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Big dogs, Small dogs
Does size affect behavior?
Big vs Small Dogs

He chose the dog, but I chose the name,” the woman explained. Their dog was an especially petite Boston Terrier, but his name — Titan — was one more typically bestowed on a larger dog. I’d seen this type of incongruity before, and though it’s sometimes just for the sake of being ironic, often it’s about conflict. Couples who disagree about whether to add a large dog or a small dog to their family compromise by choosing a dog of one size and a name that’s usually given to a dog of another size. I’ve also met Pixie the Newfoundland, Tank the Bichon Frise, Bitsy the Bouvier and Goliath the Pug.

People often have strong opinions about what size dog best suits them. Some prefer small dogs because they’re more likely to be welcome everywhere, especially when traveling, while others gravitate to large dogs because they associate them with fun and friendliness, as well as kids and families. Sizebased biases are also common, and sad to say, I’ve heard a number of derogatory terms for both small and large dogs. And anyone with big dogs knows that people sometimes fear them even when their behavior is exemplary and a small dog is present whose behavior is not. One Bark reader implored me, “Don’t forget to cover that big dog stigma!”

Many people have asked the question, “How is the experience of having a large dog different than that of having a small dog?” Part of the answer may come from evaluating whether big and small dogs really are different in ways that extend beyond size, particularly in their behavior. Another piece of the puzzle involves determining if people’s behavior toward and expectations of dogs varies based on the dog’s size.

A Sizeable Spectrum
One of the marvels of domestic dogs is the astounding range of sizes they come in, which is determined by a very small number of genes. (In comparison, roughly 200 gene regions affect height in humans.) A dog’s size has practical consequences — just ask anyone with a Great Dane suffering from diarrhea, an experience that’s not the quite same for a person with a similarly afflicted Maltese. Likewise, dealing with a seven-pound Affenpinscher who prefers not to get into the car may require nothing more than matterof- factly picking her up and putting her inside. The situation is far more challenging when a 185-pound Saint Bernard’s involved. Big dogs can be more expensive in every way, from the cost of food, professional grooming and medication to toys, leashes, collars and food bowls.

People with little dogs who don’t want them to help themselves to food simply avoid picnicking on the floor and are careful not to leave chairs where they can be used as stepping stones to the table or counter. People with large dogs often find that no place lower than the top of the refrigerator is safe or truly off-limits. With a large dog, the accidental consumption of dangerous foods, such as chocolate, is far less likely to lead to serious consequences than for a smaller dog because it takes much more for the dose to be toxic to a larger dog. Similarly, the few extra treats that lead to weight gain in smaller dogs may be no big deal for a large dog. Finally, helping a large dog with mobility issues can be physically demanding for the caregiver.

Some worry about big dogs around children, but I must confess that I worry when we dog-sit a friend’s sixpound Pomeranian. My kids are gentle with him and do a good job of being kind and respectful, but I’m still worried that they’ll collide with him and cause an injury completely by accident, no matter how actively I’m supervising. With bigger dogs, that isn’t as much of a concern.

Many people point out the advantages of small dogs in urban environments: it’s easier to rent an apartment (weight limits favor them); tight living spaces may be easier to share; and getting small dogs into and out of an apartment building, especially while you’re housetraining them, is far less of a challenge. Yet traits that can be troublesome for urban living — high exercise needs, sound sensitivity, a tendency to bark excessively — have nothing to do with size. Some dogs are beautifully suited to life in the city, and others are not.

So, are behavioral differences sizebased? For the most part, the answer is a resounding “No!” Dogs of all sizes love to play chase, fetch, go on walks, run off leash, meet new people, romp with their best dog buddies, participate in training sessions and eat tasty treats. By the same token, dogs of all sizes are vulnerable to sound sensitivity, exhibit separation anxiety and aggression, jump on people inappropriately, bark to excess, chew on shoes, dig in the garden, or have accidents on the floor. They all wag their tails (if they have them!) in joy.

And yet, there are clearly differences between individual dogs, based perhaps on age, gender or the environment in which the dog lives and was raised. While the similarities in dogs of different sizes are far greater than the differences, can we deny those differences?
Should we?

Science Steps In
A 2010 research study (Arhant, et al.) examined the connection between size and behavior in great detail, addressing these questions: How does guardian behavior toward dogs of unequal sizes influence their dogs’ behavior? How do expectations of dogs based on their size differ? Do people treat large and small dogs differently? In the study, “small” and “large” were defined by weight; dogs less than 20 kg (44 pounds) were categorized as small and those equal to or more than that, as large.

The study’s most important overall finding? There are significant differences in behavior between large and small dogs and between guardians of large and small dogs. The researchers reported that a range of interactions between people and their dogs are related to the size of the dog.

Small dogs were reported to be less obedient, slightly more often aggressive or excitable, and more anxious and fearful. People with small dogs also reported a lower level of consistency in their interactions and enforcement of rules than did those with larger pups.

