What do dogs think when humans bark?
That question was thrust into the spotlight when a hilarious video of an experiment conducted by comedian Rudi Rok and Finnish magician Jose Ahonen went viral on YouTube last week, gaining more than three million views (and, yes, I was gleefully one of those viewers.)
In the experiment, Rok imitated a dog bark while sitting next to different dogs, getting varying reactions from each pooch -- some were aloof while others completely lost it.
"People ask me all the time how dogs react to my barking sounds," Rok wrote on his YouTube page. "So here we go! This is how they respond!"
While the video just may be the best thing you've watched all day, it raises an interesting question: Can a human bark really fool a dog?
I asked Dr. Marc Bekoff, an ethologist at the University of Colorado-Boulder and author of the book Why Dogs Hump and Bees Get Depressed, that question and others about dogs' barks. What follows is a condensed and edited version of the discussion:
When humans try to imitate dog barks, are the dogs fooled or not?
I don't think that dogs are fooled at all. We have a very different vocal system. I think that a particular sound alerts them or arouses them or calms them, depending on context -- where they are or who's around. When I studied coyotes sometimes we howled to see what we could get them to do, and sometimes they'd walk toward us and cock their heads because they knew we weren't coyotes.
Can dogs recognize the barks of other dogs?
This hasn't been studied, but my guess would be that they do make those discriminations. You could look to the wild canids, like coyotes and wolves, where they have group howls, location howls, and it would surprise me if they did not make any kind of individual or group member discrimination.
Do dogs in different countries bark in other languages?
No. As far as I know, the studies haven't been done to show any regional or cultural dialects.
Why do dogs bark?
Dogs bark for lots of different reasons. They might bark to call attention to themselves. They might bark offensively as a threat. They sometimes can bark because it's contagious -- one dog barks, so another dog barks -- so no other reason than social contagion, as we call it. It has been thought that dogs bark to give an indication of where they are. We know that wolves and coyotes, their wild relatives, tend to do that. Dogs also bark when they are really excited or startled.
What are they "saying" when they bark?
It's contextual. So, if a dog is behind another dog, we know sometimes they'll bark to get that dog's attention before they do a play bow, indicating that they want to play. So what they're saying there is, "Look, here I am." If they bark when they are alone it's, once again, a location call. Depending on the kind of bark, it could be an assertive or aggressive vocalization. For that, it's mixed in with a little growl. I always tell people that you have to assess the context in which you hear the bark.
Are barks learned or innate?
Predominately, the sounds are innate. This is a great question, and it's a great question across species. But vocalizations definitely change with age, as people's voices change with age. It could be hormones or sexual maturation but I think a lot of it is just size, just like in humans. Then again, dogs might learn that a particular vocalization gets us to do something they want us to do, like running to the door gets us to put their leashes on and take them for a walk.
Why do dogs howl at firetruck sirens?
People vary in their answers to this, but I think it's because the high-frequency sound may be irritating to dogs. Another idea is that it might be one of those good examples of social contagion, as we call it -- a dog may think he's hearing another howl when he hears the siren.