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Does Genetics Determine a Dog's Personality?

Research shows that much of a dog's personality is determined by its genes.

Psychologists use the word “personality” to mean those characteristics a person displays that allow us to predict how they will behave, react and feel in various situations. Some scientists, however, are uncomfortable about using the word personality when talking about non-human animals. They use the word “temperament” instead. Although the average person will see little difference between the two terms, using a different label allows the scientist to suggest that there are still significant qualitative differences between the behaviours of people and animals.

But what is personality? What leads to personality differences among breeds? What leads to differences in personality even among individuals within the same breed? Biology teaches us that there are two main ingredients that contribute to making all of us what we are: genetics (“nature”) and the environment (“nurture”). In dogs a large proportion of their personality is due to their inherited genes.

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Consider, for example, the group of breeds that we call Spaniels. Most dog breeds are named after the place that they originated or the person who created the breed. Spaniels are named after Spain (español) yet none of the Spaniel breeds were created there. So where does the name come from? One aspect of the behavior of Spaniels that particularly impressed people who encountered these dogs was their temperament. In general members of the Spaniel breeds are much friendlier and more "kissy-faced" than many other breeds. At the time these breeds were first becoming well known, it was believed that the greatest lovers and most romantic people in the world were the Spanish. So to highlight that loving temperament, which is a genetically transmitted aspect of all of these breeds, these dogs were given a label recognizing what was perceived as their Spanish temperament, if not their actual Spanish origin.

Of course the case in Spaniels deals with popular perception, however science has also looked at the issue of genetics and personality. The interaction between genes and temperament was explored by Jasper Rine of Berkeley, among others, as part of the Dog Genome Project that is mapping the genetic code of dogs. Rine began his research with a Border Collie named Gregor (after Gregor Mendel, the 19th-century monk credited with some of the earliest insights into the science of genetics) and a Newfoundland named Pepper (because she is black) who were then bred to each other.

Rine chose Border Collies and Newfoundlands not only because they are physically different but because they have very different personalities. Newfoundlands are easygoing and affectionate dogs, protective of people, loyal, not easily startled by noises or distracted by things going on around them. They are not overly active and would rather walk than run. Border Collies are much the opposite. Although friendly enough, they are far more devoted to their work than to the people around them. They are intense and focused, yet easily upset by sudden, attention-grabbing events going on around them. When you enter a room, a Newfoundland may nudge you, asking for attention and affection; a Border Collie is more likely to acknowledge your arrival with a glance, then return to his task of trying to herd the cat.

Gregor and Pepper’s puppies (called the “F1” generation) were given personality tests. The five indicators that the project looked at were: demand for affection, excitement barking, startle response, sociability with other dogs, and likelihood of staring or “showing eye” (a dominance behaviour, especially strong in Border Collies, that they use to exert influence over the animals that they are herding-- and also people if they can get away with it).

When it came to the personality of the puppies, they fell somewhere in the middle relative to their parents—more affectionate and easygoing than their Border Collie father, but more intense and excitable than their Newfoundland mother. However, when members of the F1 generation were mated to each other (to create the F2 generation), the personality traits began to sort themselves out in unpredictable ways. One of the F2 puppies seemed to be very demanding of affection and not easily startled (both Newfoundland personality characteristics), but was not very sociable around other dogs, was prone to excitement barking, and used lots of threat stares (Border Collie personality traits). Another pup was very affectionate with people and sociable with other dogs (Newfoundland characteristics), but made lots of dominant eye contact and startled easily (Border Collie traits). Yet his barking was an average of the characteristics of his grandparents, more than a Newfoundland but less than a Collie.

The 23 members of the F2 generation exhibited just about every possible combination of the personality characteristics of their grandparents. These characteristics had averaged out in the first generation Newfoundland and Collie crosses (their F1 parents). But as the genes recombined in this second generation, some breed-specific characteristics emerged again in recognizable form and strength, but in combinations never observed in their purebred grandparents.

This research not only demonstrates the nature of genetic control of dog personality characteristics, but also has implications for breeders of so-called “designer dogs” such as so-called Cockapoos, Labradoodles and Goldendoodles. If, for instance, the aim is to create a dog with a blend of the characteristics of the Labrador Retriever and the Poodle, this will only reliably occur in a first-generation breeding of purebred parents. Subsequent generations can be quite unpredictable in both temperament and physical characteristics.

Stanley Coren is the author of many books including: Born to Bark; Do Dogs Dream? The Modern Dog; Why Do Dogs Have Wet Noses? The Pawprints of History; How Dogs Think; How To Speak Dog; Why We Love the Dogs We Do; What Do Dogs Know? The Intelligence of Dogs; Why Does My Dog Act That Way? Understanding Dogs for Dummies; Sleep Thieves; The Left-hander Syndrome

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