"We compared the propensity to take risks in a foraging context between wolves and dogs that had been raised under the same conditions," said lead author Sarah Marshall-Pescini, post-doctoral student at the University of Vienna in Austria.
The study found that wolves prefer the risky option significantly more often than dogs.
When faced with the choice between an insipid food pellet and a fifty-fifty chance of either tasty meat or an inedible stone, wolves nearly always choose the risky option, whereas dogs are more cautious.
"This difference, which seems to be innate, is consistent with the hypothesis that risk preference evolves as a function of ecology," Marshall-Pescini added.
In the study, the team let each of seven wolves and seven dogs choose 80 times between two upside-down bowls, placed side-by-side on a movable table-top.
The animals had been trained to indicate the bowl of their choice with their paw or muzzle, after which they would receive the item that was hidden beneath it.
The team had taught the wolves and dogs that beneath the first bowl, the "safe" option, was invariably an insipid food pellet, while beneath the second bowl, the "risky" option, was either an inedible item, a stone, in a random 50 per cent of trials, and high-quality food, such as meat, sausage, or chicken, in the other 50 per cent.
As a control, the side for the "safe" and "risky" option changed between trials, but the animals were always shown which side corresponded to which option; whether they would get a stone or high-quality food if they chose the "risky" option was the only unknown.
Wolves chose the risky option in 80 per cent of trials, whereas dogs only did so in 58 per cent of trials, the researchers said, in the paper published in the journal Frontiers in Psychology.
Wolves depend on hunting for survival with a success rate of between 15 and 50 per cent, whereas free-ranging dogs (which make up 80 per cent of the world dog population), are largely scavengers specialised on human produce (i.e., a more geographically and temporally stable resource).
Dogs must have evolved a more cautious temperament after they underwent an evolutionary shift from their ancestral hunter lifestyle to their present scavenger lifestyle, which happened between 18,000 to 32,000 years ago when humans first domesticated dogs from wolves, the researchers stated.
Thus, dogs no longer need to take risks when searching for food, and this may have increased their preference to play safe, Marshall-Pescini noted.
