The human-dog bond is ancient: we have co-evolved together since before writing even existed. Our long cohabitation with dogs has granted both species a unique insight into the other's feelings: dogs, for instance, know when you are looking into their eyes, unlike wolves and other animals. And, dogs can understand human language to some extent: one "Guiness"-worthy dog knows over 1,000 nouns.
Yet for all our mutual insights, we can't truly see inside the mind of a dog — nor can we know for sure what they're thinking, or what they do when we're not looking. And while cameras that watch our pets can reveal what they are doing, it's harder to know what they're thinking in private. What can dog owners know for sure?
When they are not peacefully snoozing, dogs may also engage in what is known as "vigilant behavior" — performing their self-assigned duty of guarding your home.
First, we know that they do indeed miss their humans. MRI tests of dogs' brains confirm that dogs associate the sounds and smells of their preferred humans with positive rewards. Because dogs are intelligent and perceptive about their environment, they quickly figure out patterns that indicate a human is about to leave — e.g., picking up their keys, walking toward the door — and clearly communicate feelings of distress when that happens. When secretly recorded, dogs who are alone in their homes often spend time at the door where their preferred human left, quite likely hoping they will soon return.
Yet if your heart aches at the thought that your dog does nothing but emotionally suffer while you are gone, rest at ease. There is plenty of research on domestic canine behavior and we know that, in addition to missing you, dogs routinely take naps.
"Previous research has demonstrated that dogs mostly spend their time resting when the owner is gone," Dr. Erica N. Feuerbacher, an Associate Professor at Virginia Tech's Department of Animal & Poultry Science, told Salon by email. When they are not peacefully snoozing, dogs may also engage in what is known as "vigilant behavior" — performing their self-assigned duty of guarding your home "likely when they hear or see something outside, like a car or someone walking down the sidewalk."
When they are neither tired nor on alert, dogs may occupy themselves with play. This is why humans may return home to find their property damaged.
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"Of course some dogs engage in behaviors that are probably less desirable to their owners, like counter surfing or getting into the trash or vocalizing," Feuerbacher explained. "Some dogs do develop separation anxiety which is a severe behavioral issue; other dogs are simply bored or take advantage of the owner not being there to explore places (like the counter) where they are usually forbidden from. But if they find something good up there to eat, that behavior will continue to happen."
It is important to remember that dogs, like humans, have quirks specific to their individual personalities. As such, anticipating their solitary behavior can be unpredictable.
"What dogs do when we are not around also depends on the individual, age, location and even the quality of relationship we share with them," Dr. Monique Udell, an associate professor who specializes in human-animal bonding at Oregon State University, told Salon by email. Puppies, for instance, are more likely to get into mischief because they are biologically programmed to spend more of their time in activities like exploring and teething. Younger dogs can also experience more frequent bathroom problems, similar to older dogs.
"Puppies, whose bodies are still developing, as well as older dogs who may be experiencing health problems or cognitive decline, are often less likely to be able to avoid urinating or defecating when left alone for longer periods of alone time," Udell pointed out. "Dogs with separation anxiety experience greater than normal distress when left alone, and may panic or try to escape, which can result in injury or damage to property." Like Feuerbacher, however, Udell emphasized that dogs spend most of their solitary time sleeping, and that this is healthy as long as the rest of their environment is sufficiently stimulating.
"Owners who have high expectations of their dogs and are highly responsive to their dog's needs are more likely to raise secure dogs."
"One important thing concerned humans can do, is make sure that the time they do spend with their dogs is quality time," Udell explained. "Dogs with secure attachment bonds to their owner are also less likely to display separation anxiety when their owner is away. Owners who have high expectations of their dogs (engage in positive reinforcement training, have consistent rules) and are highly responsive to their dog's needs (provide attention, recognize and respond when their dog is scared or sick) are more likely to raise secure dogs."
While dogs need their rest and therefore benefit from some time away from their humans, that does not mean all dogs will naturally accept that isolation. Fortunately, as Feuerbacher tells Salon, there are ways to train dogs to be as okay with temporary separation from you as you are from them.
"First, owners should work on their dog tolerating being left alone," Feuerbacher explained. "Dogs are social animals so the owner leaving can be upsetting to the dog. You can do this by practicing lots of short departures, like running out to check the mail and coming back in, gardening for a few minutes and coming back in, taking a quick trip to the grocery store. This is especially useful when you bring a new dog home."
It can also be helpful to leave dogs with toys and other enrichment items — bones, stuffed animals, chew devices, and so on. Finally, one should make sure to either paper train dogs or ask someone to take your dog out for a walk periodically if their humans will be gone for a while. It is cruel to expect the dog to hold in their excrement for too long. After all, while "The Secret Life of Pets" is not scientifically accurate, the essential point of the story — that dogs lead rich lives separate from their humans, and should be respected as such — is certainly true.
"While [the movie] might be fictional, I hope it does help folks recognize that their animals lead very rich lives, with their own interests — like smelling certain smells, or getting to visit a dog friend," Feuerbacher told Salon. "This also comes into play when we are interacting with our dogs — we might want them to sit or do some other behavior we want, but it's worth remembering they have their own interests (such as smelling a certain patch of grass!) that doesn't align with what I want them to do."