Dogs are considered some of the most intelligent animals on the planet. Thanks to a relationship with humans that dates back tens of thousands of years, dogs can respond to emotions, recognize numerous words and be trained to follow commands.

Notably, these seemingly smart accomplishments all hinge on the partnership between our two species. Now, however, tests of canine problem-solving skills indicate that dogs rely on humans so much that we actually seem to be dumbing them down.

Most studies that investigate dog intelligence assume that certain interactions with humans are indicative of higher cognitive function. In one experiment, for example, dogs and human-socialized wolves were presented with a canine version of the Kobayashi Maru—an unopenable box that contained food.

When confronted with a difficult task, dogs often turn to us—their human masters—for guidance, indicating their puzzlement with a cock of the head and eyes that seem to implore for help. Indeed, the dogs in the study quickly gave up and simply stared at the nearest human. The wolves, on the other hand, sought out no such help and persisted at trying to solve the impossible puzzle on their own.

Researchers usually interpret such findings as a sign of dogs’ intelligence; the wolves kept trying to win the no-win scenario, while the dogs knew that humans could help out with tasks they themselves could not solve.

But depending on humans for help is not necessarily a cognitive asset, points out Monique Udell, an assistant professor of animal and rangeland sciences at Oregon State University.

If dogs only turn to humans when presented with an impossible task—not a solvable one—then their “look back” behavior would indeed be advantageous. On the other hand, if they simply throw their paws up at the slightest hint of cognitive challenge, then that could indicate “a conditioned inhibition of problem-solving behavior,” as Udell puts it. Like a child whose parents always give away the answers to homework, dogs may be overly reliant on us, she surmised.

To test this hypothesis, Udell presented ten pet dogs and ten human-socialized wolves with a solvable puzzle. Sausage was placed inside a sealed plastic tub with a lid that included a bit of rope. With some paw and mouth finagling, the lid could be opened.

She also included ten shelter dogs in the study, because past research shows that shelter dogs are initially less responsive to humans compared to established pets. These animals acted as a sort of intermediary between hyper-socialized dogs and wolves.

Udell presented the canines with the puzzle box both in the presence of humans—an owner, caretaker or familiar person—and without any person nearby. Each time, the animals had two minutes to figure out how to get at the sausage. Subjects that failed in both trials were given a third and final try in which they also received verbal encouragement from their human friend.

Udell’s findings, reported today in the journal Biology Letters, were telling. In the presence of humans, just one pet dog and none of the shelter dogs managed to open the box. Eight out of ten of the wolves, however, succeeded in enjoying the sausage treat inside.

Wolves also spent more time chipping away at the problem and more time staring at the box, as if working out how to open it. Both pet and shelter dogs, on the other hand, did the opposite—they gave up more quickly and stared at humans instead of the box, seemingly asking for help.

When humans were not around, the findings were similar—nearly all of the wolves figured out how to open the box, while just one shelter dog and no pet dogs succeeded. In the third and final trial, dogs that had failed in both of the prior tests performed a bit better when humans encouraged them.

With some human cheerleading, four of nine shelter animals and one of eight pet dogs opened the box, and all spent more time trying to open the box and looking at the box than they did when they were either alone or when their human friends remained silent.

Udell's results indicate that dogs do seem to be overly dependent on us compared to their wild relatives, although the cause of this—whether biological, environmental or both—still needs to be worked out.

Lucky for pet pooches, however, we humans will no doubt always be there to help them navigate all of life’s tricky plastic containers.