Watson is focused. Intent. She shifts in her seat slightly, eager and poised. Her eyes dart to me as her eyebrows lift and pinch in deep attention. Then she rests her gaze back on her coveted prize. She lets out a guttural grumble from the back of her throat. Her eyes flick to me, then back to what she wants most in this moment, maybe most in this world: a dirty tennis ball.
“OK!” I say, flinging the ball into the air, and she springs like a trap with eyes wide and ears flopping, leaping headlong for her beloved ball.
Watson, my black Labrador retriever, is 5 years old going on 1, and she has a way of letting me know what she wants. But underneath this daily ritual of fetch with my dog is an entire world of cross-species communication. And recent research suggests that domestication could explain these cooperative interactions and the close bonds between dogs and their humans.
We’ve all heard that communication is the key to any successful relationship. This also applies to our relationships with dogs. But communication can take many forms in the animal kingdom, according to Gabi Venable, a Ph.D. candidate in Duke’s Hare Lab, which studies human and animal cognition. Like many evolutionary anthropologists, Venable and her colleagues at the Hare Lab study many different animals to glimpse the inner workings of their minds to better understand our own.
According to Venable, we often think of language when we think of communication. Animals, however, can communicate in many ways including olfactory (smell), chemical (pheromones), percussive (tapping or thumping), tactile (touch) and vocal (barking, grumbling, howling, etc.).
“Giving hugs or grooming is a sign of coalition,” says Venable. “I am with you.” This brings to mind all the ways in which humans communicate “I am with you” that transcend language and are inherently understood by the person receiving the communication: a knowing smile, a hand on the shoulder, a nod while listening. It turns out the same is true in animals, including our canine companions.
A more nuanced and complex type of communication is cooperative communication – the idea that when we’re communicating it’s “with a shared intent or shared meaning,” as Venable puts it. There’s an expectation that we can work together, or cooperate, to achieve some goal.
While many species, especially humans, are capable of cooperative communication with other members of their species, dog-human relationships are a shining example of interspecies cooperative communication.
For Hannah Salomons, another member of the Hare Lab and the Duke Canine Cognition Center, exploring cognition and communication in animals could tell us how these traits developed in the human mind. Salomons focuses her current research on canines, and she suspects that the evolutionary process of domestication is at the heart of our intuitive interactions with these creatures. According to Salomons, the “self-domestication hypothesis” posits that wild dogs evolved into man’s best friend thanks to dogs that were bold enough to approach humans in order to scavenge food but friendly enough not to pose a threat. There is a similar hypothesis for human behavior that, in a way, humans self-domesticated by choosing companions that were cooperative and social with other humans in their group. So while humans and dogs are not very closely related in the animal kingdom, they may have undergone these similar pressures that gave rise to cooperative communication.
A great example of this cooperation across the species divide is gaze alternation, or looking from the thing you want to the individual who can help you get it. Salomons says this communication behavior is cooperative because a dog is “able to communicate its needs and expect that the other individual is there to cooperate with it.” In contrast, she says, “an animal that has a more competitive type of cognition would never do that because that's showing the other person where the food is and they're going to get it instead of you,” as is common among chimpanzees, for example.
So when my dog Watson dons her look of consternation because she can’t reach her ball and alternates her pleading gaze between me and the ball, she is expecting me to work with her, not against her, to get it. Salomons says, “The fact that the dog is understanding that if it tries to show you where the thing it wants is, and that you might give it to it rather than take it from it, is really huge.”
To better understand the role that domestication plays in the evolution of cooperative communication, she examined these abilities across canine species. In a 2021 study, Salomons tested undomesticated wolf puppies from a rescue and rehabilitation center in Minnesota and domesticated dog puppies on their ability to use human gestures like pointing and eye gaze.
Salomons and her team selected these gestures because they are deeply ingrained in human cooperative communication. Human babies undergo a sort of “revolution” at around 9 to 12 months old in which their cognitive abilities to use and interpret basic social communication cues, like gaze and pointing, develop, or “come online,” as Salomons puts it.
The seemingly simple gesture of pointing is actually a precursor to verbal communication, and it involves several complex cognitive tasks that we as humans may take for granted. First, pointing indicates that we are referring to something other than the pointing hand itself. Second, pointing can indicate different intentions, like telling someone the object’s location, asking for the object, or just making someone aware of it. Some research explores whether babies can use pointing even younger and under what conditions.
As for dogs, Salomon’s study’s findings suggest that dog puppies’ flexibility and use of gestures like pointing are “human-like” compared to wolves and that, despite the study’s wolf puppies being raised with far more human contact than the dog puppies during the experimental period, dog puppies out-performed wolf puppies in interpreting human gestures. The reason, Salomons suggests, is that dogs underwent domestication over tens of thousands of years and wolves did not.
While the field of evolutionary anthropology hasn’t reached a consensus about the origins of cooperative communication in all animals, Salomons says that her recent comparative study between dog puppies and wolf puppies supports the hypothesis that domestication led to dog-human cooperative communication.
Given this profound ability to communicate with shared meaning and intent, dogs and humans are able to form close bonds perhaps unlike those we share with other domesticated animals.
“You don't really see people bringing their cats to a barbecue because the cat wouldn't enjoy it,” Salomons points out.
Research into domestication is expanding, including deeper dives into the genetics underlying dog cognition and research into close cousins such as foxes and dingoes, and Salomons is excited about the future of the field and our understanding of this interspecies connection.
“Dogs are primed to want to communicate and understand us,” Salomons says. Working with them naturally aligns with how they think and interact.
Now, when Watson stares up at me ponderously, I see a universe of evolution in her expressive, dark brown eyes empowering our uncanny connection that tells me she’s ready for a new game of fetch.
K. Lou Ward is a science writer whose work spans reporting, essays and poetry. They trained in the Master of Arts in Science Writing program at Johns Hopkins University and hold a B.S. in Biology from Duke.