The breed of a dog says little about the temperament of the four-legged friend.

According to a recent study, many behaviors are hereditary, such as whether a dog is more playful, docile or alert.

However, the differences between individual dogs are usually greater than those between individual breeds, reports a team led by lead author Kathleen Morrill from the University of Massachusetts Chan Medical School (Worcester/USA) in the journal Science.

The modern dog breeds are less than 160 years old - a blink of an eye in evolutionary history compared to the origin of dogs more than 10,000 years ago, the scientists write.

Humans have bred dogs for about 2,000 years, most of the time for the roles they would perform, such as herding dogs, hunting dogs, or guard dogs.

It was only later that dogs were bred according to a physical ideal and with the idea of ​​lines that were as pure as possible.

To this day, behaviors are ascribed to the resulting breeds, which can also be traced back to their former areas of application.

The researchers now tested whether this is true in a large-scale study.

They collected information from 18,385 dog owners about the nature and behavior of their purebred and mixed-breed companions.

They also analyzed the genetic data of a total of 2155 dogs and linked them to the dogs' reported behaviors.

Differences in behavior between modern dog breeds are only slight

The evaluation of the survey data showed, among other things, that differences in behavior between modern breeds are generally only slight.

Overall, the researchers identified 11 regions in the canine genome that are associated with behavioral differences.

Although the researchers found certain patterns, they did not find any behavior that is exclusively found in one breed.

For example, beagles and bloodhounds howl more often, while border collies are particularly obedient;

but there were always exceptions.

While Labradors are considered a breed that rarely howls, some owners have reported that their pets do so sometimes or often.

Greyhounds are said not to bury their toys, but this behavior has also been reported by some owners.

In addition, behavior changed with age: puppies of many breeds were about as playful as German shepherds, which are considered particularly obsessed with toys.

Analysis of the genetic data showed that individual breeds had very few genetic characteristics.

Breed has little value in predicting a dog's behavior, the researchers write.

While most behaviors are hereditary, they are influenced by multiple genes and the environment.

Breed alone explains only about 9 percent of the differences in individual dog behavior.

The values ​​were higher for some behaviors, such as the tendency to howl or the desire to fetch.

Huskies, beagles and bloodhounds particularly like to howl, while border collies are particularly docile.

"While genetics play a role in an individual dog's personality, a specific breed of dog is not a good predictor of these traits," said study author Elinor Karlsson of the Broad Institute of MIT and Harvard.

"The defining criteria of a golden retriever are their physical characteristics — the shape of their ears, the color and texture of their coat, their size — not whether they're friendly."

Dog socialization with humans 'incredibly heritable'

When choosing a suitable dog, looking at the breed as a whole is only of limited help, explains Marjie Alonso from The International Association of Animal Behavior Consultants (Cranberry Township, USA).

"Breed will not decide whether we will be happy with a dog or the dog with us.

Appearance simply says little about how the dog will behave.”

During their investigation, the researchers made other interesting discoveries.

So the sociability of dogs in dealing with humans is "incredibly heritable", even if it is not determined by the breed, said study author Kathleen Morrill.

The researchers found a section of the dogs' DNA that could explain four percent of the differences in sociability.

A comparable farewell in the human genome is therefore responsible for the formation of long-term memory.

According to Morrill, research on dogs could also help to understand how the human brain develops and learns - and also provide a better understanding of mental and behavioral problems in humans.

"We're just scratching the surface," Morrill said

The scientists did not find any indications that certain behaviors are a consequence of breeding the breeds.

Most of the behaviors considered traits of certain modern dog breeds most likely arose thousands of years earlier, senior author Elinor Karlsson said in a press release.