire to see ourselves in a certain light.
We have evolved to crave acceptance
One of the strongest drivers of human behavior is our need for belonging. Humans are social creatures, and there’s an important reason why: in prehistoric times, there was no other way to survive. In a harsh and unforgiving ancient environment, it was crucial to maintain good relationships with others, to be part of a collective. Operating as a group allowed humans to hunt larger animals, better defend themselves from predators or enemies, share food and resources with one another, and more. The individuals who survived long enough to pass on their genes to the next generation were most likely those who had close ties with the rest of their tribute.4
In the modern age, we may no longer need the help of our comrades to bring down a woolly mammoth, but our brains still retain the neural hardwiring of our ancestors. The need for belonging, and the desire for closeness with others, is considered to be a fundamental human motivation.4 Social connection is so integral to our existence that a lack of it is detrimental to our physical health: in one meta-analysis that reviewed the findings of 148 studies on social isolation and mortality, researchers found that people strong social relationships had a 50% increased likelihood of survival.5
By following social norms, we avoid ruffling any feathers and risking rejection by others. Some specific norms, such as the norm of reciprocity, also seem to exist specifically to enhance our relationships with other people, and to create a sense of unity.
We want to protect our self-concept
Another fundamental human need, alongside belongingness, is the need to maintain a positive image of ourselves. One way to do this is to keep our behavior consistent with the norms and values that we gradually internalize as we grow up.
As we’re maturing, we learn the norms of our society both through observation and through direct reinforcement: certain behaviors are rewarded, while others are punished. By the time we reach adulthood, most of us have a firm set of values, and a particular idea of how a “good person” behaves. And since we all want to see ourselves as good people, we often hold ourselves to the standards set by our personal norms—the norms we’ve internalized—in order to protect our own self-concept.6
There is experimental evidence to back up this idea. In a 1991 study, researchers had participants fill out a questionnaire that assessed how strong their attitudes were about littering. They then had them complete a task while researchers monitored their heart rate and their skin conductance response (how much they were sweating), which required putting a special paste on one of their palms. While participants did the tasks, they were also looking at a TV monitor, which either showed an image of themselves doing the task (the “internal focus” group), or a series of geometric shapes (the “external focus” group).
After the task was finished, the participants were told they could leave, and they were given a piece of paper towel to remove the paste from their hands. What the participants didn’t realize is that the researchers would be checking to see whether they littered, by dropping the paper towel in the stairwell outside the experiment room. The results showed that, for people who had a strong personal norm against littering, being in the internal focus condition significantly decreased the amount of littering, whereas for people who didn’t really care about litter to begin with, it didn’t have much of an effect.8 Why? The researchers argue that seeing themselves on a TV screen made people more aware of their self-concepts, and made them more likely to act in a way that was consistent with their internalized norms and values.