Identifying facial expressions in dogs: A replication and extension study

Abstract

This study replicated and extended previous research (Bloom & Friedman, 2013) indicating that humans can correctly identify emotional expressions in photographs of dog faces when tested with one breed (i.e., a Malinois). It examined the effect of dog facial morphology on accuracy of emotion identification by using images of a Malinois, as well as two-different breeds (Doberman and Rhodesian Ridgeback) expressing six-discrete emotions (happiness, sadness, anger, fear, disgust, surprise). Using a sample of 105-undergraduate students, participants were shown slides presenting four different expressive images of the same breed and asked to identify the image that best depicted one of the six emotions. Analyses indicated that participants were able to correctly identify all emotions across all dog breeds significantly better than chance, replicating the previous study for the Malinois, and extending its findings to additional breeds. Accuracy of emotion identification was predicted to be lower for the Doberman due to its darker coloration, possibly interfering with recognition of subtle emotional cues, but was found to be highest for the Malinois, followed by the Doberman, and then the Rhodesian Ridgeback.

Keywords: Canine; Communication; Emotion; Evolution; Facial expression; Morphology.