From the playground to the office, a key aspect of our social lives involves figuring out who “belongs” and who doesn’t. Our biases lead us — whether we’re aware of it or not — to favor people who belong to our own social group. Scientists theorize that these prevalent in-group biases may give us a competitive advantage against others, especially when important resources are limited.

Psychological scientist Christopher Rodeheffer and his colleagues at Texas Christian University wanted to examine whether resource scarcity might actually lead us to change our definition of who belongs to our social group. Their new research is published in Psychological Science, a journal of the Association for Psychological Science.

One way of defining an in-group is according to outward appearance. Rodeheffer and colleagues hypothesized that people exposed to situations of scarcity would narrow their definition of who “belongs” and would be less likely to categorize a racially ambiguous face as part of their racial in-group.

In their first experiment, the researchers asked 71 White college students to look at captioned pictures that depicted instances in which resources were scarce (e.g., a picture of an empty office with captions about a shortage of good jobs) or abundant (e.g., a picture of a thriving office with captions about there being plenty of good jobs).

Rodeheffer and his colleagues created a series of biracial faces by averaging one White and one Black face using a face-averaging software program. They asked the participants to look at the biracial faces and categorize each face as either Black or White.

The findings showed that students who had looked at pictures depicting scarce resources were more likely to categorize the faces as Black than students who had seen the pictures of abundant resources.

These results were confirmed in a second experiment that used a verbal priming procedure in which the students were primed to think about resource scarcity or abundance by completing analogy problems.

According to the researchers, these findings suggest that “times of economic hardship may limit the inclusiveness of people’s racial in-groups.”

Rodeheffer and his colleagues note that future studies should examine whether the effects of resource availability cues on racial categorization are observed for participants of other races to ensure that the results are applicable across racial groups.

Co-authors on this study include Sarah E. Hill and Charles G. Lord.