How the Shape of Your Dog's Head Influences His Behavior

brachycephalic breed

Story at-a-glance -

  • An Australian study suggests the shape of a dog’s head has a tremendous impact on his behavior
  • Researchers concluded short-nosed dogs like the Pug and English Bulldog are more affectionate, trainable and defensively aggressive (protective) than dogs with longer muzzles
  • Their appealing looks, behavior and trainability have made short-muzzled breeds an “obsession” of dog lovers in Australia
  • Unfortunately, poor breeding practices designed to exaggerate facial features have subjected many short-nosed (brachycephalic) dogs to numerous health problems and abbreviated lifespans
  • It’s time for breeders, kennel clubs and owners of brachycephalic dogs to reverse the current trend toward breeding strictly for looks, with no regard for the health of these wonderful dogs

By Dr. Becker

Recently, researchers in Australia set out to test the theory that the way a dog looks (its “morphology”) influences its behavior. Past studies have revealed, “… as height and weight decrease, many undesirable behaviours (non-social fear, hyperactivity and attention seeking) become more apparent.”1

Translation: the smaller the dog, the more likely he or she is to be fearful, high strung and needy. While we know this applies to some small dogs, like all generalizations of this sort, it certainly doesn’t apply to every small dog.

A lot has to do with how well the puppy is socialized and whether he receives positive training throughout his lifetime. There are plenty of 5-pounders who are self-assured and independent, just as there are lots of shy, clingy big dogs.

But back to the Australian study. Whereas past similar studies were based on dog owner surveys, this study involved trained observers and data from over 60,000 dogs and 45 different breeds.

Short-Nosed Dogs Have Become an Obsession in Australia

The results obtained from the study generated some rather interesting media headlines, including this one from ABC News Australia, which caught my eye:

“Snub-nosed dogs more affectionate and make better guard dogs, study suggests”2

Like the ABC News piece, several media articles about the study, which was published in the journal PLoS One,3 suggest these positive attributes in dogs with short muzzles (brachycephalic breeds) may explain the growing “obsession” with short-nosed breeds in Australia, despite their significant health problems.

In recent years, animal welfare experts in Australia and the U.K. have grown increasingly concerned that brachycephalic dogs (e.g. the Pug, Boston Terrier, Boxer, Bulldog, etc.) suffer many health challenges due to the construction of their heads and faces, and most don’t live as long as dogs with longer muzzles.

However, kennel clubs often promote dogs with highly exaggerated physical features. That means in the case of brachys, the flatter the face, the more likely the dog is to be favored by show judges. This encourages breeders to produce dogs with ever-shorter muzzles, without concern for the health of the animals.

According to the researchers, one of the reasons for the most recent study was to try to understand why, despite their health problems, the brachy breeds continue to be so popular in Australia and the U.K. According to Professor Paul McGreevy, Ph.D. of the University of Sydney and a co-author of the study:

"If people accept short-skulled dogs are likely to cost more, suffer health problems and die earlier, then there must be something else that gets people across the line.

Yes the dogs look cute, but I think it's their beguiling behavior that compensates for the disadvantages of owning them.”4

Study Suggests a Dog’s Head Shape Strongly Impacts His Behavior

The researchers concluded the shape of a dog’s skull “strongly influences” behavior. They found short-nosed dogs were more likely to be affectionate and follow commands than dogs with longer muzzles.

The brachys also showed more interest in chasing toys dragged on the ground, which suggests they may be easier to train.

(My opinion differs from the researchers’ conclusions in that I think all dogs are trainable and the earlier you start, the easier it is. Some dogs may pose more training challenges, but most animals respond to positive reinforcement.)

When they felt threatened, the short-muzzled dogs “… were more likely to have the characteristics of a good guard dog — demonstrating defensive aggression such as biting, barking and lunging at a human standing under a sheet, or a cardboard cut-out of a human.”5

According to McGreevy, dogs with longer faces responded in an opposite fashion, showing shyness, caution and less aggression toward strangers. “This helps explain why Greyhounds don't generally excel as guard dogs and Afghans tend to be aloof, less playful and more fearful than shorter-skulled dogs," he said.

(For the record, I suspect the researcher’s use of the term “guard dog” is simply a way to describe the protective instincts many dogs naturally display in situations they perceive as threatening.)

Another observation made by McGreevy is that brachys may be more appealing to humans because the unusual shape of their head means their eyes are more forward-facing and further apart than the eyes of dogs with longer noses.

He also theorizes their eyesight is “more like a human’s,” and they seem to be better able to follow a pointing finger than dogs with longer skulls.

Brachy Breeds Deserve Long, Healthy Lives, Too

The researchers believe their study results show there is more to our love of brachys than just their cute appearance. They also state that while flat-faced dogs may display some particularly appealing behaviors, the growing concern over their health should give us pause.

One example of poor breeding practices that have been disastrous to the health of the breed includes the modern day version of the English Bulldog, who suffers from an endless list of diseases. According to one survey, the median age of death for this breed is 6.25 years.

The massive size of today’s English Bulldog often makes normal mating and birthing out of the question. Most can’t reproduce without medical intervention.

Another example is the Pug, a brachycephalic dog that has been bred to exaggerate the short-nosed trait. The result? High blood pressure, heart problems, low blood oxygen levels, breathing problems, a tendency to overheat/develop heatstroke, dental issues and skin fold dermatitis.

As a veterinarian, I’ve seen first-hand the problems created when dogs are bred exclusively to achieve a certain look, without concern for their health, mobility or quality of life.

It is deeply troubling to me, with all we know about the suffering these animals endure, that breeders persist in exaggerating their dogs’ physical characteristics, even if it means sacrificing their health.

Fortunately, at least one kennel club has acknowledged it’s a bad idea to encourage poor breeding practices with the goal of exaggerating a dog’s physical characteristics to the point of compromising his health. According to McGreevy:

"The Norwegian Kennel Club has said that because of the health problem in short-skulled dogs, they're going to change the breed standards so the dogs won't be so short-skulled after all.”6

In Australia and the U.K., the increasing popularity of brachycephalic breeds appears to be in response to their cute looks and personality, as well as their trainability. However, as McGreevy points out, "We also want long-lived dogs and we're not getting that if we follow this trend.”