What Science Says About Your Chances Of Having A Doppelgänger Or 'Twin Stranger'
Should you be on the lookout for your evil twin?
Litvinov / Shutterstock By Theo Harrison
Is there someone in the world who looks exactly like you? Is it even scientifically possible to have a doppelgänger?
With over 7 billion people in the world, it just might be possible that someone resembles you.
What is a doppelgänger?
Doppelgänger is a German word that literally translates to "double-walker." In a general sense, the term is widely used to mean someone who physically resembles you, but is not related to you.
To put it simply, a doppelgänger is a non-biologically related lookalike, someone who is not genetically connected to you or your family, yet they have oddly similar physical features.
Although today, the word may mean a twin stranger or a double, traditionally a doppelgänger referred to our alter ego or our ghostly counterpart, and seeing one could lead to misfortune and bad luck. However, according to some traditions, a doppelgänger may also mean an evil twin.
“Folk wisdom has it that everyone has a doppelgänger; somewhere out there, there’s a perfect duplicate of you, with your mother’s eyes, your father’s nose and that annoying mole you’ve always meant to have removed,” writes science journalist Zaria Gorvett for BBC.
She adds, “We live on a planet of over seven billion people, so surely someone else is bound to have been born with your face? It’s a silly question with serious implications — and the answer is more complicated than you might think.”
According to paranormal researcher and author Stephen Wagner, doppelgängers have been traditionally considered as sinister and evil entities. Hence, there is a lot of superstition surrounding the concept.
It has been found that most reports of doppelgänger sightings are nothing more than cases of mistaken identity.
However, Wagner explains, “such an explanation becomes harder to accept when they are seen by best friends, siblings, and parents who know the real person intimately. It seems hard to believe that they would be fooled by another person who simply resembles the original.”
Whether just a lookalike or a paranormal being trying to steal your life, the question that needs to be answered is this:
Are doppelgängers real? Do you really have a doppelgänger somewhere out there?
Despite all the folklore, literature, and horror movies, it is highly unlikely that you have a doppelgänger who looks exactly like you, at least according to science.
According to a 2015 study by researchers Teghan Lucas and Maciej Henneberg in Australia, there is only a one in 135 chance that there’s an exact pair of complete doppelgängers in the world.
The study analyzed the probability of 2 different unrelated individuals matching up in 8 key facial features.
However, the research revealed that having a twin stranger or an exact identical lookalike, involving all the 8 facial features, is only one in 1 trillion.
Dr. Teghan Lucas, a forensic anthropologist at The University of New South Wales, who assessed over 4,000 faces from the US Anthropometric Survey (ANSUR) and measured 8 distinct facial features, explains, “If we are talking about measurements of the face, there is a 1 in a trillion chance that 2 or more people will match one another on 8 measurements of the face.”
The chances of finding a doppelgänger became even slimmer when Dr. Lucas analyzed the rest of the body for similarities.
She adds, “If we look at measurements of the body, the chance is even lower at 1 in a quintillion based on 8 measurements. This is because these measurements are larger and thus have a larger range, which means there is less chance for people to match each other.”
So despite how similar a stranger may look to us or our friends and family, it is highly unlikely that someone will be exactly similar to another person in the true sense of the word doppelgänger.
Dr. Lucas says, “Two people may look very similar to the naked eye, but when you start measuring they will not match each other.”
Why do some people look alike?
Although you may be less likely to meet an exact doppelgänger, some people do tend to look alike. If we learn to ignore the mathematics and facial details, the probabilities of having a doppelgänger or a lookalike become a lot higher.
Assistant professor of neurobiology and behavior, Michael Sheehan, explains, “There is only so much genetic diversity to go around. If you shuffle that deck of cards so many times, at some point, you get the same hand dealt with you twice... There’s only so much variation out there. Some people will happen to look similar.”
However, it’s not just about facial similarities. Sheehan says, “It’s not only facial appearance but also styling, how people are presenting themselves or acting. Context has a lot to do with looking alike as well.”
Having said that, the amount of genes that decide the human appearance and the shape of our ears, nose, and lips is “incredibly voluminous.”
Professor of molecular and human genetics, Dr. Arthur Beaudet says, “There’s a huge number of genes that contribute to things like facial structure and, of course, hair, eye, and skin color, which are all highly variable.”
