We have all heard those amazing stories about twins separated at birth, raised apart, unaware that they are twins, who then happen to be re-united later in life. On average, identical twins tend to be around 80 percent the same in everything from stature to health to IQ to political views. Evidence from the comparison of twins raised apart points convincingly to genes as the source of a lot of that likeness. identical twins are roughly 85 percent similar for IQ, fraternal twins about 60 percent. On average, identical twins raised separately are about 50 percent similar in IQ. Some stories:
View slideshow: Twins in Utero and Grown Up
James Arthur Springer and James Edward Lewis are twins who were reunited at age 39 after being given up by their mother and separately adopted as 1-month-olds. Springer and Lewis, both Ohioans, found they had each married and divorced a woman named Linda and remarried a woman named Betty. Each was interested in mechanical drawing and carpentry; their favorite school subject was math, their least favorite subject was spelling. They smoked and drank the same amount and each of them got headaches at the same time of day.
Oskar Stohr and Jack Yufe were twins born in Trinidad and separated from each other when they were six months old. Oskar was brought up Catholic in Germany and joined the Hitler Youth. Jack grew up in the Caribbean, was raised as a Jew and lived for a time in Israel. When the twins were reunited in their fifth decade they found that they had similar speech and thought patterns, similar gaits, a taste for spicy foods and common peculiarities such as flushing the toilet before they used it, and always keeping several rubber bands on a wrist.
Victor McKusick was treated at Massachusetts General Hospital for an infected arm. Victor developed a dental abscess. His brother, sailing up from Maine to join him, had to make an emergency shore call after developing the same problem.
Born on a Maine dairy farm in 1921, Victor and his twin, Vincent, both displayed remarkable brain power that enabled them to climb to the peaks of their respective professions. At 13, Victor was treated at Massachusetts General Hospital for an infected arm, and emerged several weeks later with the certainty that he would make his career in medicine. Vincent, who managed to stay out of the hospital as a kid, went on to Harvard Law School and eventually became chief justice of the Maine Supreme Court.
In both men one senses a polite but adamantine intelligence and a genius for organization. They are similar in height and weight -- about six feet, 180 pounds; similar in their soft-spoken but intense speech patterns and mannerisms.
Still, "there were differences in the two of us right from the beginning," says Victor. All through their childhood, Vincent usually took the lead, Victor usually followed. As to what accounts for that, Vincent defers to his brother, and Victor is too careful a scientist to venture a guess. Perhaps it had to do with the random movement of the neurons as they migrated to the brain stems of the weeks-old McKusick fetuses. Perhaps it was a "runting effect" -- the tendency of one identical twin to suck up womb nutrition to the detriment of the other. Or perhaps the differences in identical twins can be explained by the expectations of parents and siblings, desperate to find some way to tell the twins apart.
One woman named Gilia Angell recalls wandering into the St. Patrick's Cathedral gift shop in New York and buying a postcard of an airbrushed Jesus, which she mailed to her twin sister in Olympia, Wash. A few days later, she says, a letter postmarked the same day arrived from Olympia. Enclosed was a refrigerator magnet "with the same filmy airbrushed picture of Jesus!"
Impact of Genetics
These sort of stories suggest that genetics plays a larger role in determining who we are than we may think. Indeed scientists have made some pretty remarkable claims recently about the impact of particular molecules on behavior. In journals such as Science and Nature Genetics, researchers suggest that there are genes for neuroticism and thrill-seeking and risk-taking, genes for alcoholism and aggression and anxiety. In 1993, a National Cancer Institute researcher reported the location -- on chromosome X, as it happens -- of a gene that seemed to cause homosexuality. But these suggestions are far from proved.
Do genes really make homosexuals or violent kids or depressed adults? No reputable scientist would claim that they do. Genes make proteins that contribute to chemical pathways that play a role in complex neurological and existential events. But that's a long story, and a long way to go. But it is indisputable that there appears to be a desire within some of us, perhaps a "fatalism" gene? –that makes us want to believe that the genetic blueprint holds the secrets of who we are. Perhaps it is a cop-out, relieving us of responsibility for who we have become.
Sensitivities Of Twins to Each Other
Twins tell uncanny stories of wordless understandings, of moments of grief or joy communicated at a distance without benefit of a phone, by some kind of genetic magnetism, or twins who can sense when the other one is in danger. Then there are those twin pranks, adding to our general sense of wonderment over their doubleness -- duped boyfriends and confused motor vehicles officials, cheating on SAT tests -- and the good twin/bad twin dichotomies, exemplified by Jeen Han, a California 23-year-old who was recently convicted of trying to kill her twin.
