Every night, suburban parks fill with a mix of pooches of all shapes and sizes blowing off some steam while their doting owners look on.
- US scientists analyzed a survey of more than 18,000 dog owners and sequenced the genomes of more than 2,000 dogs
- They found that breed stereotypes are a poor predictor of individual dog behavior
- They say the results challenge current assumptions about dog breed stereotypes, which are used to explain why some breeds are more aggressive, obedient or clingy than others
Parks have been swollen with young dogs and first-time owners lately as pet ownership has boomed from the pandemic.
Some dogs are very social, others will bark at strangers, some will fetch, and others will let their humans do all the work.
While it may be tempting to attribute the behavior of these four-legged companions to their breed, a new study published in the journal Science suggests that breed is not a good predictor of an individual dog’s behavior.
“I have a feeling that sometimes people look at breed as a kind of catalog shopping,” said study co-author Elinor Karlsson of the University of Massachusetts.
“You can go to these websites and they will tell you, ‘If you want a dog that will be friendly to your children, you should get these breeds,'” Professor Karlsson said.
“But you could get a dog of one of those breeds and it happens to be a dog that doesn’t like kids.
According to the study, age or gender, rather than race, were the best predictors of behavior for some traits, such as activity level and toy play.
But there were still some subtle differences, with some breeds displaying more of traits that went back to their ancestral roots.
Once upon a time there were wolves
Dogs evolved from wolves thousands of years ago and were gradually chosen for skills such as hunting, guarding, or herding.
The notion of breeds – selection based on physical and aesthetic characteristics such as color, size and coat type – dates back only about 160 years to the Victorian era.
Qualities are attributed to modern breeds by organizations such as the American Kennel Club because of their ancestral roles as herders or hunters.
For example, Border Collies are described as “affectionate, smart, and energetic,” while Beagles are said to be “friendly, inquisitive, and cheerful.”
To find out if these stereotypes have a genetic basis, the team surveyed the owners of more than 18,000 dogs participating in a citizen science project called Darwin’s Ark.
Owners were asked a series of questions designed by dog trainers to find out how their dogs performed across eight categories such as were provoked by unpleasant stimuli (“agonistic threshold”).
“People are very good at letting us know about their dog’s behavior. They spend a lot of time watching their dog and if you ask them, they will tell you very precisely,” Professor Karlsson said.
The team compared this to DNA samples from 2,155 dogs.
While around 600 of the dogs were purebred, most involved in the sample were mutts, said lead author Kathleen Morrill of the University of Massachusetts.
The mutts also helped eliminate prejudice against breed stereotypes from owners, who were often unable to properly identify the mix of breeds in their dog.
But genetic testing can reveal what percentage of a breed a mutt carries.
For example, Jack (above) is a one-fourth American pit bull terrier.
The study found that breed explains only 9 percent of behavioral variation in individual dogs.
‘We basically showed that every behavior was seen in every single breed,’ said Professor Karlsson.
However, there were some traits that were more likely to be passed down through the generations of some dog breeds.
Border collies and mutts, with a higher percentage of border collies, were good at following directions, while beagles, bloodhounds, and Siberian huskies were more likely to howl than other dogs.
The team identified 11 spots on the genome that have been linked to behaviors such as howling and human socializing.
Many of these so-called motor traits, such as howling, pointing, fetching, and playing with toys, are throwbacks to the days when dogs evolved from wolves.
Is there an aggressive type?
Although a number of breeds, such as B. American Pit Bull Terriers, are banned or restricted in Australia, no breed in the study stood out as being aggressive.
“[Agonistic threshold] was actually the behavioral factor for which we found almost no evidence of racial differences,” said Professor Karlsson.
Instead, these behaviors appeared to be influenced by environmental rather than genetic factors.
“You could be born with the best genetics in the world, but if you don’t have the right experiences, like early puppyhood, it could completely change your personality,” she said.
What about working dogs?
The study included information on 78 companion dog breeds but did not address the behavioral traits of working dogs.
“These dogs are currently being selected to do a job, people don’t care what they look like,” Professor Karlsson said.
“We would expect to see a lot more behavioral differences in these populations,” she said.
But there have been very few iconic Australian working dogs like Kelpies in the owner database, she added.
It’s very difficult to study the genetics of behavior, said Claire Wade, an animal genetics expert at the University of Sydney who studies purebred Kelpies.
“We know that these complex traits are likely influenced by hundreds, if not thousands, of different genes,” Professor Wade said.
“There’s no question that there are a lot of differences between breeds, but I think it comes from so many places affecting each trait that it’s going to be difficult to pinpoint anything that’s biologically significant.”
There is a lot of care in it, just like nature.
“How many of these behaviors are innate – just like the dog – compared to trained behaviors?” Professor Wade said.
And the perception of a dog’s behavior can depend on the circumstances or where the dog is when it’s being observed.
Professor Wade said trying to tease out the answers to these questions would be even more difficult with mixed breeds.
“If you have important genes that affect something, are they dominant or recessive, are they influenced by the environment, are they masked by genes contributed by the other race?
“But if you throw big numbers at it [as they’ve done in the study]then you can end up finding some biological meaning, but I don’t think they’re there yet [in our understanding of the genetics of behaviour].”
Back at the dog park…
While the genetics of the behavior “still remain a mystery”, Professor Wade said the data collected in the study on how aging affects a dog’s behavior is very interesting.
“When they’re young they want to play with everyone, but that really goes away by the age of four or five. Then they end up not wanting to play with anyone.
“We kind of know this, but still we all drag our dog to the dog park and hope he gets along with most dogs.
“And what that shows is probably not true for most dogs.”