As the University of Nebraska–Lincoln’s resident dog expert and researcher of canines, Jeffrey Stevens is ever on the lookout for labs that might join upcoming studies.
Enthusiasm is a must, naturally. Some training is vital. As is the ability to play well with others.
Chocolate, yellow or black? Sign ’em up. How about cognitive, behavioral or otherwise research-focused? They are more than welcome, too.
When you co-direct the ManyDogs Project, an international consortium of 25-plus labs devoted to elevating the study of human’s best friend, you never really stop recruiting — canines, of course, but also groups of people with the requisite curiosity and know-how to study them.
Because as it turns out, the ManyDogs Project, and canine science at large, still need plenty of both. That might come as a surprise, considering that the world now boasts an estimated billion or so dogs, and even more dog-lovers. But while humans may have begun domesticating dogs roughly 25,000 years ago, they didn’t start studying canines in earnest until about 25 years ago.
Stevens is still relatively new to the scene himself, having founded the Canine Cognition and Human Interaction Lab in 2018, following a sabbatical trip to the Clever Dog Lab in Vienna. When he did, he saw that the field had generally been losing the numbers game.
“Once I started getting into the dog world, I noticed that there were all these dog labs popping up all over the place,” said Stevens, a Susan J. Rosowski Professor of psychology at Nebraska. “But often, the sample sizes were really small — like, 15 or 20 dogs.
“That’s just not a large enough sample size to draw strong conclusions about anything, especially when you have such a huge potential population to draw from.”
It didn’t take long before he realized one possible reason: The same loyalty that so endears dogs to their owners also complicates their ability to participate in research. Having begun leading canine-focused studies of his own, Stevens was stunned to learn that roughly 50% of the dogs enrolled in a study wouldn’t wind up completing it — a dropout rate that other researchers confirmed was just a reality of the research.
“And I think the key piece is separation anxiety,” said Stevens, who has three dogs. “The dogs live with their owners 24/7 — they’re with them all the time. Many of the dogs don’t do well when they’re not with their owners. But in some of our studies, you either don’t want the owner in the room to avoid bias, or you keep them out of the way so that they don’t interfere. And the dogs don’t like that.”
So when the ManyDogs Project, then already 10 or so labs strong, extended an invite to the Canine Cognition and Human Interaction Lab, Stevens immediately accepted. In it, he saw a team of kindred academic spirits: researchers who valued reproducible, transparent methods, rigorous experiments, and the larger sample sizes needed to answer even fundamental questions.
One such question surrounds the differences among breeds, which is often the first topic that dog owners will raise with Stevens — usually with an eye toward learning more about their own pups. Anyone who has spent time around, say, both a chihuahua and a bulldog knows that breeding has introduced distinctions that extend beyond the physiological to the temperamental and behavioral. Depending on who is counting, though, the number of breeds now sits somewhere between 200 and 400, the latter of which includes mixed breeds.
A research lab alone, or even collaborating with a few partners, could not possibly hope to disentangle all that cognitive and behavioral nuance with just a few dozen dogs, Stevens said. The strength of its numbers, and those it recruits, should give ManyDogs a leg up in combing apart the influences of breed.
“To me, that is huge, because I think there are a lot of potential misconceptions about breeds,” Stevens said. “People sometimes think of them more like species, in the sense of: This breed does this, and that breed does that. But there’s so much variation within breeds. In many cases, there’s more behavioral variation within a breed than there is between breeds.”
With research labs already spread across North America, Europe and South America, the ManyDogs Project is poised to answer another lingering question: Do the beagles, greyhounds and Shiba Inus living among the people of one continent behave the same as their counterparts living on another? For a species whose domestication stemmed, in part, from reading the emotional cues of humans and forming social bonds with them, the idea that cultural norms might sway canine behavior hardly seems a stretch, Stevens said. Testing that intuition is high on the to-do list.
“We don’t have good evidence of this yet, except for mixed results that are occurring across different locations, and not really understanding why those exist,” he said. “But one really clear possibility is that there are just differences in how people in different cultures interact with their dogs. And I think that can trickle down into what we find out about them in these studies.”
Then there’s the nontrivial matter of replication, whereby one research group runs a study previously conducted by another for the sake of determining whether any findings, or lack thereof, hold up under repeat testing. Because they rarely earn a research team plaudits, promotions or major grants, replication studies are far less common than original research.
