The exceptions that prove the rule? Spontaneous helping behaviour towards humans in some domestic dogs

Domestic dogs (Canis familiaris) are skilled at reading and correctly responding to human communicative gestures to locate hidden food. Whether they, like chimpanzees, will understand requests for help in retrieving a fallen object, is not known. The aim of this study was to examine whether dogs show spontaneous helping behaviour towards a human experimenter that tries to obtain an object that is out of reach. The object at stake either “accidentally” fell on the floor, or was thrown on the floor by either a familiar (owner) or unfamiliar human. In order to get a better understanding of individual differences between helping and non-helping dogs, the behaviour of all dogs was observed by means of continuous focal animal sampling and scored by means of an ethogram. Personality traits were measured by letting owners rate their dogs on 50 personality adjectives using a 7-point Likert scale. The results demonstrate that six out of 51 dogs showed helping behaviour and did so more in the accidental (experimental) condition, than when the object was thrown on the floor on purpose (control) condition (P = 0.001). Dogs in general wagged their tail more (P = 0.009) and looked less often towards the test leader (P < 0.001) in the experimental condition compared to the control condition, suggesting that they experienced more arousal whenever humans were in need of help. In addition, a principal component analysis indicated to retain 41 adjectives which revealed five personality factors, in line with previous research, that accounted for 60.7 % of the total variance. However, the six exceptional dogs had no outstanding personality traits and were of different breeds suggesting that this did not explain the differences in helping behaviour. We conclude that dogs appear motivated and willing to help humans, but that the majority does not understand the source of the problem or how to assist. We discuss this result in light of the previously reported social skills of dogs and nonhuman primates.