Consistently, the oxytocin levels of both the dogs and the humans were higher at the end of the sessions—and usually by about the same percentage for each owner-dog pair. But it was among the pairs in which there was a lot more gazing and a lot less touching and talking that the levels were highest—high enough to cross the threshold of statistical significance. None of this was true in the wolf-human pairs.

“The duration of the dog-to-owner gaze…significantly explained the oxytocin-change ratio,” the investigators wrote.

In the second experiment, the investigators similarly collected before-and-after urine samples from dog-human pairs. But this time, either oxytocin or an inert solution was administered to the dogs nasally before the interactions began. Each dog was then released into a room with its owner and two strangers, and though the dogs typically approached their owners and nuzzled them, the humans were instructed neither to talk to the dogs nor touch them back, but simply to meet their gaze.