DEAR DIDI: Why don’t dogs shed tears when they cry? – Manteca Dog Lover
DEAR DOG LOVER: This question may seem simplistic at first, but it is actually one of the most intriguing and complicated questions I have ever received. Humans are fascinated by anything that is different in our world, especially if it doesn’t fit a normal pattern. We instantly are curious and driven to find out why that thing or animal is different. Ultimately, finding the answer to those questions usually leads back to us, in our never ending quest to understand the human species better.
Canine eyes do produce tears. Like any land animal, their eyes produce lubrication to clear debris, irritants or simply rehydrate the eyeball and surrounding tissues. Excessively watery eyes or tears that are thick with mucus should be looked at by a veterinarian. Your dog may have an ear infection, a foreign object in the eye, allergies or simply over dry eyes. These would be physiological causes for tears to roll from your dog’s eyes.
Honestly, the more interesting question is, “Why do humans cry tears for emotional reasons?”
We are the only species on the planet that does! So that makes US the different that isn’t fitting a normal pattern of behavior. Yet, we wonder why our beloved canine companions don’t shed tears when they cry. Lots of studies have been conducted over the decades and many opinions have been offered throughout time with regard to our emotional flow from the eyes. Unfortunately, it is still one of science’s unsolved mysteries. There are some beliefs that people still cling to steadfastly, such as, crying releases stress hormones but nothing in science truly supports that idea.
Puppies are born with their eyes closed so tears aren’t as necessary. Puppies are frequently out of their mother’s sight also. Instead, whimpers seem to get their mom’s attention quite rapidly and signal when a pup is in distress. Human babies also vocalize to get attention. The intensity and pitch of those vocalizations typically relay the severity and urgency of the distress call.
One must be looking at the individual that is crying to realize they are hurting whereas whimpers, sobs, and other sounds can be heard even from another room. We are the unique and different species in this case because we shed physical tears for purely emotional reasons sometimes. Although science is quite fascinated with those humans that never cry. Why is it that some of us cry easily out of frustration while others of us never cry even if their entire world is crumbling?
Then I found a Danish study showing that emotional tears have a slightly higher protein content than lubricating tears. The scientists hypothesized that lubricating tears roll faster and therefore clear dust from the eye more efficiently. Emotional tears with their higher protein are stickier and therefore roll more slowly down the face. Perhaps this would give other humans time to notice the distress signal and respond to it? Either way, most of the scientists can agree that crying emotional tears is a uniquely human event and is very important in making meaningful connections with others of our species.
Dierdra McElroy is a graduate of Texas A&M University and is an Animal Behaviorist specializing in canines. If you have questions or concerns about the pets in your house, you can get them answered through a future column of Didi’s Dogs. For a free consultation with Dierdra or to ask your dog behavior question, email www.CaliforniaCanineUnleashed.com.