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Are dogs listening, and what are they trying to tell us?

by Manny I. Fox Morone
February 20, 2022 | A version of this story appeared in Volume 100, Issue 7


Word, dog, word

A young kid with long hair laying in grass puts their hand up to the ear of a dog and whispers something.
Credit: Shutterstock
Canine confidant: Your dog may not understand everything you're saying.

Watching some dog owners, you’d think it was human nature to treat the animals like people. We dress them up; we even throw them birthday parties (something this grumpy Newscriptster hasn’t had in a while).

And of course, we talk to them. The question Sophie Jacques and Catherine Reeve posed is: Do they respond to what we’re saying? To gauge the size of a dog’s word inventory, the team had 165 dog owners speak a battery of words and see whether their pets responded to them (Appl. Anim. Behav. Sci. 2022, DOI: 10.1016/j.applanim.2021.105513). Developmental psychologists like Jacques, a professor at Dalhousie University, use a similar method to measure children’s vocabulary during early language development. The scientists thought that a comparison between species could be informative.

The word list the researchers and dog owners put together included objects and common commands that concern the canine kind, like heel, squirrel, and speak—it was a language study, after all. The average dog in the study responded to 89 words, which is around the amount a 1-year-old English-learning human responds to.

“You might think, ‘Oh well, dogs are as intelligent as a 1-year-old.’ But there are very important differences,” Jacques tells Newscripts. Young humans learning English tend to know more nouns than other parts of speech and have a command of more specific object-related concepts, like ball, doll, cookie, or peas. Dogs, however, seem to respond generically to broad categories of objects, like toy or food, she says. Dogs seem to respond to more action words and verbs that they associate with consequences rather than to nouns.

The size of the dogs’ word banks varied quite a bit, but some patterns emerged. Breed types that were developed for work alongside humans, such as herding dogs, and companion breeds, such as chihuahuas, tended to respond to more words than terriers, for example, which were originally bred to chase away vermin, a job that doesn’t require human interaction. Trained working dogs like search-and-rescue dogs and medical-alert dogs also shone in the study, responding to 120 words on average.

So, can your dog understand your lecture on the moral nuances of gnawing on shoes? With 89 words to work with, probably not. But Jacques says a well-calibrated word list could one day be useful to dog trainers. Training a dog to assist a blind person, for example, can take a year or more and cost around $30,000, so using a dog’s word count to weed out those unlikely to make it to the end of training would be handy, if paw-ssible.


A dog putting its ear to a phone that's on the ground and opening its mouth.
Credit: Shutterstock
Here's barking at you: Dogs direct whimpers toward their owners rather than other objects.

Barking orders

Despite the small lexicon, dogs aren’t ignorant to the power of their voice boxes. A new study led by Florence Gaunet and Thierry Legou at France’s National Centre for Scientific Research (CNRS) documented the sounds dogs made when presented with an impossible task—getting their food off a tall shelf—with their owner present (Appl. Anim. Behav. Sci. 2022, DOI: 10.1016/j.applanim.2021.105529).

The researchers recorded videos of dogs yearning to reach the tasty morsel and documented whether the dogs directed each sound toward the food or toward the owner. They then classified the vocalizations into familiar buckets, such as barks, whines, and whimpers, which, Legou tells Newscripts, the team occasionally needed to demonstrate for each other in the lab to make sure everyone was on the same page.

Among other things, they found that dogs directed more whines and whimpers at their owners than they did at the food, and overall the dogs directed about two-thirds of their vocalizations at the owner.

“Dogs are learners,” Gaunet says, but she wouldn’t call their vocalizations language per se. Still, the study shows that dogs don’t think their owners look like chopped liver.

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