From Mary-Kate and Ashley Olsen to mythological twins Romulus and Remus credited with founding the city of Rome, twins have captured the human imagination across the millennia.
Some say that spotting your doppelganger or look-alike is a harbinger of bad luck. Others say a doppelganger is your evil twin. But it’s not all bad. Shakespeare’s Comedy of Errors is the story of twins separated at birth. A hilarious case of mistaken identity ensues when the long-lost twin brother returns to town.
However you regard identical twins, many wonder whether twins can spoof biometric authentication systems. After all, identical twins come from the same fertilized egg and they share the same DNA. So it really depends on which biometrics are used. It’s true that identical twins can fool a facial identity system. But forensics experts say identical twins do not share identical fingerprints.
Fingerprints consist of patterns of arches, loops, and whirls. While twins’ fingerprints may have similarities in patterns, they differ in the minutia. Minutia are the tiny details of fingerprints and these form while fetuses are in the womb. The exact detail of ridges along these patterns is influenced by many factors including bone growth, pressures within the womb and contact with amniotic fluid.
Identical twins might fool people, but when it matters most, fingerprints can tell them apart. Even in perfect, look-alike twins, their irises are different.
What’s interesting is if we look at the factors that affect our fingerprints over time as well, you could see that even in the most extreme science fiction scenario, even an evil twin from another dimension would have slightly different fingerprints. As we age, wear and tear from working with our hands and scars from cuts will factor into our prints, adding new unique characteristics. While our doppelganger from another dimension might have been born with the same prints, they wouldn’t have the same life experiences to leave those new flaws.
Take that, bearded doppelganger.
The point is, we can rest easy about fingerprint spoofing. In order to replicate someone’s fingerprint, you can’t just track down someone who looks really similar. This is why fingerprints are a much more secure biometric than facial recognition. Anti-spoofing technologies, such as liveness measures, help to ensure that copies and forgeries of your fingerprints can’t be used against you as well. In this way, fingerprinting provide the ultimate tool for security and convenience that we need for modern authentication.