Sure enough, Turcsan found that the dogs and their owners both tended to show similar personality profiles. “It was actually higher than the similarity found in married couples and friends,” she says. Importantly, the correlation couldn’t be explained by the amount of time the dogs and their owners had spent living together, so it didn’t seem that the dog had simply learnt to ingratiate itself by copying the owner. Instead, the personality seemed to be part of the dog’s appeal in the first place. Perhaps it’s wise that we choose these companions to be so compatible: the average dog does, after all, outlive the average marriage.
It is awe-inspiring to think of how this relationship first emerged. Humans started domesticating dogs as much as 30,000 years ago to help us with hunting, but slowly we have bred these creatures in our own image, allowing us to forge an intense emotional bond that crosses the natural boundaries between our species.
Today, they look like us, act like us, and – unlike other humans – they always reciprocate our feelings. In many ways they are the better reflections of our own true natures. It’s little wonder we now consider them man’s best friend.
David Robson is BBC Future’s feature writer. He is @d_a_robson on Twitter. Gerrard Gethings is a London-based photographer who has specialised in portraying the distinctive personalities of animals.
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