So although an American and Asian might not be identical lookalikes, individuals from the same race and ethnicity do share a lot of similar genes. Beaudet adds, “You find two people from similar descents who probably do, in fact, have a fair amount of genetic sharing when you go way back.”
Moreover, the wide range of human appearance is not limited to only 8 facial traits. BBC’s Zaria Gorvett explains that the study conducted by Dr. Teghan Lucas was based on exact facial measurements.
“If your doppelgänger’s ears are 59 mm but yours are 60, your likeness wouldn’t count. In any case, you probably won’t remember the last time you clocked an uncanny resemblance based on the length of someone’s ears,” she writes.
The likeliness of finding your doppelgänger also depends on exactly what you mean by the term. Statistician David Aldous of U.C. Berkeley explains, “It depends whether we mean ‘lookalike to a human’ or ‘lookalike to facial recognition software’.”
According to a recent study by Sheehan, a professor of neurobiology at Cornell University, our eyes play a crucial role in social interactions. Hence, we have evolved to look as physically unique and different from one another as possible.
Most animals rely on their sense of smell to identify and differentiate each other; humans, however, primarily depend on sight to recognize different individuals.
The researchers found that we are exceptionally good at identifying people and recognizing faces. Yet, when we look at a stranger, we tend to find similarities with someone we know.
Believing you have seen a doppelgänger of someone else or even yourself may also be due to your mind playing tricks on you. This is what psychologists call the perceptual experience.
We tend to become familiar with certain facial features and traits of our loved ones since our childhood. Caucasians become attuned to noticing subtle differences in eye color and hair color, whereas African-Americans become accustomed to subtle shadings in skin tone.
Psychology professor, Christian A. Meissner, explains, “It’s a product of our perceptual experience. The extent to which we spend time with, the extent to which we have close friends of another race or ethnicity.”
Hence, we often believe that people from different races, especially not from our own, tend to look similar.
The human mind is complex, to say the least. What we believe to be a doppelgänger of someone just might be our inability to distinguish the subtle differences in their facial features between the original and double. However, this could also be a result of mental disorders as well.
Is it all in the mind?
Capgras delusion, also known as imposter syndrome, is a psychological condition where an individual irrationally believes that an identical-looking imposter has replaced someone they know. They may believe that a family member or even their romantic partner has been replaced by a doppelgänger, which may lead to problems in the relationship.
Unlike other mental conditions, Capgras delusion doesn’t affect other aspects of your life, except for the belief that an imposter has replaced your loved one. People with this mental disorder believe that the imposter looks exactly like the actual person and only they can identify the disguise of the imposter.
Another variant of the Capgras delusion, Fregoli syndrome, can also make some people believe in the existence of doppelgängers. It is a rare mental disorder that makes someone believe that different individuals are actually the same person who constantly changes their disguise or appearance.
According to a 2006 study, people with delusional misidentification syndromes (DMS), like the Fregoli and Capgras syndromes, tend to have “identifiable brain lesions, especially in the right frontoparietal and adjacent regions, in a considerable proportion.”
This has been revealed by neurophysiological and neuroimaging studies. The study concluded that, “Deficits in working memory due to abnormal brain function are considered to play causative roles in DMS.”
Apart from these, there might be a much simpler explanation behind the mystery of seeing doppelgängers.
Forensic scientist and facial recognition expert, Dr. Daniele Podini of George Washington University in Washington, D.C., believes that how we look at faces is greatly influenced by our own experiences and context.
When two individuals wear the same clothes or have the same haircuts with similar physiques, we tend to believe that they look alike, due to confirmation bias.
It is a cognitive bias and a psychological tendency to seek, interpret, prefer, and recall details that verify, support and confirm our personal values and beliefs. It allows our minds to adjust certain facts to fit familiar and expected patterns.
So, are doppelgängers real?
It depends on your perception and what you believe to be true.
Although we may have similar-looking doubles or lookalikes, having an exact doppelgänger or an unrelated identical twin stranger may be less likely.
So even though some of your friends may believe that they saw someone who looks “exactly” like you, the possibility of having an evil twin trying to take over your life is highly unlikely.
So the next time you see someone who looks the same as you or your friend, simply smile and greet them. You just might make a new (not evil) friend.
Theo Harrison is an artist, traveler, writer, former contributor to The Mind's Journal, and believer in spiritualism, psychology, and science. He writes primarily about mental health, pop culture, and relationships.