Similarities and differences of face and body perception in the dog (Canis familiaris) and human brain

Accurately recognizing other individuals is fundamental for successful social interactions. While the neural underpinnings of this skill have been studied extensively in humans, less is known about the evolutionary origins of the brain areas specialized for recognising faces or bodies. Studying dogs (Canis familiaris), a non-primate species with the ability to perceive faces and bodies similarly to humans, promises insights into how visuo-social perception has evolved in mammals. We investigated the neural correlates of face and body perception in dogs (N = 15) and humans (N = 40) using functional MRI. Combining uni- and multivariate analysis approaches, we identified activation levels and patterns that suggested potentially homologous occipito-temporal brain regions in both species responding to faces and bodies compared to inanimate objects. Crucially, only human brain regions showed activation differences between faces and bodies and partly responded more strongly to humans compared to dogs. Moreover, only dogs represented both faces and dog bodies in olfactory regions. Overall, our novel findings revealed a prominent role of the occipito-temporal cortex in the perception of animate entities in dogs and humans but suggest a divergent evolution of face and body perception. This may reflect differences in the perceptual systems these species rely on to recognize others.