Dogs are vocal animals, and most of us have heard a variety of canine sounds, from growls to barks, whines, and whimpers. But how good are we at determining the emotional state of a dog when she or he is growling? A new and very important study by Hungarian researchers T. Faragó, N. Takács, Á. Miklósi, and P. Pongrácz called "Dog growls express various contextual and affective content for human listeners" shows we're pretty good at assigning context and emotional state to different growls, and that women are better than men at doing so.
The abstract for this study reads as follows:
"Vocal expressions of emotions follow simple rules to encode the inner state of the caller into acoustic parameters, not just within species, but also in cross-species communication. Humans use these structural rules to attribute emotions to dog vocalizations, especially to barks, which match with their contexts. In contrast, humans were found to be unable to differentiate between playful and threatening growls, probably because single growls' aggression level was assessed based on acoustic size cues.
"To resolve this contradiction, we played back natural growl bouts from three social contexts (food guarding, threatening and playing) to humans, who had to rate the emotional load and guess the context of the playbacks. Listeners attributed emotions to growls according to their social contexts. Within threatening and playful contexts, bouts with shorter, slower pulsing growls and showing smaller apparent body size were rated to be less aggressive and fearful, but more playful and happy. Participants associated the correct contexts with the growls above chance.
"Moreover, women and participants experienced with dogs scored higher in this task. Our results indicate that dogs may communicate honestly their size and inner state in a serious contest situation, while manipulatively in more uncertain defensive and playful contexts."
An excellent summary of this study can be found in an essay by Nicola Davis called "Barking up the right tree: study shows we can understand dog growls." She summarizes the results as follows:
"Participants were able to correctly classify 81 percent of play growls, 60 percent of the food growls, and 50 percent of the threatening growls, with further analysis revealing that often the latter two were confused. What’s more, the team found that women, and dog owners of either sex, were better at the task."
Women might be better than men because they have higher emotional sensitivity. The researchers' own conclusion for this important study reads:
"Our findings emphasize that although emotions may have common acoustic encoding, deciphering of the contextual information of another species' vocal behavior also involves learning. This phenomenon has already been seen in the case of assessing the emotions in species with different levels of familiarity to human listeners, but now we also found evidence for it in less common types of dog vocalizations.
"Our results may also indicate that dogs communicate honestly their size and inner state in serious contest situations where confrontation would be costly, such as during guarding of their food from another dog. At the same time, in contexts with assumedly more uncertain inner states, such as in play or when threatened by a stranger, they may manipulate certain key parameters in their growls for an exaggerated aggressive and playful expression. According to our results, adult humans seem to understand and respond accordingly to this acoustic information during cross-species interactions with dogs."
The importance of becoming dog literate
The results of this research are significant: If humans are good at understanding what dogs are saying and feeling when they're growling, it could help us better understand what they're doing or likely to do in a given situation. As University of Sussex (UK) animal communication expert Holly Root-Gutteridge notes, "Learning about these differences may help in reducing dog aggression towards humans, as well as improving dogs’ behavior, as we understand better when a threat is real versus playful.”
It's highly likely that dogs understand what they're saying to one another; this might be one reason why play so rarely escalates into real aggression, even when it sounds to us like things are getting out of hand. For example, Melissa Shyan and her colleagues discovered that fewer than 0.5 percent of play fights in dogs developed into conflict, and only half of these were clearly aggressive encounters. (See "Butts and Noses: Secrets and Lessons from Dog Parks" and "Dominance in Free-Ranging Dogs: Age and Social Tolerance.")
Decoding what dogs are saying and feeling—accurately reading their moods—is necessary if we're to live harmoniously together. It's also essential so that dog-dog encounters will be as amiable as they can be. All we have to do is pay careful attention, and it's really a lot of fun to become dog literate and get to know the amazing being(s) with whom we share our home.
Marc Bekoff’s latest books are Jasper’s Story: Saving Moon Bears (with Jill Robinson); Ignoring Nature No More: The Case for Compassionate Conservation; Why Dogs Hump and Bees Get Depressed: The Fascinating Science of Animal Intelligence, Emotions, Friendship, and Conservation; Rewilding Our Hearts: Building Pathways of Compassion and Coexistence; The Jane Effect: Celebrating Jane Goodall (edited with Dale Peterson); and The Animals’ Agenda: Freedom, Compassion, and Coexistence in the Human Age (with Jessica Pierce). Canine Confidential: An Insider’s Guide to the Best Lives For Dogs and Us will be published in early 2018. Marc's homepage is marcbekoff.com.