According to a recent study, The Pace of Life Under Artificial Selection: Personality, Energy Expenditure, and Longevity Are Correlated in Domestic Dogs, there is a link between personality, metabolic rate, and life history traits. Researcher Vincent Careau and his colleagues conclude that dogs of obedient, docile and shy breeds live longer than breeds that are more typically bold or disobedient. They also found that aggressive breeds have higher energetic needs than breeds who are not typically aggressive. It is well known that large dogs don’t tend to live as long as small dogs. This study corrected for size and found that personality is related to canine life span without allowing size to confound their conclusions.
Some specifics of the study’s findings are that both the German Shepherd and the Bichon live a long time for their size, and that Labradors and Newfoundlands burn less energy for their weight than other breeds. On the other end, Fox Terriers, Great Danes, Beagles and Pomeranians had short life spans relative to their size. The basic idea is that dogs who expend a lot of energy and don’t live that long are consistent with a pace-of-life syndrome that goes with a “live fast, die young” model. It has been used to explain varying life spans of a number of species.
The scientists who conducted this study assert that these results could be a result of either humans selecting for particular combinations of traits, but they believe another possibility is more likely: They think that these correlations probably arose from inadvertent correlations of these traits with the trait humans were truly selecting for—personality.
Many people will no doubt find this study fascinating, but there are already critics who view dogs as an unusual case in that the smaller breeds tend to live longer whereas in other animals, the longest-lived animals tend to be bigger. I myself am curious about how the breeds were categorized as bold, obedient, docile, aggressive etc. What do you think about this study?