Source: Nature (Extract)
Posted: May 4, 2022

Muttley crew: dog breeds are all about beauty, not behaviour

Dog enthusiasts have long assumed that a dog’s breed shapes its temperament. But a sweeping study comparing the behaviour and ancestry of more than 18,000 dogs finds that although ancestry does affect behaviour, breed has much less to do with a dog’s personality than is generally supposed.

“When you adopt a dog based on its breed, you’re getting a dog that looks a certain way,” says study co-author Elinor Karlsson, a computational biologist at the University of Massachusetts in Worcester. “But as far as behaviour goes, it’s kind of luck of the draw.”

For millennia, human efforts to shape dogs’ looks and behaviour focused on the animals’ working ability — how well they herded livestock, for example. Then dog enthusiasts in Victorian England began actively selecting for canine traits that they found aesthetically pleasing, leading to today’s breeds. Contemporary pure-bred dogs are defined by their looks, but breed is also thought to influence temperament.

To see how breed affects behaviour, Karlsson and her colleagues surveyed thousands of dog owners about their pets’ backgrounds and activities. The researchers then sequenced the DNA of a subsection of the survey dogs to see whether ancestry could be linked to behaviour (K. Morrill et al. Science 376, eabk0639; 2022).

The team found that some traits were more common in certain breeds. For example, compared with a random dog, German shepherds were more easily directed; beagles, less so. The genetic data revealed that mixed-breed dogs with a certain ancestry were more likely to act in specific ways. Mutts with St Bernard heritage, for example, were more affectionate; mutts descended from Chesapeake Bay retrievers had a penchant for wrecking doors.

But, on average, breed explained only around 9% of behavioural variation, a figure “much smaller than most people, including me, would have expected”, says Karlsson. Particularly low was the link between breed and how likely a dog was to display aggression. That could have implications for how society treats “dangerous” dog breeds, says Evan MacLean, a comparative psychologist at the University of Arizona in Tucson who was not involved in the study.

error: Content is protected !!