Identifying meaningful vocalizations in nonhuman animals can help explain the evolution of human communications. However, non-speech-like sounds, including laughter equivalents, are not well studied, although they may be meaningful. In this pilot study we investigate whether dogs perform a domain-specific pant during play by capturing vocalizations and behaviors during three interactions: training, play, and rest. Sixteen human and dog dyads participated in a session that included all three interactions in the same order: training, play, rest. During these sessions, each partner wore wireless microphones that transmitted to a receiver and digital recorder, while a standalone digital camera captured video of the interactions. A one-way ANOVA demonstrates that dogs do perform a domain-specific play pant, which was almost completely absent during training and rest. These vocalizations mostly co-occurred with play behaviors (e.g., play bow) or tickling and cuddling. These preliminary findings suggest that a laugh-like play pant is used by dogs during play; future research should explore other interspecific acoustic signals as derived from conspecific signals and having communicative function
