A new study found that dogs often address their humans using a fairly straightforward list of gestures.
It's pretty widely accepted that dogs can't talk (besides Air Bud, of course). That doesn't mean they don't try to communicate with their owners, though.
Using intentional gestures to communicate a request is what scientists call "referential signaling." This phenomenon is different from normal movement because the gestures don't serve a practical purpose — they're just symbolic — and they're repeated until the request is granted. For example, a dog might press his nose against your knee until he gets a treat, for instance, but once he has the treat, he'll stop. And yes — dogs are kind of freeloaders in that they only ever address you when they want something. Science has yet to find a canine referential signal for "good human," much less "Let me tell you about my day at the dog park."
While this might be old news to dog owners, it's new to scientific research. Hannah K. Worsley and Sean J. O'Hara of the University of Salford in the UK discovered it by combing through hundreds of videos of 37 dogs interacting with their owners. They found that the dogs addressed their owners with 19 distinct referential signals, which included rolling over, jumping up and down, and the seated front-paw hover. (These may sound like basketball plays, but think of them more like the dog alphabet.) Sometimes, dogs used a single gesture on its own; other times, they combined a few gestures to get their request across. Their most common requests were for food and water, toys, scratches, and opening a door.
Referential signaling may be newly associated with dogs, but in and of itself, it isn't new. It's well known that great apes use it to communicate with each other. Human babies use it, too, to communicate with their parents before they can talk. We also already know that it's not exclusive to primates: Recently, scientists discovered that ravens do it too. However, domesticated dogs are the first animals scientists have found that use referential signaling to address another species.!
