Getting to Grips with Groups: Cristina Moya

By Ashley Serpa – Why do humans form social groups? What do group boundaries mean? Assistant Professor of Anthropology Cristina Moya examines the symbolic and linguistic markers humans use to determine group boundaries, and investigates why they encourage certain behaviors.

Intergroup relations are a significant facet of human interaction. “Group boundaries and the ways they affect our social interactions feel so natural to us,” says Moya, an evolutionary anthropologist who earned her PhD from UCLA in 2012 and joined the faculty at UC Davis in 2016. “It makes it difficult for us to recognize the diverse ways that group boundaries culturally evolve in human societies and what they’re used for.”

Most markers that help define group boundaries act as signals that help establish group membership. While the concept of group boundaries may appear exclusionary, Moya views it as more complex. “I have tried to push the field away from thinking that what it means to be an in-group and out-group member is clearly defined,” she says. “You can have in-groups and out-groups for different purposes. You can have group boundaries that are relevant for categorization, so that people can predict other’s behavior based on their category membership, but it doesn’t necessarily mean they hate out-group members or want to go to war with them.”

Mapping boundaries

In other cases, group boundary markers can help people determine with whom to trade and form alliances. One of Moya’s goals is to “differentiate the roles and purposes of group boundaries, recognizing that ethnic phenomena are not just about intergroup hatred, and that functions such as stereotyping, in-group cooperation, and intergroup hostilities do not always map onto a single boundary.”

So, can we trace the evolution of group markers over time? Yes—to an extent. “There are two dimensions at least that we can trace. One of them is how the things that are used for marking the boundary change through time and the other one is what are the consequences of being within or outside of a certain boundary.” In other words, a marker may change or remain the same, but in either case, its implications can change. 

Comparing the roles of sartorial markers

In a June 2016 Current Anthropology article, Moya and her co-author Robert Boyd argue that “we must take seriously the role of cultural similarity in delineating certain category boundaries if we are to understand the origins and development of ethnic stereotyping.” To that end, they examine and compare the role of symbolic markers—specifically, stylistic ones related to clothing—among children and adults in the urban U.S. and rural Peru.

Humans symbolically mark group identities and categorize others according to these markers, the article explains. It is possible that humans have evolved to expect some of these markers, like clothing or other accoutrements, to have social meaning. “We thought it was an interesting comparison to look at what children brought to this task that might be similar in the two different places and see how it might diverge as they became adults.”

In the end, it proved unexpectedly difficult to find clear patterns that were comparable across the two sites. Whereas the Peruvian children “really paid attention to sartorial markers, and even more so than their parents did,” the American children “really didn’t care about the sartorial markers at all.”

Proceeding with caution

What’s the explanation? “One possibility is that the social environments of children are actually more different than those of adults in these two contexts. However, we also think that this sample of children in the U.S. versus the adults in the U.S. might not represent members of the same communities like they did in Peru. The U.S children were from a lab school environment at UCLA that represents a relatively privileged subset of Los Angeles, while the [adults] were undergraduates at UCLA—not the same demographic.”

This, Moya concedes, was a cautionary tale. “We had two sites, the same kind of protocol that was sensitive to the contexts in each site. And still, in the end, the interpretation of the results is very difficult in terms of how these kinds of patterns reflect different genetic and cultural pathways to learning about the world or to understanding social group boundaries.”

Tracing changes in perception

Moya is currently revising for publication a manuscript co-authored with Annie E. Wertz. In it, the authors consider how genetic and cultural evolution work together to influence cognitive mechanisms, using group boundaries as the subject of analysis. 

As this research developed, Moya was guided in new directions. “The more time I spend on this question, the less convinced I am that we can make much headway on this,” she says. “Most evolutionary social scientists agree that humans have genetically evolved to be language learners. But how that interfaces with our thinking that language boundaries, and the way that other people speak, are socially meaningful is really hard to disentangle.”

Moya has new projects underway that seek to understand why certain group boundaries are thought of as fixed, while others are not. Taking a meta-analysis approach, she is pulling already-collected data from different projects that look at children and adults across multiple sites.

The goal? “To see how perceptions of those [group boundaries] develop with age and how they are variable or similar across different contexts. And then to try to understand what features of those group boundaries might correspond to beliefs that the group boundary is more fixed.”

A chicken-and-cow situation

Preliminary results reveal “diversification of beliefs about social group boundaries from childhood to adulthood.” The data shows variability among children that grows even more in adulthood as they learn how their local group boundaries are defined.

We must take seriously the role of cultural similarity in delineating certain category boundaries if we are to understand the origins and development of ethnic stereotyping.


Interestingly, when species boundaries come into play, the results flip. “If you ask someone whether a chicken raised by a cow will grow up to be a chicken or a cow, nearly everybody in adulthood says it’s going to be a chicken. The children show more variation because they haven’t yet come to that conclusion that species boundaries are fixed, a belief that seems to develop reliably by adulthood across cultures.”

Moya concludes that this kind of project, working with this kind of data, is best suited to looking at how cross-cultural variation changes with age, and what such change can tell us about human learning processes and biases. 

Adding depth through collaboration

Since joining the faculty at UC Davis in 2016, Moya has appreciated and benefitted from a spirit of collaboration, both within her department and beyond. She believes that collaboration between archaeologists and historians is crucial to understanding the evolution of symbolic markers and their implications.

Meanwhile, work by Moya’s colleague Randy Haas, a fellow assistant professor of anthropology, has been instrumental in her own research. By uncovering some of the earliest cranial modification in the Andes, Haas has “added a time depth to our understanding of the times and contexts where this group marker was used. We have had several conversations now trying to understand what this kind of marker can honestly signal about someone to try to get a sense of what it could have been used for.”

Breaking new ground

In terms of the larger evolutionary social science discipline, Moya hopes to add complexity to the understanding of group psychology and its different features. In particular, she says, we should not “just blindly assume that the group psychology we have is the same psychology that chimpanzees have.” There is an important cross-cultural element to this work, especially when considering the role of language boundaries—something uniquely human.

“They’re not the only way that boundaries matter, but it is something that happens recurrently cross-culturally. Striking the middle ground between really detailed, context-specific case studies, and generalizing our understanding of what group boundaries mean in human societies, will be one of my goals.” 

Learn more about Cristina Moya.