The Cool Science Of Doppelgangers (And How To Find Your Stranger Twin)

Niamh Geaney (left) found her doppelganger in Karen Branigan (right). Can you find yours?  (Photo: Courtesy of Twin Strangers)

Is there a stranger out there somewhere that looks exactly like you?

That’s what Irish friends Niamh Geaney, Terence Manzanga and Harry English set out to solve in 28 days. The trio set up a Facebook, Twitter, Instagram and YouTube account with one question: Do you know someone that looks like us?

Niamh Geaney, Terence Manzanga and Harry English, founders of Twin Strangers. (Photo: Courtesy of Twin Strangers)

“On the first day, I spent from 10 a.m. to 2 a.m. just asking my friends to share this, knowing at least a third of their friends would see it,” Geaney told The Washington Post of the endeavor known as the “Twin Stranger” project. “The power of social media is so crazy, so intense, you would not believe it.”

The messages soon poured in – thousands at a time – with more requests to help people find their doppelgangers, or people who look remarkably similar to them. And there were just as many messages that claimed to know someone who looked like the three project creators.

The most remarkable: Geaney met her own doppelganger, Karen Branigan, who lived just an hour away from her Dublin home. The pair was amazed at their similarities. “She can crack her entire back and I can do the same,” Geaney told the Post. “We both loved drawing growing up, and what did we both draw all the time? Fairies. We both used to draw fairies. That’s insane.”

Niamh Geaney and her found her doppelganger Karen Branigan. (Photo: Courtesy of Twin Strangers)

Actually it’s not that insane, according to Richard E. Lutz MD, Associate Professor of Pediatrics and Clinical Geneticist of the Munroe-Meyer Institute at the University of Nebraska Medical Center. He says that the pair shares physical similarities because they’re genetically similar and likely share a similar ancestral background.

“They come from the same basic population,” he tells Yahoo Health. “What it boils down to is this: You might find someone who lives thousands of miles away who looks like you, but if you look at your ancestral background you’ll find you originally came from the same place. Not surprisingly, if you come from a similar ancestral background you’ll likely find common characteristics – stature, eye color, even temperament.”

As for Gearney’s personality similarities to her doppelganger? Daniele Podini, a forensic molecular biologist at George Washington University, told the Post that it has to do with environment.

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“You can take two identical twins and raise one near the equator and one in Greenland,” Podini told the Post. “They will have different diets, physical activity, sun exposure and temperature at which they live, and so on, and that is going to affect their development.”

Dr. Lutz disagrees.

“Environment does make a difference, but it should be regarded as your culture,” he tells Yahoo Health. “What you eat, what you do for entertainment, how you speak – that’s influenced by the environment you live in.”

Heredity, Dr. Lutz says, will override any differences in environment, especially when it comes to twins. He cites the Minnesota Twin Family Study as the perfect example of the power of heredity over environment. In the study, Thomas Bouchard and other researchers from the University of Minnesota followed 137 pairs of twins – 81 pairs of identical and 56 pairs of fraternal twins – over several years.

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Jack Yufe (left) and Oskar Stohr (right), twins who were raised in different environments, but look identical. (Photo: Minnesota Twin Study)

One pair of twins studied, Oskar and Jack, were born in Trinidad but raised in drastically different environments: One was taken to Germany and raised as a Catholic Nazi youth. The other was raised in the Caribbean as a Jew. But when they were reunited they found they had distinct similarities: They both wore wire-rimmed glasses and mustaches, stored rubber bands on the wrists and liked to read magazines from back to front. They were also approximately the same height and weight.

The reason? Their quirks were built into their DNA.

“It’s the same reason why my brother and I have similar neck problems,” adds Dr. Lutz. “We have drastically different lives and careers, but we both have the same disc problems because of the genetics involved.”

As for unrelated doppelgangers?

“It’s a fun little social game to find people who are similar to you,” says Dr. Lutz, adding that it ultimately comes down to having a similar DNA background going back hundreds of years.

“You’re not going to go to a village in the heart of Rwanda and find someone like you if you’re from Scandinavia,” he says. “It just isn’t going to happen.”

Bottom line: Your genetics are the predominant factor that influences your looks and personality, while your environment or culture affects the rest.

As for your doppelganger? There is likely someone out there somewhere that looks and acts like you — and that person is probably closer to you, both location-wise and ancestral background-wise, than you think.

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