According to a new study published in the journal Current Biology, Professor Takefumi Kikusui has found that dogs cry happy tears of joy when their owners come home.
A recent study found that many dogs also shed happy “tears of joy,” much like people, when their favorite humans return from work. Dogs frequently hop around excitedly when this happens.
Six years ago, when the poodle belonging to Professor Takefumi Kikusui gave birth to puppies, the dog’s expression changed as it breastfed the young. Tears welled up in his animal companion’s eyes.
“That gave me the idea that oxytocin might increase tears,” Kikusui says in a media release.
Dogs cry, according to the study’s author, but they don’t run down their faces way human tears do. When Prof. Kikusui of Azabu University in Japan investigated his hypothesis, he found that dogs shed more tears than usual when they were reunited with their owners. They continued to cry at the same volume even when they encountered strangers.
The dogs’ eyes filled with tears when the researchers injected oxytocin, confirming the theory that the release of oxytocin leads canines to cry when they are reunited with their humans. According to previous studies, when dogs interact with their owners, they naturally generate the hormone. However, research into how dogs respond when they see their absent owners is very recent.
The Japanese researchers also asked respondents to judge pictures of dogs’ faces with and without added tears, and they discovered that respondents preferred the teary-eyed animals more. This suggests that the tears of dogs help people and their dogs develop closer bonds. Prof. Kikusui was particularly shocked by the results.
“We had never heard of the discovery that animals shed tears in joyful situations, such as reuniting with their owners, and we were all excited that this would be a world first!” Prof. Kikusui explains.
“Dogs have become a partner of humans, and we can form bonds,” Kikusui concludes. “In this process, it is possible that the dogs that show teary eyes during interaction with the owner would be cared for by the owner more.”
Although the study, which was published in the journal Current Biology (pdf below), demonstrated that dogs cry in happy situations, it has not yet been tested on negative emotions.
The research team has not yet established whether dogs cry when they reunite with their canine pals, but they aim to determine whether this somatic reaction also has a social purpose in the canine world.
Read the study given below: