In the animal kingdom, species often interact and behave according to a social hierarchy. Within the group, social messages are communicated in a wide variety of subtle ways. Dominant animals often exhibit aggressive or overly assertive behavior. They typically hunt and eat first, and they eat more. Less dominant animals wait to eat, eat less, and often show other signs of submission.

Humans are not so different. We also operate according to a social hierarchy in which there are dominant and nondominant members. The next time you’re wondering who’s who, just ask the wee one in the bunch. According to new research published in “Cognition”, babies as young as 17 months can identify the dominant individuals in social situations.

“I think these results are really interesting and provocative,” says Kristin Shutts, associate professor of psychology and member of the Social Kids Lab at the University of Wisconsin. “There is a growing body of evidence suggesting that very young children – even infants – can attend to and understand cues regarding which individuals are more dominant or powerful than others.”

The research, led by University of Washington psychology professor Jessica Sommerville and graduate student Elizabeth Enright, built on previous evidence that infants have an understanding of dominance, as well as evidence that infants expect equal distribution of resources.

It was unknown, however, whether infants would combine this information. After learning that someone was dominant, would infants still expect equality or would they expect the dominant person to receive more?

To test this question, the researches ran five studies with 80 children between 17 and 18 months old (16 toddlers per study). In each study, they measured toddlers’ looking time. Participants were shown one video repeatedly until they habituated (became bored and looked less than they initially had been looking) and then they were shown new test videos. In these paradigms, infants and toddlers typically look longer at what they find unexpected or out of the ordinary.

Adults behave in the same manner. For example, a magic trick or a car accident catch and hold our attention because they’re unexpected. When toddlers watched videos in which non-dominant characters in the videos received rewards, which was not expected, they looked for about seven seconds longer than normal. Measuring a baby’s “looking time” is a common metric used in studies of cognition and comprehension in infants, according to the researchers.

“This tells us that babies are sorting through things at a higher level than we thought. They’re attending to and taking into consideration fairly sophisticated concepts,” Sommerville said in a press release. “If, early on, you see that someone who is more dominant gets more stuff, and as adults, we see that and say that’s how the world is, it might be because these links are present early in development.”

What is it about the social hierarchy that makes it so naturally ingrained that even an infant recognizes it? “This is still an open question, and there might be a variety of different reasons for why toddlers already recognize social hierarchies,” said Enright. “One reason might be that they see social hierarchies all the time. For instance, they might see an older sibling able to get what they want and exert dominance over a younger sibling. They might see a parent reinforce rules over themselves and younger siblings.”

Additionally, Enright explains, social hierarchies are not unique to humans. Many other species not only have social hierarchies, but also recognize social hierarchies. So it may not be surprising that these hierarchies could be ingrained and recognized early.

Understanding social hierarchies can actually aid child development. Parents set rules and are in charge of their children, teachers have authority over their classrooms, older children can make decisions over younger children, and the list goes on and on. As a toddler and young child, it is beneficial to recognize these social hierarchies in order to understand the social world.

When these children are in daycare and more structured settings, says Enright, knowing who’s in charge is important. Similarly, among peers it is beneficial to recognize social status and notice the potential consequences of status (the “boss” of the playground might get more resources, like toys and snacks).

This early understanding raises some interesting questions: “Have children of this age already observed and learned from their environment that people who control one resource are likely to have or receive further resources? Or do children come into the world with an expectation that possessing better or more resources is a key part of being in charge?” Shutts asks.

We don’t currently have the answers. Additional research with younger infants, with infants in different cultural contexts, and with experiments that present other kinds of dominance information will be key to figuring this out.

“These are early days when it comes to understanding what young children perceive and understand about social hierarchies,” says Shutts. “But this new set of studies is an important piece of the puzzle.”