Researchers have found that rats communicate and display dominance by sniffing at each other.

New research from Case Western Reserve University School of Medicine shows that rats use sniffing to display their places in a social hierarchy.

The study, published Friday in the journal Current Biology, was authored by Daniel W. Wesson, PhD, an associate professor of neurosciences at Case Western Reserve’s School of Medicine, and is based on observed and recorded rat interactions. Wesson suggests that the sniffing serves as a “conflict avoidance signal,” alerting less dominant rats to the social hierarchy.

Wessen found that when two rats approach one another, their sniffing patterns communicate their social standing. A rat displaying dominance sniffs more frequently than a rat attempting to display subordinance. If a subordinate rat did not sniff correctly, ceding dominance, the dominant rat was more likely to become aggressive and violent. Wessen likens the sniffing to a dominant ape beating its chest to alert others of its social standing and power.

“These novel and exciting findings show that how one animal sniffs at another greatly matters within their social network,” Wesson told Science Daily. “This sniffing behavior might reflect a common mechanism of communication behavior across many types of animals and in a variety of social contexts.”

Wessen also mentions that sniffing to display dominance may be taking place in many other species, including those with which we are very familiar:

“It is highly likely that our pets use similar communication strategies in front of our eyes each day, but because we do not use this ourselves, it isn’t recognizable as ‘communication.' ”

This research could be used to understand how neurological disorders affect the brain’s handling of social hierarchies, as well as how to conduct appropriate behavior in social situations. Wessen’s team is now looking to study how these behaviors, such as rat hierarchical sniffing, can be disrupted by neurological issues.