We’ve all been on the receiving end of it: a wishful dog peering out from under the table gives you his best shot at puppy eyes as you lift a forkful of chicken into your mouth. We’ve loved reporting on the various ways dogs have evolved to cohabitate with humans, and especially how some characteristics reflect the species keen adaptation to our human ways. The newest research on the matter hasn’t let us down, so we knew we’d share with our readers…

A few weeks ago, a team of researchers at the National Academy of Sciences reported that dogs make puppy eyes — that look of quizzical anticipation — more frequently than wolves. In fact, officially coined “AU101: inner eyebrow raise” the look we so often see as a dog cocks its head may be a result of clever evolution and positive reinforcement. The proof is in the pudding here; dogs have evolved to have muscles above their eyebrows that make for a more expressive face, while wolves, despite having similar muscle construction, don’t lift their eyebrows. This bit of domesticated biology has been working in dog’s favors, perhaps passing the favorable trait down through the generations. For example, an expressive dog with puppy eyes is more likely to be adopted from a shelter, and in studies conducted on human preference, research has shown that people prefer pets which infant like features — such as wide, hopeful eyes — a characteristic that kicks our “nurturing” instinct into gear. Puppy eyes aren’t the only way dogs continue to steal our hearts – according to other research in the field, both human and dog share a boost of Oxytocin when reunited, the love hormone that reinforces bonds and keeps our canines so loyal.

All this to say, we’re happy these lovable companions continue to choose us and our couches over the wild woods!