If you were to encounter your lookalike on the street, would you recognize them, or would you pass them by without realizing it? This is a question that the Montreal-based photographer François Brunelle has spent the last few decades asking himself—and trying to answer—in his “I’m Not a Look-Alike” series of black-and-white photographs that feature people who look each other, and often don’t realize it or see it for themselves. And now his lookalikes portrait project has unearthed very interesting information on the DNA of these unrelated doppelgängers.

Brunelle first started his lookalikes portrait project in 1999 after discovering that he had his own lookalike—the British actor Rowan Atkinson (aka Mr. Bean!). At the time, facial recognition software was not advanced enough to use for research, so instead, Brunelle relied on interviews with media to scout people who looked like each other. Sometimes people knew each other because they worked in the same office, and were told by co-workers that they could be twins. Other times, they were matched via the thousands of emails Brunelle began to receive as the project gained in popularity. To pair subjects, Brunelle staged shoots in locations including New York, Los Angeles, Spain and Colombia, among many other places, and he continues to keep finding more lookalikes.

Each shoot begins with Brunelle meeting the doppelgängers. Often, they are surprised they are paired up. “I have a friend who came up to me before I started taking pictures, and said, ‘It’s just not true, I don’t look anything like this person,’” Brunelle recalls, laughing. Even if the eye can’t see the similarities, the camera can, he notes.

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Brunelle asks each of his subjects to arrive with three outfit choices in plain, black and muted colors. Then, together, they try to match tones so that in the photographs, the viewer can focus on the doppelgänger’s facial features. The subjects are often uncomfortable at first, notes Brunelle, especially if they are male strangers. To make them relax, Brunelle chats incessantly. “I’m a little crazy, and I talk a lot,” he says. “People look at me, and they say, ‘Who is this animal?’” At the same time, they let their guards down, and when they do, Brunelle asks them to stand closer together, and imagine that they are cousins living in different countries who have come together for a family reunion.

As the shoot progresses, Brunelle finds that the pair begin to resemble each other more and more. Brunelle uses a Phase One digital camera, a single softbox and a white reflector, and sets his subjects against a neutral background. Towards the end of the shoot, he asks his subjects to pose with their heads close together. “They look alike, so they start to act alike,” he notes. “The human in them begins to recognize this.”

Back in August, researchers from the Josep Carreras Leukaemia Research Institute in Barcelona, Spain, published a study in Cell Reports that began decades earlier after Dr. Manel Esteller saw Brunelle’s project and asked if he could study the genetic make-up of some of the participants. What Esteller and his colleagues found was astounding. Of the 32 pairs, 16 received the same overall scores to identical twins who were studied by the same facial recognition software. The 16 who resembled identical twins shared far more genetic similarities than the 16 that the software deemed less similar, even if they were from different parts of the world. What Dr. Esteller determined was that their genetic similarities were spurred on by human growth rather than some miraculous connection. The more humans there are in the world, the more DNA will randomly repeat itself, leading to every human alive having a doppelgänger—or a few—walking around at any given time.

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For his part, Brunelle was unsurprised by the data and even less surprised that people can’t necessarily recognize their doppelgängers when they come face to face with them. “If we had a clone walking around, would you recognize him?” he wonders. In fact, at the end of our conversation, he urged me to go look in the mirror. “I’ve talked your ear off,” he said. “You let your guard done. Go see what you look like.”

Brunelle continues to work on the lookalikes portrait project and is always on the lookout for doppelgängers. In the past, his goal was to publish the series in a book, as well as to show it in an exhibition context. “I thought a few thousand people would see it, and I would become the king of photography,” he laughs. Now, given the popularity of the project on the Internet, he surmises that millions of people have seen his work…and wonders how many of them will come face to face with their own lookalike.

As for the question of whether the pairs in his photographs really do look alike, Brunelle surmises, “Does it matter what [I] think?” “It’s [my subjects] who speak,” he says. “Not me.” What he implies is that even if the subjects are not identical, looking at them closely reveals similarities. As they might if you paired any two people close together and took a photograph of them. A human face, after all, is not that complex— a set of eyes, a nose, a mouth, a chin. Given the physical material that comprises a face, it’s no wonder that we don’t encounter our doppelgängers more frequently, he says. This explains, in part, the popularity of the series. As unique as we may feel, we know that somewhere, there’s someone, or many people, who look just like us, and what does that say about who we are as individuals? To wonder if there’s someone out there who’s exactly like us is inherently human.