We all know that dogs can sense our emotions, whether happy, sad or angry, but now researchers have found that they can also tell when you're lying, and will stop following the cues of someone they deem untrustworthy.
Researchers led by Akiko Takaoka from Kyoto University in Japan figured this out by using the old 'point and fetch' trick - a human points at the location of something, like a ball, a stick, or some food, and the dog runs off to find it. They wanted to figure out if dogs were just blindly following these cues, or if they were adjusting their behaviour based on how reliable they perceived the person giving the cues to be. And if they didn't perceive this person as being reliable, how quickly would they learn to mistrust and disobey the humans who pointed in the wrong direction?
Working with 34 dogs, the team went through three rounds of pointing. The first round involved truthfully pointing out to the dogs where their treats and toys were hidden in a container. In the second round, after showing the dogs what's in the container, they pointed out the location again, but this time, it was a trick - the container was empty. In the third round, the team pointed to the location of the box, which was filled with treats again.
They found that the dogs were following the age-old adage, "Fool me once, shame on you, fool me twice, shame on me," because by round three, many of them were done believing the actions of the pointing volunteers.
A second experiment was performed in exactly the same way as the first one, except the person was replaced by an entirely new one. The dogs happily started the process all over again, and were fully open to trusting their new 'friend'. "That suggests, says Takaoka, that the dogs could use their experience of the experimenter to assess whether they were a reliable guide," Melissa Hogenboom writes for BBC News writes for BBC News. "After these rounds, a new experimenter replicated the first round. Once again, the dogs followed this new person with interest."
What's going on here, the researchers report in the journal Animal Cognition, is that the dogs were 'devaluing' the reliability of the human when they experienced their lies. "Dogs have more sophisticated social intelligence than we thought," Takaoka told Hogenboom. "This social intelligence evolved selectively in their long life history with humans."
The experiment reaffirms what we know about the nature of dogs - they love routine, but they also love new things. In round one, they learnt how the activity goes: the human points, I sniff out something great. But in round two, the rules changed and the dogs became stressed out. But when round three came along, the human who broke the rules was replaced by a different human, and the dogs were happy to trust this one because of their love of trying new things.
"Dogs are very sensitive to human behaviour but they have fewer preconceptions," Bradshaw told the BBC. "They live in the present, they don't reflect back on the past in an abstract way, or plan for the future." And they certainly don't approach a situation by "thinking deeply about what that entails", he said.
Something to think about when you consider inflicting the 'fake tennis ball' game on your dog. It might work a few times for hilarious effect, because your dog trusts you way more than the dogs in the experiment trusted the strangers they just met, but how long will it last?
It also explains why dogs are so unsure about magicians: