By Kim Gilliam 

We are all familiar with the idea that our personalities change as we age. Oftentimes, we become more mellow or more agreeable as we age. The same is true for dogs, however, some traits do stay the same over time, according to recent research from the Clever Dog Project at the University of Vienna. For example, researchers found some dogs are just born as old souls with personalities that are relatively steady and mature throughout their lives.

How do you measure a dog’s personality? In this case, 217 border collies from half a year to 15 years old were observed as they responded to 15 different tests designed to assess 70 personality traits such as exploration, obedience, problem solving, compliance, threat reaction, frustration and play. Tests included attention from a stranger, being dressed in a t-shirt by their owner, a sausage dangled just out of reach, ball play and more.

Four years later, 37 dogs returned for retesting. The researchers found that the dogs changed as they aged, just as people do, becoming less active and less anxious.

At least we all know how to calculate a dog’s age in human years, right? Just multiply it by seven. It’s actually not quite that simple.

A study out of the University of California, this time of 104 Labrador retrievers, found that to calculate dog years, you should multiply the natural logarithm of a dog’s age in human years by 16 and then add 31.

What now? This may require a calculator. Let’s see what it equates a dog age 6 to. The natural log of six is around 1.8; multiply this by 16 to get 29, then add 31 and they would be 60 in human years.

To reach this conclusion, researchers sought patterns of chemical changes in DNA, a process called methylation. Lab tests can tell how old a human is just from this, and now, thanks to this research, the same can be done for dogs.

Some parts of a dog’s life follow the same pattern as humans, while other longevity milestones are not in synch. For instance, the methylation rate in a 7-week-old pup corresponds to a 9-month-old human baby, and both begin teething at this time. But then the dog clock ticks much faster, with pups racing through puberty and hitting sexual maturity within a year. The dog’s genetic clock slows down as they age, matching up with humans again in later years. In this way, a 12-year-old lab is on par with a 70-year-old human.

A study published in The Royal Society’s Biology Letters also found that adolescent dogs share some of the characteristics of adolescent humans, including “reduced trainability and responsiveness to commands.”

All of this builds on a 2019 study by Michigan State University, published in Journal of Research in Personality, the first and largest study of its kind to examine changes in dogs’ personalities. It surveyed owners of more than 1,600 dogs – across 50 different breeds ranging from a few weeks to 15 years old – on their dogs’ personalities and behavioral history. The owners also answered a survey about their own personalities. The findings were enlightening.

Not surprisingly, older dogs proved harder to train, whereas dogs around age 6 were much better at learning obedience when they’re out of the excitable puppy stage but not too set in their ways. It turns out it is harder to teach an old dog new tricks.

One trait that rarely changed with age was fear and anxiety. Along the lines of “dogs resemble their owners,” the research showed dogs and owners share specific personality traits. Extroverted humans rated their dogs as more excitable and active, while owners high in negative emotions rated their dogs as more fearful.

The study’s findings show just how much owners influence their dog’s personality. In many cases, the changes in a dog’s personality are the result of the nature versus nurture theory associated with humans’ personalities.

That’s a lot to digest, but hopefully it provides some insight into how your dog’s personality develops and ages over time. Make sure to enjoy quality time with your pup, no matter what phase they are in.

The writer co-owns Frolick Dogs, an indoor dog gym in Alexandria, with her husband, Kevin Gilliam.