Do dogs cry tears when they are sad, happy, or in pain, similar to how humans express emotions through tears? If so, what is the physiological mechanism behind emotional tear production in dogs, and does the chemical composition of those tears differ from tears produced due to physical irritants or allergies? Are there specific breeds or age groups of dogs that are more prone to emotional tearing than others, and what behavioral cues accompany emotional tearing in dogs that would help an owner differentiate it from other causes of tear production? Also, has there been any scientific research conducted on the neurological pathways involved in emotional tear production in dogs and how they relate to their limbic system and emotional processing centers of the brain?

Answer

While dogs don’t cry tears of emotion in the same way humans do, they do produce tears for physical reasons. They have tear ducts that function to keep their eyes lubricated and clear of debris. So, if a dog has allergies, a blocked tear duct, an eye irritation, or another eye issue, they can certainly tear up.

However, the tears associated with human emotional responses are biochemically different. Human emotional tears contain stress hormones like prolactin, adrenocorticotropic hormone (ACTH), and leucine-enkephalin, a natural painkiller. These substances haven’t been found in dog tears.

Furthermore, the reasons behind human emotional crying are complex and linked to our social and cognitive abilities. We cry from sadness, grief, joy, frustration, empathy, and a wide range of abstract emotions. While dogs certainly experience emotions like joy, fear, anxiety, and even grief, there’s no scientific evidence that they link these feelings to tear production in the same way humans do.

Dogs do express their emotions in other ways, such as through body language (tail wags, ear position, posture), vocalizations (whining, barking, growling), and facial expressions (relaxed mouth, lip licking, showing teeth). Their expressions of distress, like whining or whimpering, can sometimes resemble human crying to our eyes and ears, leading to the common perception that they are crying emotionally. However, those are separate expressions, not necessarily connected to the tear ducts being activated by sadness.