Still, replication is a central tenet of science — one espoused by both the ManyDogs Project and Stevens, whose initial canine experiment tried, and failed, to replicate the findings of an earlier one.
“So in my very first dog study, I’m already grappling with this inability to replicate published findings,” he said. “I’m very sensitive to this.”
In its first study, the ManyDogs Project replicated experiments that had yielded mixed results when examining whether dogs that followed the pointing cues of their owners recognized that pointing as a form of communication — or obeyed simply because they associated it with rewards. To test the distinction, 20 of the ManyDogs research groups assembled a total sample of 455 dogs. In one condition, an owner pointed to a treat-containing cup, as opposed to an empty one, after making eye contact and saying their dog’s name. In the other, the owner instead avoided eye contact and cleared their throat to draw the dog’s attention.
Overall, dogs fared no better at picking out the treat-filled cup when directed by the more communicative, name-affiliated point than they did when guided by the less personalized one. In fact, the dogs selected the correct cup only slightly more often than would be expected by chance (though Stevens suspects a more overt pointing gesture could have proven more effective).
The study’s massive sample size, combined with the consistency of the findings across research groups, allowed the ManyDogs team to feel confident that the lack of difference was real rather than the byproduct of study limitations.
“It can actually be tricky to show no effect of something,” said Stevens, a core faculty member of Nebraska’s Center for Brain, Biology and Behavior. “No effect can just mean that there’s a lot of variability and a pretty low sample size.
“We have the sample size to deal with the variation (across dogs) that we might be seeing. So we can show pretty definitively that, in our dataset, there actually was no effect — which is something you can’t necessarily do with individual labs.”
For all the benefits of such a large, wide-ranging team, Stevens conceded that co-directing a consortium that spans continents, time zones, languages and cultures also presents plenty of challenges. The communication demands alone — reaching out, following up, replying to multiple people from multiple groups — are daunting enough. Coming to a consensus on the next study can entail some negotiation. Ensuring that every group follows agreed-upon protocols can require time and grace. Lowering the barrier to entry is a constant consideration, too.
“You have to design an experiment that’s easy to do, such that any lab can just sign up and do it,” Stevens said. “You can’t have specialized equipment. You can’t need the dogs to come in 12 times. It’s got to be something that basically any dog lab that has a room can do with modest materials. We try to make things as simple as possible, just so that we can get as much buy-in as possible.”
But the opportunity to draw on the considerable brainpower of so many minds with so many different perspectives, he said, is more than worth the effort. And it helps that his ManyDogs colleagues are “the most fun people I’ve ever worked with.”
“I’ve done collaborative projects before,” he said. “Some of them fall apart; some of them work, and they’re OK. But this is one where it was like, ‘I really like working with these people!’ in a way that I hadn’t before.”
The consortium has more in store. It’s already planning its next study, which will assess whether dogs imitate only the actions needed to complete a task or, like human infants do, copy-and-paste even the superfluous steps that do not help them achieve a goal.
Stevens and his colleagues also want to expand not just the ManyDogs Project’s membership, but its geographic and cultural reach, with researchers in Brazil, Japan, New Zealand and elsewhere now showing interest. That outreach could help the consortium study the consequences of a fact that amazed Stevens: An estimated 75% of dogs worldwide live not as pets in homes but as free-ranging animals. Recruiting more colleagues from areas of the world where those dogs are the norm could allow the consortium to better compare them with housed canines.
And with ManyDogs only one among multiple iterations of the ManyX template — it was preceded by ManyPrimates, ManyBabies and many others — the consortium has joined the ManyManys Project, a meta collaboration that examines cognition and behavior across animal groups. (“Can you imagine,” Stevens asked with some wonder, “developing a project that a guppy and an elephant can both do?”)
In the meantime, the ManyDogs Project will continue relying on the two-legged caretakers who, like Stevens and his colleagues, adore their dogs every bit as much as their furry friends adore them.
“These owners really enjoy bringing their dogs in. So it’s really great to interact with them,” he said, “and to see how engaged they are in what we’re doing and what we’re finding, too.”
Dog owners interested in joining future studies through the Canine Cognition and Human Interaction Lab can register and enroll their dogs at dogcog.unl.edu.
