In studies where a stranger approach was taken, the wolves exhibited more avoidance behavior compared to dogs, and instances of aggression were more common in pet dogs. Researchers, Friederike Range and Sarah Marshall-Pescini of the Konrad Lorenz Institute of Ethology at the University of Veterinary Medicine in Vienna wrote, “Only in tests involving access to resources did four of 16 wolves consistently show aggression toward humans, while none of the 11 dogs did. Studies using a stranger’s threatening approach found more avoidance behavior in adult wolves than in dogs and more occurrences of aggression in (pet) dogs.” Overall, these findings indicate differences in how the wolves and the dogs react to resource related situations and threatening approaches. The wolves displayed more aggression in resource-related tests and the dogs showed more aggression in response to threatening strangers.
