Bodily emotional expressions are a primary source of information for dogs, but not for humans

Abstract

Dogs have remarkable abilities to synergise their behaviour with that of people, but how dogs read facial and bodily emotional cues in comparison to humans remains unclear. Both species share the same ecological niche, are highly social and expressive, making them an ideal comparative model for intra- and inter-species emotion perception. We compared eye-tracking data from unrestrained humans and dogs when viewing dynamic and naturalistic emotional expressions in humans and dogs. Dogs attended more to the body than the head of human and dog figures, unlike humans who focused more on the head of both species. Dogs and humans also showed a clear age effect that reduced head gaze. Our results indicate a species-specific evolutionary adaptation for emotion perception, which is only partly modified for heterospecific cues. These results have important implications for managing the risk associated with human–dog interactions, where expressive and perceptual differences are crucial.

Functionally analogous body- and animacy-responsive areas in the dog (Canis familiaris) and human occipito-temporal lobe

“…Thus, human and dog stimuli appear to be equally salient for dogs. This is in line with previous behavioural studies suggesting, for example, no significant difference in the perception of human or dog emotional facial [34], whole-body cues [77], or images of social interactions [67].…”

“…The absence of a further sub-specialization for face vs. body perception in the occipito-temporal cortex of dogs might indeed indicate that dogs in comparison to humans focus more on whole body social cues rather than on specific sub-parts. This interpretation is notably well in line with a recent comparative eye-tracking study [78].…”

“…Thus, human and dog stimuli appear to be equally salient for dogs. This is in line with previous behavioural studies suggesting, for example, no significant difference in the perception of human or dog emotional facial [35], whole-body cues [78], or images of social interactions [68]. Further, two studies demonstrated that dogs, already as puppies, follow human gestural-communication and show an interest in human faces [76], which has not been observed in wolf puppies [79].…”

Heads and Tails: An Analysis of Visual Signals in Cats, Felis catus

“…We showed that visual configurations used by cats when interacting with other cats or with humans differed greatly: in cat–cat interactions, the position of the ears appeared to be the most significant feature and when approaching humans, usually only one visual configuration is used, featuring the tail up. Correia-Caeiro et al [ 44 ], dealing with dog–humans interactions, made the important point that what is important for one species might not be so for another one, especially when very phylogenetically distant.…”

“…In interspecific interactions, each species has to adapt and adjust to the communicative repertoire of the other species. Humans in particular may learn through associative learning the meaning of the signals given by their pets [ 44 ] Ear or tail positions are easily perceived by humans and interpreted. Artificial selection in cats has been less active than that in dogs [ 49 ].…”