Posted Date: May 16, 2013
A study has demonstrated how sniffing, a common behavior in dogs and other animals, also serves as a method of communication. By Claudia Bensimoun.
A study has gained insight into how sniffing, a common behavior in dogs, cats, and other animals, also serves as a method of communication. This fundamental discovery will help scientists identify brain regions critical for interpreting communication cues and what brain malfunctions may cause some complex social disorders.
Sniffing is a specialized respiratory behavior that is essential for the acquisition of odors. No measures of sniffing among interacting animals are available. Not all sniffing is aimed at gathering scents. Some sniffing seems to be aimed at transmitting messages such as "I'm pack leader," or "Stay away."
The research by Dr. Daniel W. Wesson, PhD, of Case Western Reserve University School of Medicine and his team found that rats sniff each other to signal a social hierarchy and to prevent aggressive behavior. Although researchers have long observed how animals vigorously sniff when they interact, a habit that is usually passed off as simply smelling each other, these new findings represent the first new form of communication behavior in rats since it was first discovered in the 1970s that they communicate through vocal ultrasonic frequencies. This research provides the basis for understanding how neurological disorders may impact the brain's ability to conduct normal, appropriate social behaviors. "These novel and exciting findings show that how one animal sniffs another greatly matters within their social network. This sniffing behavior might reflect a common mechanism of communication behavior across many types of animals and in a variety of social contexts. 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," says Wesson.
In the study, Wesson used wireless methods to record and observe rats as they interacted. He found that, when two rats approach each other, one communicates dominance by sniffing more often, while the subordinate signals its role by sniffing less. He found that if the subordinate didn't do so, the dominant rat was more likely to become aggressive with the other.
Rats and other animals, like dogs, give off odors from their flanks, face and anogenital region. Dr. Wesson, PhD, of Case Western Reserve University, School of Medicine found that when rats sniffed each other's flanks, their sniffing increased. By the time when the rats were sniffing each other's faces, their behavior depended on whether they were socially dominant or subordinate. Higher-ranking rats tended to speed up their sniffing and lower-ranked rats tended to slow down their own sniffing response. Wesson found that when subordinate rats did not decrease their sniffing, the dominant rat would pick a fight. Sniffing is a form of communication in rats, but only sniffing towards the face. Face sniffing is an incredibly vulnerable position for an animal to be in.
Wesson theorized that the dominant rat was displaying a "conflict avoidance signal," similar to a large monkey walking into a room and banging its chest. In response, the subordinate animal might cower and look away, or in the case of the rats, decrease its sniffing.
Wesson's laboratory intends to use these findings to better understand how certain behaviors go awry. The hope is to learn whether this form of communication can help explain how the brain controls complex social behaviors and how these neural centers might inappropriately deal with social cues.
Wesson's research is supported by grants from the National Science Foundation, the Mount Sinai Health Care Foundation, and the University Hospitals Case Medical Center Spitz Brain Health Fund.
Claudia Bensimoun is a freelance writer in West Palm Beach.