Personality traits in the domestic dog (Canis familiaris)

The domestic dog (Canis familiaris) has been subjected to a huge range of selection pressures during domestication that has resulted in a considerable diversity in morphology and behaviour. This, together with the many uses the dog is put to in our society, makes the dog an interesting model for studies of animal personality. However, only a few attempts have been done to study individual differences in dogs. In this study, behavioural data from 15,329 dogs of 164 different breeds were used to investigate the existence of personality traits in dogs. The data were collected at a personality test that tested the dogs' reactions to strangers, fleeing prey-like objects, and several potential fear- and aggression-eliciting stimuli. Factor analyses revealed the existence of five narrow traits: Playfulness, Curiosity/Fearlessness, Chase-proneness, Sociability and Aggressiveness. Higher-order factor analyses showed that all factors except Aggressiveness were related to each other, creating a broad factor that influences behaviour in a range of situations. Both narrow and broad factors were found in a dataset including data from a large number of breeds, as well as within eight of Federation Cynologique Internationale's (FCI's) 10 breed groups. This indicates that the personality dimensions found in the study are general for the dog as a species. The finding of a major behavioural dimension in different groups of dog breeds, together with comparable results previously found for wolves (Canis lupus), suggests that the dimension is evolutionarily stable and has survived the varied selection pressures encountered during domestication. The broad factor is comparable to the shyness-boldness axis previously found in both humans and animals, and to human supertraits (a combination of Extraversion and Neuroticism). The results of this study can be used to describe and compare individual dogs, as well as breeds. This, in turn, can be used in applications like selection of service dogs and breeding animals, as well as predicting behaviour problems in pet dogs. (C) 2002 Elsevier Science B.V. All rights reserved.