Object-directed behaviors and human-directed sociability are linked in free-ranging dog puppies

Most behavioral studies in dogs have investigated sociability and exploration of novelty as separate traits, often using different test settings and behavioral measures. However, this approach does not allow to assess whether these traits may instead reflect a shared underlying mechanism, such as a general tendency to approach novel stimuli, regardless of their social nature. In this study, we exposed pre-weaned free-ranging dog puppies to an unfamiliar human and a novel object. Free-ranging dog puppies were chosen to minimize the effect of experience and breed-selection biases. At 3 weeks of age, behaviors such as interaction, activity, and tail-wagging toward a novel object predicted similar behaviors toward a human, suggesting a unified trait rather than separate traits for sociability and object exploration. This challenges the traditional dichotomy between human-directed sociability and object exploration, proposing a common underlying mechanism. Nevertheless, puppies also showed more frequent behaviors with the social stimulus, likely due to greater sensitivity to animated stimuli.