Have you ever been so happy you could cry? Of course, you have, but did you know that when you come back home from a day’s work and your dog is excited to see you that they’re doing the same thing?
— ian bremmer (@ianbremmer) August 23, 2022
That’s what a recent paper by Professor Takefumi Kikusui from Japan studying man’s best friend revealed recently.
According to The Scientist, dogs will cry happy tears of joy. “Although the animals’ eyes don’t overflow, they well up when they’re reunited with their owners after spending even just hours apart, the researchers found. And they have hunch as to why: a sudden increase in oxytocin, the so-called love hormone, named for its predominant roles in social bonding.
‘I thought it was a fantastic paper . . . ingenious,” says Lori Kogan, a psychologist at Colorado State University who wasn’t involved with the work—though she adds that the study is “very preliminary.” Kogan, whose research focuses on human-animal interactions and who has previously studied oxytocin dynamics in dog owners, says the findings align with both her professional and personal experiences with the animals. “What all of us who are dog owners know is that dogs are really, really happy to see us when we’re reunited,’ she says.
Kikusui’s group and others had previously found that pet dogs exhibit an increase in oxytocin levels when they interact with their owners. Kikusui says he and his team hypothesized that reuniting with their owner after a prolonged period apart “would be [an] emotional event to dogs,” marked by tear production and an underlying surge in oxytocin.
To test the idea, the researchers separated pups from their owners for several hours before letting the pairs reunite. Five to seven minutes into their reunion, the scientists performed a Schirmer tear test on the dogs to measure how teary their eyes had become. They then compared the results with tear production that occurred when the dogs were similarly separated from and then reunited with someone they knew but who wasn’t their owner. The animals’ eyes did, indeed, well up with tears upon reconnecting with their owners—significantly more so than when they reunified with their human acquaintance.
As if you needed another reason to show your pup some love, a 2020 study performed by Canine Cottages showed that when the dogs were told “I love you” by their owners, their heart rates skyrocketed 46 percent, from 67 bpm to 98 bpm.
People reported, According to the study, the dogs’ heart rates decreased by 23% on average from 67 bpm to 52 bpm while they were being cuddled by their owners.
Canine Cottages also tracked the owners’ heart rates to compare how much they love their pets. The results showed that their heart rates increased by 10% on average when they saw their dog after being away from them for a period of time.”
Cats on the other hand….