From wagging tails to expressive eyebrows, dogs already have plenty of ways to express their emotions to people.
But scientists have found another surprising way to tell you something important: by blinking.
A study found that dogs use blinking as a “subtle affiliative signal” when looking at people they are close to.
That means your pet’s fluttering eyelashes could be an attempt to convey friendliness or build a closer social bond with you.
In the study, scientists from the University of Parma Italyfound that dogs blinked faster when they saw a human blinking, compared to when they saw images of someone staring.
However, the effect only occurred if the person in the video was the owner.
Lead author Dr Chiara Canori told the Daily Mail: ‘I believe this suggests that dog-human communication may be more subtle and responsive to social relationships than we actually recognize.
“There may be a much richer layer of communication in these small, overlooked behavioral changes, and learning to recognize and acknowledge them could help us better understand our dogs.”
If your dog blinks at you, researchers say it could be a “subtle affiliative signal,” meaning it’s meant to convey friendliness or strengthen your social bond
Researchers found that dogs started blinking faster when they saw a human blinking, but only if it was their owner. The effect was also greater if the owner was a woman
“At its most basic level, blinking is a physiological behavior that protects the eye and maintains the ocular surface,” says Dr. Canori. ‘Interesting is the possibility that this very old, automatic behavior has also acquired some social relevance.’
In their study, the researchers showed videos of 35 dogs in which people blinked their eyes open or stared straight ahead.
When the dogs saw videos of people staring, their blink rate remained unchanged.
However, when they saw images of owners blinking, their blinking frequency began to increase.
Unusually, this effect was strongest when the owner was female.
The authors suggest that this effect could reflect the greater attention and social involvement a dog has with its owner compared to a total stranger.
The authors caution that they cannot yet determine whether these blinks have specific meaning beyond social engagement.
Scientists showed dogs videos of people blinking or staring straight ahead and recorded how their own blink rate changed
Dr. Canori says, “Our research does not show that a dog deliberately ‘says something’ every time it blinks; rather, it suggests that this apparently simple and automatic behavior can be influenced by social context.”
That observation, however, does reveal a glimpse of the fascinating complexity of the relationship between dogs and humans.
Previous studies have shown that dogs are capable of this tell the difference between people’s happiness, anger, fear and sadness just by facial expressions.
Researchers found that seeing a smiling human lights up a unique part of a dog’s brain that doesn’t respond to negative facial expressions.
Likewise, research has even shown that dogs have the unique ability to do this smell human stress in our sweat and in our breath.
Blinking also appears to have some social relevance in other animals. For example, cats will return their owners’ slow blinks as a sign of affection, and are more likely to approach people who have blinked at them first.
‘The fact that dogs modulated their blinks depending on whether the human was their owner suggests that their responses are not simply triggered by seeing a human face or movement, but may be influenced by the social relevance of that specific person,’ explains Dr Canori.
‘The connection between dogs and people is therefore not only built through obvious signals such as vocalizations or gestures, but also through these much more subtle, dynamic behavioral signals.’
