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Choosing a dog is more than a matter of aesthetics. Owners might enjoy their shiba inu’s thick coat and narrow muzzle, but appreciate its stoic nature and loyalty more. A chihuahua’s owner might enjoy its pint-size pick-up-ability, but value its playfulness above everything else. After all, every single breed page on the American Kennel Club’s website lists a breed’s personality and social traits alongside its physical characteristics.

A key factor for many dog owners is how easy their pooch is to train. A wayward bichon frise might be a slight nuisance in social settings, but a misbehaving rottweiler’s strength and size can pose serious risks. 

The AKC also offers a five-point scale of trainability for each breed. They list the border collie, German shepherd, and even the diminutive papillon as among the most trainable breeds. 

But recent genetic research into man’s best friend has shown that, at best, these scales simplify dogs’ complex inner worlds, and, at worst, are misleading about how dogs’ breeds affect their behavior.

Creating a dog genetic database

Elinor Karlsson first became interested in canine genetics while still a research trainee. She worked on the sequencing of the first complete dog genome—that of a boxer called Tasha. Karlsson is currently a genomicist at the University of Massachusetts Chan Medical School and Broad Institute of MIT and Harvard. In recent years, she has continued her doggy genetics work through a project called Darwin’s Ark.

Darwin’s Ark lets owners register their dogs in a database that records dogs’ behavioral traits alongside their breed type. “Right now, we have about 48,500 dogs registered,” Karlsson tells Popular Science. Several thousand of these dogs have also had their genomes sequenced, creating one of the world’s largest dog genetics databases. 

This trove of information helped Karlsson’s team see how breed and behavior are associated. They delved into this relationship in a 2022 study. One of the measured traits was “biddability”—essentially, how easy it is to get a dog to do something. This includes behaviors observed during training but, more generally, reflects a dog’s responsiveness to humans. 

Karlsson soon realized that there was a flaw in the purebred data from Darwin’s Ark. Owners might be more likely to recognize playfulness in a cocker spaniel as opposed to a dogo Argentino, because that’s the very trait that made them choose that breed in the first place. There’s a confirmation bias at play.

Luckily, nearly half of the dogs in the study were mutts, with complex ancestry and less breed bias. The mutts’ biddability sometimes contradicted breed stereotypes. 

For example, owners of Labrador retrievers tended to describe their dogs as more friendly toward humans, which aligns with the breed’s stereotype. However, having more or less Labrador ancestry did not affect how friendly mutts were with humans. Based on breed information alone, just nine percent of dogs’ behavioral patterns could be predicted. In other words, not a lot.

Identifying the most trainable dog breeds

What do these findings mean for dog training efforts? Biddability was one of the few behavioral traits with a stronger association in certain breeds. Owners were more likely to score Belgian malinois, vizslas, and border collies highly for biddability, and mutts with more ancestry from these breeds were also slightly more likely to be biddable. 

But that information isn’t really useful for determining whether an individual dog will be easy to train. Border collies might be fractionally more biddable on average, but there will still be collies that are more independent. On the other end of the scale, there will be chow chows that don’t mind following instructions.

Karlsson points out that this finding shouldn’t really be surprising when we think about the history of dogs. Purebred dogs are a modern invention, dreamed up by Victorians obsessed with genetic order. 

Breed standards over the intervening 150 years have been carefully selected for physical traits—for example, a Beagle has to stand roughly 14 inches tall at the shoulder—but behavioral traits have not been genetically selected in the same way.

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Nevertheless, selective breeding has created a population of dogs that are easy to train. Karlsson says Labrador retrievers selected to be guide dogs are genetically distinct from the wider Labrador population. 

This makes sense, as the average Lab would struggle to resist the temptation to eat its owner’s dinner rather than help them navigate. 

But this selective breeding comes at a cost. Analysis of guide dog populations shows that when complex behavioral traits are aggressively selected for, the risk of genetic disease in the dog population spikes, says Karlsson.

Ultimately, some dogs are easier to train than others. It’s just that looking at solely at breed information to find a biddable pooch is unlikely to get you very far. 

The next time you’re choosing a new best friend from the shelter, paying attention to the pooch in front of you rather than breed standards in a textbook will help you make the best decision. 

In Ask Us Anything, Popular Science answers your most outlandish, mind-burning questions, from the everyday things you’ve always wondered to the bizarre things you never thought to ask. Have something you’ve always wanted to know? Ask us.

 

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