Familiar Dog or Familiar Person: Who Do Pet Dogs Best Synchronize with?

Behavioural synchronization in dogs has been examined separately at intraspecific and interspecific levels. This study is the first to compare dogs' behavioural synchronization and gaze behaviour when with a familiar person (with FP) compared to a familiar dog (with FD), while walking in an outdoor environment. Twenty dogs were observed under the two experimental conditions. We hypothesized that dogs would demonstrate stronger location and activity synchronization with an FD than with an FP due to similar locomotor patterns, while showing greater gaze attention towards the FP compared to the FD. Our hypothesis was partially confirmed. The results revealed a significantly shorter distance between dogs and the FD than between dogs and the FP. Dogs exhibited a smaller speed difference with the FD than with the FP, but only if they did not cohabit with other dogs. No significant differences were observed in body alignment or gaze behaviour between the two experimental conditions. Our results point to behavioural synchronization as a new instance of evolutionary convergence, as well as daily experiences, here cohabiting with other dogs, as a factor influencing dogs' ability to synchronize with individuals from different species. This study enhances our understanding of canine cognition in conspecific versus heterospecific contexts.