Much has been made of the practice of treating small dogs like babies, though it’s hardly surprising that it occurs. Babyish features affect human caretaking behavior; we’re evolutionarily hardwired to find big eyes, small size and proportionally large heads endearing. Psychologists call this the “Aww phenomenon.” If babies weren’t so cute, parents could be less likely to respond to their needs, and the offspring would be less likely to survive.

Dogs seem to elicit this same “aww” response in humans, especially small dogs, and even more so, breeds with pronounced juvenile features such as Cavalier King Charles Spaniels, Chihuahuas, Japanese Chins, Pugs and Boston Terriers. Since babies affect our hormones, raising the levels of oxytocin — nicknamed “the love hormone”— it stands to reason that adorable dogs do, too.

Socialization, Training and Other Interactions
Socialization is a key factor when it comes to dog behavior. Typically, large dogs have more opportunities for socialization than small ones. When small dogs are carried around rather than moving around on their own four paws, they have fewer interactions with people and other dogs, which can limit their ability to cope with them. Also, small dogs are often picked up or otherwise physically manipulated, which may result in more negative experiences with humans.

Many say that their small dogs are “people” dogs and don’t like other dogs; lots of people with big dogs say the same thing. Size notwithstanding, positive experiences with other dogs during puppyhood are the best way for a dog to develop good manners. Absent enough of those experiences, dogs of all sizes face social challenges.

Well-trained dogs are always a joy, but training is another way in which interactions between people and dogs differ based on size. Two research studies found that small dogs do not receive as much formal training as large dogs (Kobelt, et al.; Masters and McGreevy). Also, people play fetch more often and do more tugging and nose work with big dogs than with small ones, and are more likely to take them running or biking (Arhant, et al.). Arhant’s study concludes that differences in people’s behavior may account for the higher rates of disobedience in small dogs.

Codes of Conduct
It’s hard to make the case that a dog’s size has no bearing on what we consider acceptable, or what we allow them to do. Though many guardians have the same rules for dogs of any size, the code of conduct for large and small dogs is often different.

For example, small dogs are more likely to be allowed in our beds and on our laps (Westgarth, et al.). Practical considerations are at work here. Having a 25-pound dog jump or sit on you is one thing, but having a 100-pound dog do it is another. Others encourage little dogs to jump up on people and get on the furniture, but rarely invite big dogs to do so. Jumping up isn’t the only thing that’s treated differently. The behavior that is considered a nuisance in a small dog may be deemed antisocial in a large dog. Even aggression and other serious behavioral issues are more likely to be tolerated in small dogs.

As evidence that some people with small dogs don’t take undesirable behavior seriously, consider this story: an eight-pound Chihuahua escaped from his home, bit someone and was declared a dangerous dog. When a representative from animal control came, the dog’s people apparently thought it was a joke. One of them was reported to have said, “I broke out laughing. I said, ‘Look at the dog, do you see the dog going after you?’ The guy kind of got upset when I started laughing at him.”

For years, I have specialized in cases involving aggressive dogs, and to be honest, the size of the dog sometimes makes a difference in how I feel about the threat they represent. I once had a very aggressive Dachshund in my office, followed by a Chesapeake Bay Retriever with similar issues. During both appointments, I employed all the cautions necessary in this line of work. Still, throughout the appointment with the Chessie, I was aware of being afraid, while with the Doxie — though I knew I was at risk of being bitten if I made a mistake — I just didn’t feel the same anxiety. Both dogs were equally aggressive, but the size factor affected my fear response.

I’m not alone in reacting differently to aggressive dogs based on their size. Large dogs are more likely to be euthanized for aggression (Reisner, et al.), though another study (Guy, et al.) found that the average “biter” tended to be a smaller dog. It’s possible that greater tolerance for this behavior in small dogs allows genetic tendencies toward it to persist.

In some ways, there are correlations between size and breed characteristics. Many small dogs are terriers and earthdogs, types that have been deliberately developed to be tenacious and curious as well as to dig and explore. If dogs are bred for those characteristics, such behavior will have far more to do with genetic inf luences on behavior than with size.

Also related to breeding, Arhant, et al. found that small dogs were more likely than large dogs to come from pet stores, which generally acquire their “stock” from puppy mills. When you consider that puppy mills are notorious for environmental deprivation and risky breeding practices, it is perhaps no surprise that small dogs are burdened with more problematic behavior..

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What dogs do — their behavior! — is what makes them good company, great friends and essential members of our family, and very little of that has anything to do with size. When dog people swap stories, they are not about the size of the dog, but about the experiences we have in common — the joy, the angst, the training, the vet emergencies, the photos, the occasional chewed shoe, the games, the walks, the friendship, the fun and the love. It’s always a big love, no matter what size the dog.

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This article first appeared in The Bark,
Issue 70: Jun/Jul/Aug 2012

Karen B. London, PhD, is a Bark columnist and a Certified Applied Animal Behaviorist specializing in the evaluation and treatment of serious behavior problems in the domestic dog.

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Submitted by Angela Robinson | July 13 2013 |

What is the percentage of small dogs versus large dogs in America or the World?

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