Dogs' personalities can change, research suggests

Feb. 25 (UPI) -- Most longtime pet owners would likely agree that dogs can have distinct personalities, and research has shown those personalities are shaped by their owners.

Now, new findings out of Michigan State University suggest dogs' personalities change over time.

Life-changing events can transform human personalities. The results of a new survey, published in the Journal of Research in Personality, showed similar types of changes can affect dogs.

"We expected the dogs' personalities to be fairly stable because they don't have wild lifestyle changes humans do, but they actually change a lot," lead study author William Chopik, professor of psychology at Michigan State, said in a news release. "We uncovered similarities to their owners, the optimal time for training and even a time in their lives that they can get more aggressive toward other animals."

Chopik and his colleagues surveyed the owners of 1,600 dogs. The survey included 50 different breeds and included puppies, as well as dogs young and old. Owners answered questions about their own personality, their dog's personality and their dog's behavioral history.

"We found correlations in three main areas: age and personality, in human-to-dog personality similarities and in the influence a dog's personality has on the quality of its relationship with its owner," Chopik said. "Older dogs are much harder to train; we found that the 'sweet spot' for teaching a dog obedience is around the age of six, when it outgrows its excitable puppy stage but before its too set in its ways."

Owners who rated their own personality as agreeable described their own dogs friendlier to and less fearful of other people and animals. Owners who described themselves as extroverts were more likely to rate their dogs as excitable and active.

The survey showed that a dog's personality could change over time. Researchers linked personality changes to dogs' exposure to their owners and training.

"Exposure to obedience classes was associated with more positive personality traits across the dog's lifespan," Chopik said. "This gives us exciting opportunities to examine why personality changes in all sorts of animals."

The research is good news for dog owners who want to improve their relationships with their animals. Owners who described the positive relationships with their dogs were more likely to rate their pets as active and excitable.

In addition to the quality of the owner-dog relationship, researchers found a canine's personality can also predict its biting history and chronic illness.

In follow up studies, Chopik hopes to more closely examine the different events and actions that can encourage transformations in a dog's personality.

"Say you adopt a dog from a shelter. Some traits are likely tied to biology and resistant to change, but you then put it in a new environment where it's loved, walked and entertained often. The dog then might become a little more relaxed and sociable," Chopik said. "Now that we know dogs' personalities can change, next we want to make strong connection to understand why dogs act -- and change -- the way they do."