Dogs (Canis familiaris) distinguish conspecific emotional chemosignals

Abstract Emotional communication facilitates social interactions among animals. While dogs can discriminate and exhibit context-appropriate behaviors in response to odor samples from stressed and non-stressed humans, their capacity to differentiate emotional odors from conspecifics—and the broader function of these cues in intraspecific communication—has not been investigated. Using a habituation-discrimination paradigm, 43 dogs were presented with odor samples from an unfamiliar dog collected after events marked as joyful, stressful, and baseline (relaxing). Subjects showed longer investigation time for novel versus repeated odors, indicating successful discrimination and dishabituation. Specifically, subjects distinguished between joy and baseline odors and between joy and stress odors. Additionally, dogs exhibited distinct behavioral responses depending on the emotional content of the odor, including differences in stress- and joy-related behaviors, proximity to targets (owner, stranger, and odor source), and body posture. Exposure to stress odors elicited the predicted attachment-related behaviors—characterized by increased proximity to their owners and reduced proximity to strangers—suggesting a response to conspecific emotional states that may reflect emotional contagion. These results demonstrate that dogs can perceive and behaviorally respond to emotional odors from conspecifics, underscoring the role of olfaction in canine intraspecific emotional communication.