Paw Behaviour: Why Pet Dogs' Traits May Have Little To Do With Their Breed

From sociable labradors to aggressive pitbulls: when it comes to canine behaviour, there are no end of stereotypes. But research suggests such traits may have less to do with breed than has long been believed.

- Nicola Davis

Modern breeds began to emerge in the Victorian era and are often physically distinct: for example, great danes are huge and chihuahuas tiny. But it has often been thought that breed can predict behaviours, too. Now researchers in the US say there is little sign that this is the case.

Dr Elinor Karlsson, of the University of Massachusetts Chan medical school, a co-author of the study, said research had revealed a huge diversity of behaviour within each breed. "Even if the average is different, you've still got a really good chance of getting a dog that doesn't match what people say that breed is supposed to be."

In the journal Science the researchers report how they analysed surveys on physical traits and behaviour of 18,385 pet dogs, almost half of which were purebred, and analysed the genetic data of 2,155 of them.

Analysis of the results for purebred dogs suggested about 9% of behavioural variation was explained by breed. "For the most part, we didn't see strong differences in breeds, but there are some [behaviours] that are connected to breed more than others," said Karlsson.