The average pooch may know when you’re choosing not to give them treats, new research from Germany suggests. The study found that dogs reacted differently when people withheld food from them intentionally or seemingly by accident, indicating that they could tell the difference. The findings could mean that dogs possess an aspect of cognition often considered unique to humans: the ability to acknowledge the inner workings of others.
In psychology, there’s a concept known as theory of mind. Put simply, it’s our capacity for recognizing that others around us have their own thoughts, perceptions, and mental states and that these can differ from ours. This knowledge can then help us empathize with other people, predict their behavior, and generally understand them better. Though most everyone seems to have a theory of mind, it’s a skill that doesn’t emerge until we reach our toddler years and continues to develop over time.
Humans are generally thought to be the only animals that have a fully developed theory of mind. But some research has suggested that birds and nonhuman primates could have it as well, or at least some of its basic underpinnings. Particularly, these animals seem able to recognize intentionality behind another’s actions.
The researchers behind this latest study, published Tuesday in Scientific Reports, wondered if dogs might pass this simple threshold as well, given their close bond with humans and their ability to respond so deftly to our actions. To test their theory out, they turned to a modified version of a test that’s been used with birds, nonhuman primates, and young humans to measure their ability to read intentionality, known as the “unwilling versus unable” task.
“It’s always hard with non-verbal speech to really know what you’re measuring there. But the nice thing about this task is that it’s actually already established in other species,” study author Britta Schünemann, currently a research scientist at Harvard University, told Gizmodo. “And we had this amazing opportunity with dogs in contrast to chimpanzees and monkeys, in that we could let them approach us—which you can’t do with a chimpanzee, of course.”
The dogs, 51 in total, were separated from their human partners by a glass barrier. But the barrier had a gap that the humans could pass food through, which was demonstrated to the dogs in warm-up tests. The researchers then set up three conditions for all the dogs to endure: one where the humans were about to give food through the gap but changed their mind and deliberately placed it down in front of them; another where the food was about to be passed through the gap but was then “dropped” before it could reach the dog; and a third where the people tried to give food but were deterred by the gap being blocked.
Overall, the dogs responded noticeably differently to the conditions. When the humans pretended to change their mind about giving food, the dogs took longer to approach the barrier than they did when the humans had “accidentally” dropped or couldn’t give the food to them. They also sat or lay down more often and didn’t wag their tails as much—all non-confrontational behaviors that could have been performed to appease the withholding humans.
Schünemann notes that other researchers have been skeptical about the capacity for dogs to attribute intention to others. And there are still other potential explanations for these results, such as the dogs somehow picking up on unintended nonverbal clues by the people that led them to behave the way they did. But given that this test has been used successfully with other animals, Schünemann is confident that the results really do reflect that dogs can tell intention from our actions—a skill that may have very well been essential to the domestication of dogs that began millennia ago.
“Again, we have to be careful here. What we can say, though, is that we have the first evidence that not only chimpanzees and birds but dogs might also have this very basic, but substantial capacity that is part of theory of mind,” she said.
Schünemann normally works with children to understand how the concept of intentionality emerges in people. But she and the other researchers want to study dogs again in the future to better understand how far this ability goes. For now, though, they’re still trying to figure out exactly where to go from here, and she hopes that other scientists will be inspired by their findings to dig further.
She also hopes that her team’s findings will help ordinary people gain a bit more insight into these precious pups. She notes that some people might see dogs as their soulmates, able to completely understand them and their feelings at every level, while others might think of dogs as effectively machines, responding and reacting only to their owner’s actions and commands.
“What we show is that the answer might be somewhere in between— that they are sensitive to humans in a certain way,” she said.