The dogs had a noticeable effect on morale. The lab felt more relaxed. The students were less distressed by whatever problems were cropping up in their research. The simple brush of a dog walking by, or the press of a cold, wet nose on your hand, was enough to drop anyone’s stress level. People laughed more.
The beneficial effects of dogs in the workplace have been well documented. Sandra Barker, a professor at Virginia Commonwealth University and director of the Center for Human-Animal Interaction, has been studying the effects of pets at work for more than a decade. In 2012, her team measured stress levels of workers who were allowed to bring their dogs to work. Normally, stress is lowest in the morning and rises steadily throughout the day. But the presence of dogs kept self-reported stress at their morning levels all day long. The researchers also found that the presence of dogs increased communication between workers.
Whether these effects on stress are simply a matter of perception has been difficult to determine. The most concrete proof would be reductions in the body’s stress hormone, cortisol. Cortisol is produced by the adrenal glands, which sit on top of the kidneys. When a person is stressed for any reason, the brain sends a signal to the pituitary gland, which releases a hormone that flows through the blood to the adrenal gland, causing the release of cortisol. The effects are nearly instant. Cortisol causes blood pressure to rise and the heart to beat faster. These are beneficial effects if you need to jump into action, but if the adrenal gland continues to release cortisol because of chronic stress, its effects will begin to damage the body. Chronically high levels of cortisol cause stomach ulcers, hypertension, and diabetes.
Some studies have found that dogs decrease cortisol levels, while others have not. There is relatively little research in this area, so much of the variability in results probably comes from the variety of conditions in which dog-human interactions have been studied. Not everyone likes dogs, and as Lyra proved at the lab party, dogs can send cortisol levels skyrocketing in people who are afraid of them.
Even though there is not a lot of biological evidence yet to prove that dogs have health benefits for humans, some companies have recognized that their employees are happier and more productive when they are with their dogs. Google, for example, states, “[Our] affection for our canine friends is an integral facet of our corporate culture. We like cats, but we’re a dog company, so as a general rule we feel cats visiting our offices would be fairly stressed out.” Amazon has a similar policy, simply requiring that employees register the dog and be responsible for good canine citizenship (barking and peeing are no-no’s). Other large companies with dog-friendly policies include Ben & Jerry’s Ice Cream, Clif Bar, the Humane Society headquarters, Build-A-Bear Workshop headquarters, and the software maker Autodesk. And, of course, many small businesses around the country.
If having dogs at work makes the humans less stressed, do the dogs feel happier too? The question is embedded in the much deeper riddle of animal emotions and gets to the heart of why we were doing the Dog Project.
For the most part, scientists have ignored the question of whether animals have emotions. This is peculiar because most pet owners are pretty sure that they do. Science, though, deals with things that you can measure, and, by definition, emotions are internal. Science has been able to measure only behaviors that are a result of an emotion. With humans, this is not a problem. You can always ask a person how he is feeling and deduce which emotion is associated with a behavior. The linking of subjective states and objective behaviors is an important step because different emotions may result in similar behaviors and expressions. For example, if you see someone crying, you might assume he or she is sad. But those could be tears of joy. The only way to know is to ask.
This inability to exactly determine emotions from behavior is why scientists have generally avoided the question of animal emotions. For example, a dog can’t tell you why he chews your slipper. But scientists have not always been so reluctant to venture into this. Charles Darwin devoted an entire book to the topic. In The Expression of the Emotions in Man and Animals, Darwin described how emotions like joy and fear have common manifestations in both animals and humans. Although Expression of the Emotions was his third book, after his famous books on evolution, it is the one that resonates most strongly today. The timelessness comes from his heavy reliance on dogs to illustrate his points. Richly illustrated with photographs and engravings, the modern reader can immediately identify with Darwin’s dogs.
Because humans and animals evolved from a common ancestor, Darwin deduced that we might also share basic emotional functions. If that were the case, animal emotions would help reveal the origins of human emotions. Unlike other scientists of his era, content to simply describe natural phenomena, Darwin wanted to understand why emotions manifested the way they did. Why, for example, does happiness trigger an upturned mouth as opposed to a downturned one?
Darwin formulated three principles of emotions that applied to man and animals. First, he said that emotions come from the brain. This was a pretty remarkable and correct intuition, considering that almost nothing was known about the brain in 1872. Second, emotional expressions build on natural movements. For instance, smiles are upturned because laughter triggers the closing of the eyes, and the contraction of the muscles around the eyes also raises the corners of the mouth. Third, Darwin believed that emotions manifest as the opposite actions of opposing habits. Darwin chose a dog to illustrate this principle, which he called antithesis.
When a dog approaches a stranger that appears hostile, the dog “walks upright and very stiffly; his head is slightly raised…; the tail is held erect and quite rigid; the hairs bristle… the pricked ears are directed forwards, and the eyes have a fixed stare.” These actions are defensive and may represent a prelude to an attack. The principle of antithesis states that the opposite emotion—joy—manifests with opposite motions. “Instead of walking upright, the body sinks downwards or even crouches…; his tail, instead of being held stiff and upright, is lowered and wagged from side to side.” The descriptions are as apt today as they were 150 years ago.
Darwin’s work on emotions was forgotten for more than a century. Although serious research in this area is beginning to attract scientists again, the vast majority still stays away from the knotty question of animal emotions. A major factor in scientists’ reluctance is that the study of animal emotions opens up an uncomfortable ethical question. If animals have emotions like humans, is it right to kill and eat them?
There have been a few exceptions. Within neuroscience, two people stand out. Kent Berridge, a psychobiologist at the University of Michigan, has extensively studied the link between reward systems in the brain and the expression of emotion in rats. And Jaak Panksepp, a neuroscientist at Washington State University and Bowling Green State University in Ohio, has been the strongest advocate for mapping animal emotions onto corresponding brain systems that are common to all mammals.