Do you get teary-eyed emotional when reunited with your dog? Fido might feel the same way. New research from Japanese scientists suggests that a dog's eyes may well up with tears of happiness when reunited with their owner after a period of absence. The tears may help cement the bond between human and dog -- a relationship that goes back tens of thousands of years. Like humans, dogs have tear ducts that well up with tears to keep their eyes clean and healthy. But tears in dogs, which tend not to fall as they do when humans cry, hadn't been linked with emotion before. 📷: InsideCreativeHouse/Adobe Stock