Dogs Can Cry Tears of Joy When Reunited with Owners

Experts think that seeing us causes our dogs to produce more oxytocin.

Give your dog some extra rubs when you get home from work today, not just because it’s National dog Day but, because a new study in Japan found that dogs’ eyes well up with tears of joy when reunited with their owners. Researchers used a test to measure how watery 18 different dogs’ eyes were before and after they saw their owners 7 hours later. As soon as they saw them, their tear production increased by 10%. And it only happened with their owners. It didn’t happen with other people the dogs knew. The experts think that seeing us causes our dogs to produce more of the “love hormone” oxytocin, and that’s what makes them cry.