Dataset of paper: "Dogs (Canis familiaris) recognise our faces in photographs: implications for existing and future research"

Dogs are an ideal species to investigate phylogenetic and ontogenetic factors contributing to face recognition. Previous research has found that dogs can recognise their owner using visual information about the person’s face, presented live. However, a thorough investigation of face processing mechanisms requires the use of graphical representations and it currently remains unclear whether dogs can spontaneously recognise human faces in photographs. To test this, pet dogs (N = 36) were briefly separated from their owners and, to achieve reunion, they needed to select the location indicated by a photograph of their owner’s face, rather than that of an unfamiliar person concurrently presented. Photographs were taken under optimal and suboptimal (non-frontally oriented and unevenly illuminated faces) conditions. Results revealed that dogs approached their owner significantly above chance level, with no difference in the probability of choosing the owner between the optimal and suboptimal conditions. Only in the suboptimal condition did the amount of attention paid to the owner’s photograph affect dogs’ choices, with low attention associated with failures. The probability of approaching the owner was also affected by an interaction between the dog’s sex and condition, although no significant effect was detected in post-hoc comparisons. This study provides the first direct evidence that dogs can recognise human faces from photographs. The results imply that motion and three-dimensional information is not necessary for recognition. The results also support the ecological valence of such stimuli and increase the validity of previous investigations into dog cognition that used two-dimensional representations of faces.