The Scientific Reason Why Dogs are Man’s Best Friend

The dog is one of the most popular household pets. They were the first species to be domesticated (~15,000 years ago) and are known to have a unique attunement to human behavior. But what exactly makes them man's best friend? The answer may have something to do with hormones.

Oxytocin, often called the love hormone, is both a peptide hormone and neuropeptide. Neuropeptides are the name for peptides that can also act as neurotransmitters, which are vital for communication between neurons. Oxytocin is primarily produced in the hypothalamus, which is one of the most important organs in the human body-it regulates hormones and helps us maintain homeostasis. From the hypothalamus, oxytocin is transported through nerve axons to the pituitary gland, where it is secreted into the bloodstream to bind to oxytocin receptors.

Oxytocin is involved with increasing uterine contractions during labor, breastfeeding, and it causes mothers to display "mothering behavior". It is also important for romantic relationships, because it improves your mood and feelings of attachment. Increased oxytocin levels have also been shown in several studies on humans when they interact with their dogs.

In a 2015 study, researchers found that dogs who gazed at their guardians for longer periods of time had higher oxytocin levels than dogs who did not maintain eye contact for as long. In the same study, it was found that female dogs who were administered oxytocin intranasally gazed at their guardians for longer periods of time, and humans who interacted with these female dogs also experienced increased oxytocin levels. Interestingly, this experiment did not affect male dogs the same way, and the reason for this is unknown.

Oxytocin can also affect a dog's responses to our social cues. In a 2015 study, researchers conducted an experiment in which dogs were divided into two groups, and one group was given an injection of oxytocin. The dogs with injected oxytocin were more responsive to a human's social cues than the dogs with no oxytocin. When the human looked at and pointed to the location of hidden food, the oxytocin group was overall more successful at following these cues and finding the food.

Oxytocin may also cause dogs to perceive negative social cues as more positive. Researchers of the University of Helsinki's Canine Mind project conducted an experiment in which they showed dogs several images of 43 angry and happy faces. They were tested twice: once under the influence of oxytocin, and once without oxytocin. By using eye-tracking devices, the researchers were able to measure each dog's emotion and attentiveness. It was found that dogs under the influence of oxytocin were more interested in the happy faces than the angry faces, but without oxytocin, dogs reacted more powerfully to the angry faces.

Dogs aren't called man's best friend for nothing; there is a scientific reason why they are so loyal and loving to their owners. Oxytocin has been shown to play a significant role in the development of a life-time bond between you and your furry friend. Interactions between dogs and humans have been shown to increase oxytocin levels in both parties, so for those of you who don't have a dog yet: what are you waiting for?

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