Separateness of Twins
On the other hand, there is also no doubt that twins don't have to be told they are separate individuals -- they know it. "You could take 50 cells from my leg and make 50 other people who look and sound like me, but they won't be me," says Richard Bausch, a novelist, short-story writer and George Mason University writing instructor. "To any twin, the idea that human clones would be the same is absurd. When you're a twin you know that. People are much too complicated to be replicated, no matter how many genes they discover." This is no doubt true and felt by each twin, but also not probative regarding the twins phenomenon.
But Richard Bausch's convictions seem undercut by his biology. He may be accused of protesting too much. So Richard’s identical twin, Robert, is also a fiction writer, and also a writing instructor, at Northern Virginia Community College in Woodbridge. Robert is the more intellectual one; Richard is more religious. Their views on cloning is similar. Would they be different if they were not identical twins? Robert's analogies are Jesuitic. "If everything that we call the will is just genetics and chemistry," he asks, "then who in the hell are we talking to when we try to remember something that's on the tip of our tongue?"
The Bausch twins see less of each other these days than they used to. They each have their own work and their own children to worry about. They have been profiled too often to really enjoy being a novelty act anymore. Neither feels that being a clone is what defines him. But Richard will say this: "How people react to life is determined by their nature, but I don't think nature is biological. I still believe in good and evil, and that there is such a thing as sin.”
Life Experiences As A Twin
How would it feel to share 100% of your DNA with someone else and be pressured by everyone to perform the same in school, in sports, and in various other aspects of your lives?
Ben and Nathaniel Ludewig (both 10 years old) remember believing they were one person, named "Bendanno," when they were younger--although that hasn't stopped the two boys from fighting like cats and dogs.
Inseparable, Ruth and Rachel Sandweiss have lived together for most of their lives. Rachels' recent engagement, though, has created a difficult moment in their relationship. Now, the two women wonder what life will be like no longer being able to spend all of their time together.
Ahna and Irene Fertik, who chose to spend 20 years of their adult lives completely separated from each other (living on opposite coasts of the US). They thought that this would be good for their lives, since they wouldn't be there to constantly influence each other's decisions. But, even with all that time apart, the two still haven't found a happy medium in their relationship.
Paul Goldsmith, for several years now, has been estranged from his twin brother, Aaron. When asked, Paul says he feels as though having an identical twin robs one of their identities. Some twins love being twins, and others absolutely hate it. But twins can’t help having close bonds with each other, as well as constant competition. Being twins means that their lives are unavoidably intertwined. Being twins defines not only their relationships, but also their identities.
Fingerprints of Twins
Identical twins have different fingerprints. Why?
Researchers have found that while identical twins have a very high correlation of loops, whorls and ridges in their fingerprints, that nevertheless in “the detailed ‘minutiae’ — where skin ridges meet, end or bifurcate — there are differences even between identical twins.” Even twins that develop from one zygote occupy different positions in the womb, and this apparently results in variations which are enough to make a difference in the identical twins’ fingerprints.
Conclusion
Perhaps the truth is that all of us, and I mean ALL OF US, really are identical twins.
What happens is that at conception there are always at least 2 fetuses that start out in Mom's womb. For most cases, however, similar to the case of chicks in a bird's nest, one of the fetuses starts to garner more and more of Mom's bounty, and in most cases the 2nd and additional twins wither and die. This is known as the "runting effect" -- the tendency of one identical twin to suck up womb nutrition to the detriment of the other.
Documented cases of this are seen in bird's nest, even to the extreme event where the dominant chick will peck its competing sibling chicks to death or push them out of the nest altogether to die.
According to this view, we really all of us start of as twins, but only a small fraction of us are delivered from mom’s womb, at birth, as twins. The rest of us who are born as single births emerge from the womb alive, having, yes, caused the death of our twin by our very presence and will to live. We have within us the knowledge that we had a twin, and that he or she is not alive, and that we may be responsible for the death.
It has often happened among twins that when one twin dies, the surviving one is inordinately affected, mourns terribly, and in many cases also dies not long thereafter.
Something of the knowledge of our twin persists in all of us who are single births. We know in our heart of hearts that we really had a twin once, and we cannot forget him or her, and we mourn for our lost twin. When we are feeling sad and depressed, we feel this most strongly.
We long for , we yearn for our lost twin. And that is why we seek a mate to marry. We are looking for our twin in our spouse. Sometimes this works, and sometimes it doesn't. But we are searching for our lost twin, who we sometimes also call our "Doppleganger", a German word signifying "double companion", soul mate.
What does all this lead to. Well, people, it is all about the twins, and the shared genes. So if or when anyone has the opportunity to meet or get to know, a person with whom they closely share a gene pool, a father, a mother, a sister, a brother, then is it any wonder that we will go to the ends of the earth to meet them. And so we should. We are naturally attracted to our gene moms, dads, sister, brother, and we love them innately.
