Has your dog just always been naturally apprehensive of strangers, even aggressive toward them? Research published in the Journal of Veterinary Behavior suggests that there’s a link between dogs that show a left paw preference and aggression toward people they’ve never met before.
That’s right, dogs, just like humans, can be right-pawed, left-pawed, or ambilaterally pawed (favoring both paws equally). Although, while only a small percentage of humans are left-handed, about 10%, about half of all dogs show a preference for their left paws.
Following ideas hypothesized in the Valence-Specific Hypothesis which states that the right hemisphere of the brain is associated with negative emotion and the left hemisphere is associated with positive, researchers sought to determine if a relationship existed between paw preference and overall temperament. Because left-handed people are generally right-brained, and vice versa, it was assumed that the same hand/brain relationship exists in dogs.
To test for paw preference, 73 pet participants were given a Kong toy stuffed with food and observed while they held the toy. They were then rated on a scale from -100 (strong preference for using left paw) to +100 (strong preference for using right paw). Additionally, a temperament questionnaire was given to each pet parent.
While researchers found no evidence of a relationship between overall temperament and paw preference, they did find one interesting occurrence – those dogs with a high left-paw preference also tended to show a higher level of aggression toward strangers.
Research study co-author Dr. Luke Schneider, a post-doctoral research officer at the University of Adelaide in Australia, told The Huffington Post, “I reported a statistically significant relationship between stranger-directed aggression and the presence of a paw preference. Dogs without a paw preference demonstrated lower aggression scores. When I looked more closely at the dogs with a paw preference, it appeared that it was those dogs with a preference for the left paw that were driving this relationship.”
Schneider said this study shows that human and canine brains are much more alike than originally believed.
So, if your dog is naturally apprehensive of strangers, even aggressive toward them, it could simply be the way he’s wired!