Mutual gazing by dogs but not wolves increases oxytocin levels in humans.
For many people dogs are considered to be family members and their best friends. Indeed, because of the long period of close association between dogs and humans, a deep bond has evolved (for numerous references and discussion please click here).
While the existence of this co-evolved and special bond is a given, researchers have also been interested in what might mediate this close connection and if a similar relationship exists between wolves, from whom dogs have emerged, and humans. And now, some important light has been shed on these questions. A paper published this week by Miho Nagasawa and his colleagues titled "Oxytocin-gaze positive loop and the coevolution of human-dog bonds" in the prestigious journal Science shows that indeed, there is something unique about human-dog bonds. The summary and conclusions of their essay, available now online, read as follows.
Human-like modes of communication, including mutual gaze, in dogs may have been acquired during domestication with humans. We show that gazing behavior from dogs, but not wolves, increased urinary oxytocin concentrations in owners, which consequently facilitated owners' affiliation and increased oxytocin concentration in dogs. Further, nasally administered oxytocin increased gazing behavior in dogs, which in turn increased urinary oxytocin concentrations in owners. These findings support the existence of an interspecies oxytocin-mediated positive loop facilitated and modulated by gazing, which may have supported the coevolution of human-dog bonding by engaging common modes of communicating social attachment.