How can you tell what your pet is feeling? Many pet owners say they know when their dog is happy and their cat is sad.
Marilyn Brisken is sure her beloved Dewy has emotions, but are emotions really possible for a pooch?
"He can be happy, he can be sad, he can be angry as hell," she told WABC-TV in New York. "He does a terrific angry."
While it's natural for human companions to anthropomorphize their pets, researchers say the idea of pets having emotions may not be as strange as it sounds.
"A few years ago if you asked a scientist to discuss animal emotions they might laugh at you," said Robert Defranco, director of the Animal Behavior Center in Queens, N.Y., and author of several research papers on animal emotions.
Defranco says animals definitely have primary emotions like fear. They can also feel anger. And now there is growing evidence that they have secondary emotions like love, jealousy and greed. The proof may rest in the part of the brain called the amygdala. It's believed that fear and possibly other emotions are linked to neurons in the amygdala.
"It's a larger area in dogs than it is in humans. So we could say that the dogs will experience more emotions. They live very much more in the moment than humans do," Defranco said.
The Dog Whisperer
You don't have to convince Mike Malloy, who works as a dog whisperer at the North Shore Animal League in Long Island, N.Y. He trains dogs by listening to them and reading their emotions.
He agrees dogs have human-like emotions. "Oh yeah, definitely," he said. "I think they miss the way people miss love ones, they hurt the way people hurt, they grieve."
Pet photographer Rachel Hale tries to captures such emotions in her portraits, including a recent sitting with a dog named Henry. "Every single image I take of Henry, he chose a different emotion," she said.
People may believe their pets are feeling emotions like sadness, love and joy, but are we really just projecting those emotions onto our pets?
Brisken has no doubt that her dog feels at least one emotion: "Oh, I know he loves me," she said.
Lauren Glassberg of the ABCNEWS station WABC-TV in New York contributed to this report.