The idea that two people in a long relationship begin to look alike is an enduring one, but new research suggests it's simply not true. A team at Stanford used photos of 517 couples in their study at Scientific Reports, comparing images from when they first got together with those from much later on, between 20 and 69 years later. More precisely, they had volunteers assess the photos, as well as facial-recognition software. The result? Zero evidence that the couples changed to resemble each other. The research debunks a widely cited study from the 1980s, though one that was based on just a dozen couples, per the Guardian. Over the years, psychologists have generally backed up the assertion, arguing that everything from a shared diet to the amount of time spent outdoors were factors.
"This is definitely something the field needs to update," says Stanford's Michal Kosinski. "The field is filled with concepts and theories that are reclaimed, over-hyped, or not validated properly." So how to explain those couples who unmistakably bear a resemblance to each other? They started out that way. The study found that people were more likely to bear a resemblance to their significant others—compared to random people—at the start of their relationships. The researchers' conclusion is that people tend to choose partners who look like them, reports the Times of London. As examples, the story cites the famous pairings of Benedict Cumberbatch and Sophie Hunter, as well as Brad Pitt and Jennifer Aniston. (Read more discoveries stories.)