Selective overimitation in dogs.

Dogs have not only shown different kinds of social learning, from either conspecifics or humans, including do-as-I-do imitation, deferred imitation, and selective imitation, but in two previous studies they have also shown an eagerness to copy causally irrelevant actions. This so-called overimitation is prevalent in humans but is totally absent in great apes. Whereas in one of two previous studies dogs copied actions from an experimenter (Johnston, Holden, & Santos in Developmental Science, 20, e12460, 2017), in the other a reasonable number of the dogs copied the irrelevant actions from their human caregiver (Huber, Popovová, Riener, Salobir, & Cimarelli in Learning & Behavior, 46, 387-397, 2018). Dogs have not only been domesticated to live and work with us, but many companion dogs develop strong affiliative relationships with their caregiver, which are akin to the attachment bonds between human children and their mother. We therefore assumed that overimitation in dogs might be strongly motivated by social factors, such as affiliation or conformity. To test this hypothesis, we confronted dogs with the same demonstration of causally relevant and irrelevant actions as in the previous study (Huber et al. in Learning & Behavior, 46, 387-397, 2018), but this time with an unfamiliar experimenter instead of the caregiver as the demonstrator. The results strongly supported our hypothesis: Whereas half of the subjects in the previous study replicated the causally irrelevant action demonstrated by their caregiver, only very few did so when the actions were demonstrated by the experimenter. We conclude that the eagerness of dogs to learn from humans and to copy even unnecessary actions is strongly facilitated by their relationship with the particular human.