10 Disturbing Facts About Twins
1. Nearly half of identical twins develop their own secret language.
About forty percent of identical twins develop their own special coded form of speech that only they can understand. To outsiders, it sounds like babbling, but the twins comprehend it with perfect clarity. This phenomenon is known as “idioglossia” and helps twins plot to secretly take over the world. And if you think they’re talking about you, they probably are. A pair of teenage girl twins who went on a crime spree during the early 1980s were known as “The Silent Twins” because they never spoke to anyone else and only spoke to one another in their personal secret language.
2. Some conjoined twins can even hear each other’s thoughts.
Conjoined twins share the same body. As a result, they can often taste the same things and feel the same emotions at the same time. In cases where twins are joined at the head, they can often hear one another’s thoughts. This becomes especially problematic when one twin is thinking bad things about the other one.
3. One pair of twins can have two different fathers.
Although their mom will have a lot of explaining to do, about 1 in 400 pairs of fraternal twins are sired by different dads. If an ovulating women releases multiple eggs during a cycle and has sex with different men, this can result in what’s known as “heteropaternal superfecundation”—one mom, two dads, one pair of twins, and presumably very tense family reunions.
4. Identical twins who were separated at birth often end up leading very similar lives as adults.
Countless cases have been documented where twins who were separated at birth grow up to have nearly identical IQs, work in the same professions, and make almost the same amount of money. In some cases, they’ve even married women who have the same surnames or given their pets the same names.
5. Twin fetuses begin playing with one another in the womb at around 14 weeks.
Ultrasound images reveal that around 14 weeks after conception, twins begin reaching out to one another and touching one another. They have even been observed taking extra care not to poke one another in the eye. By week 18, they touch one another more often than they touch themselves. It has never been directly observed, but I suppose it’s even possible that some intrauterine twins have been known to thumb-wrestle.
6. Twins are taking over the country.
Since 1980, the rate of twin births in the USA has spiked 76%. This is partially attributed to the fact that women are waiting longer to become mothers, since there’s a strong correlation with a mother’s age and her likelihood of having twins. But if trends continue, the day will come when single babies are the exception rather than the rule.
7. Twins are twice as likely to be born left-handed than the overall population.
As if it wasn’t strange enough to be a twin, many of them also are left-handed, which in many cultures throughout history has been seen as a sign of demonic possession. Twenty-two percent of twins are left-handed, as compared to 10% of the overall population. Science still doesn’t have an answer for why this occurs.
8. If you want to tell identical twins apart, look at their belly buttons.
It is often nearly impossible to distinguish between identical twins…EXCEPT when you look at their navels. Your belly button is the result of how your umbilical cord is cut. It has nothing to do with genetics. An identical twin’s belly button is their “fingerprint.” Actually, “identical” twins also have different fingerprints, but you can’t tell the difference with the naked eye like you can looking at their navels. How you’ll get the chance to ever look at their navels is something you’re going to have to gently negotiate with them.
9. “Mirror” twins are exact reflections of one another.
About a quarter of identical twins develop in the womb while directly facing one another. As a result, they look like mirror images of one another. For example, if one twin has a mole under her left eye, her mirror twin will have the same mole under her right eye—just as she would if it was the same person staring in a mirror. If one “mirror” twin is left-handed, the other will be right-handed.
10. The “twin community” even has a slur for non-twins.
Although they probably don’t consider it a slur, the community of “multiples”—i.e., all twins, triplets, quadruplets, etc.—refers to single-birth children as “singletons.” It sounds a little bit too much like “simpleton” for this here singleton’s comfort. 
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