The breed of the dogs does not determine their personality

You can't have a Great Dane the size of a Chihuahua, or vice versa.

But you can have a Great Dane that behaves exactly like a Chihuahua.

And vice versa.

With this comparison, researcher Elinor Karlsson summarizes her work in recent years, in which she has been looking for the genetic basis of dog behavior.

Now she, along with her team, publishes a monumental paper in the journal

with a conclusion that will disappoint many: a dog's breed doesn't say much about its personality.

The team studied the genetics of more than 2,000 dogs to try to find behavioral traits linked to certain genes, which were crossed with the different breeds in the sample, including those of their ancestors, detected genetically.

The results of these tests, which included data from 78 breeds, identified genetic regions that were strongly associated with behavior, but none were breed-specific.

The variability is such that the researchers were unable to find personality traits that were unique to any one race.

"Behavioral factors show great variability within breeds, suggesting that although breed may affect the likelihood of a particular behavior occurring, breed alone is not, contrary to popular belief, informative enough to to predict the disposition of an individual”, they conclude in their study.

We are talking about characters such as sociability with humans and with other dogs, aggressiveness, tendency to use toys or docility.

In addition, they analyzed the ancestors of satos, without breed, to pull the genetic thread of traits beyond the pedigree.

A woman plays with her Komondor sheepdog in Bodony, Hungary, in 2017. LASZLO BALOGH (REUTERS)

Although it is believed that such a breed is good with children and another is more skittish, at the moment of truth, when an animal is adopted it is impossible to know if it will have that character.

Breed only explains 9% of behavioral variation in individual dogs, and for certain traits, age is a better predictor of behavior.

And, furthermore, as Karlsson points out, these stereotypes are not universal: the characteristics attributed to a race in the US are different in France.

"Behavior in dogs, just like in humans, is complex, which means that it is controlled by changes in many, many different genes," insists Karlsson, who recalls that there is also a large environmental component.

"The maternal environment, early socialization, possible traumatic events, all that sort of thing," he lists.

Therefore, from a genetic point of view, selecting for complex behavioral traits would take many centuries.

“The idea that they would have been created in the last 160 years when these breeds emerged made no sense at all,” she says.

They are not peas

Dogs were domesticated about 15,000 years ago from a common ancestor shared with today's wolves, probably self-domesticated in their interest in sharing their lives with humans.

It was from that moment, for millennia, that the general traits that define all dogs began to be genetically selected: docility, sociability with people, the ability to interact by picking up an object or looking where the owner indicates.

But only in the mid-nineteenth century did breeds begin to be isolated around fixed characteristics that defined them: Dalmatians with spots, bulky mastiffs, etc.

But those of all dogs are practically the same, it only varies in a handful that influences accessory aspects such as the shape of the ears or the length of the hair.

And that is why they constitute the same species: the recipe is the same, although some have more salt or less pepper, depending on their appearance.

Aesthetics, and not behavior, have been the focus of selection, they note in the study: "We found no evidence that behavioral trends in breeds reflect intentional selection by breeders, but we cannot exclude the possibility ”.

And for this reason, the physical traits correspond exactly to the breed, but not the behavioral traits, which are more complex, as explained by Carles Vilà, a specialist in evolutionary genetics at the CSIC.

“They are not determined by a single gene, but by many, and that makes it more difficult to predict what will come out of a cross.

They are not like Mendel's peas, smooth, wrinkled, green or yellow, but there are many levels of variation and many genes involved.

A great deal of variation can be found in offspring,” says Vilà, who has also studied canine lineages.

Hence, it is not possible to have a Chihuahua the size of a Great Dane, but they behave the same.

Border colliers are widely used in grazing and mastiffs like this one to defend themselves against possible wolf attacks in Zamora.© Luis Sevillano

To analyze behavior, the study relied on 200,000 responses from more than 18,000 dog owners from a giant citizen science repository (Darwin's Ark).

Thus, they discovered that no behavior is exclusive, or foreign, to any race.

Even in the lowest propensity to howl, Labrador Retrievers, 8% of owners report that their Labrador howls, for example.

Of course, there are breeds with specimens with a greater tendency than others to show some behaviors: it is very likely that a bloodhound howls, and it is more difficult to find an obedient beagle, but they all move in a variable spectrum.

aggressive and professional

In these nuances they stand out above all with the most recently selected breeds with the aim of using them in specific tasks.

"If you have a population of guide dogs where you're selecting individuals that are fantastic guide dogs, they will have population-enhanced behavioral differences in that group," Karlsson explains.

For this reason, dogs bred for herding show greater obedience than, for example, a chihuahua.

Does it make sense, therefore, to classify certain breeds as more dangerous?

In the study they analyze the prevalence of a trait, the agonistic threshold, which measures the ease with which a dog feels provoked by stimuli that cause fear, discomfort or annoyance, and the breed provides almost no information for that aspect.

Asking Karlsson at a press conference, he acknowledges that they are not specialists in that, nor have they studied it specifically, but he clarifies: "When we studied the agonistic threshold, which included many questions about whether people's dogs reacted aggressively to situations , we did not see an effect of racial ancestry on that particular factor.

From that point of view, [that cataloging] doesn't seem to make much sense to us."

To Vilà, who has not participated in the study, the conclusions of this work seemed as surprising as solid.

"Many times we pigeonhole animals, that they have to be like this or that, but the family environment is not taken into account, how the animal has been raised, age, and that there are other factors that are very important, that are saying that you have to take into account other things apart from race”, says the researcher from the Doñana Biological Station.

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