When the same unusual print is found on the same finger of both twins, it points toward their being identical. The identical twins born in Bogotá had the same unusual pattern on their left index fingers, a tented arch, an image that appears to have a tent pole rising in the middle. This print is found on fewer than 5 percent of human fingers and thumbs, and the twins were delighted to be part of this select group.20
Twin Type Revisited
My late colleague Dr. David T. Lykken developed a tidy formula for predicting twin type that combined twins’ resemblance across eighteen blood groups, fingerprint ridge count, and two measures of body size, the cephalic index (head width × 100 divided by head length) and the ponderal index (height divided by the cubed root of weight). Using these numbers, the probability of misdiagnosing a pair of twins is less than 0.1 percent.21 Just for fun, we tried this with the Colombian brothers, pairing them every which way, first using their ridge counts alone, then adding their first set of body size measures. The two pairs’ chances of being identical went up as we added information, with the highest probabilities going to the real twins—Jorge and William scored more than 87 percent, and Carlos and Wilber scored more than 89 percent.
Also, just for fun, we reran the calculations using the twins’ second set of body weights. This time the chance that Jorge and William could be identical twins fell to 47.7 percent. William had gained more than twenty pounds, nearly tripling the weight difference between him and his twin from the year before. Of course, the DNA findings are more accurate than the physical measures, showing that they are identical twins with virtually 100 percent certainty.
Epigenetics: City and Country
Numerous studies have compared the epigenetic profiles, or patterns of gene expression, in identical twins, looking for clues to why some pairs differ in complex traits and diseases like smoking or depression, but our study was the first to do this using identical twins and siblings raised apart.22 It turned out that the twins in one identical pair were similar to each other even though they had been raised apart, and Diana was similar to her biological brother William, whom she had never known. However, one of the city-raised twins differed greatly from his country-raised twin, perhaps because he was affected by an unusual event in the womb, but there was no way to test this. A finding of special interest was that the expression of genes that may have been affected by radiation and pesticides was different for the brothers from the city and the brothers from the country. It is too early to know whether the city-raised pair was more adversely affected than the country-raised pair, or even whether these effects are harmful and, if so, to what degree, but such questions can be explored in the future. For now, simply finding this difference in reared-apart identical twins is important.
General Health
Each reared-apart identical twin was much more like his twin brother healthwise than the accidental brother with whom he was raised. William and Jorge’s three-page medical inventories were nearly blank, showing no allergies, no surgeries, no medications, and no broken bones. Neither twin had ever been a smoker. “Gracias Dios no me duele nada!” (Thank God nothing is wrong!), William said. Aside from the leishmaniasis he had contracted in the army, his only complaint was a small benign mass under his right ear that he would have removed. Jorge had nothing to discuss in regard to his health history.
The other identical pair, Carlos and Wilber, had many affirmative answers on their medical forms, perhaps linked to the risks posed by their early birth at twenty-eight weeks to a relatively older mother, such as their low birth weight and her hemorrhaging.23 Both reared-apart twins were self-described crybabies from the start, and their discomforts continued. As young boys each twin had had difficulties pronouncing r and g, but speech therapy corrected Carlos’s problem. Wilber, raised in far more modest circumstances, did not receive therapy so his mispronunciations are still evident. Carlos had worn braces on his teeth to correct poor alignment, whereas his brother wears them now as an adult. Carlos also experiences pain in his wrists, ankles, arms, and fingers from playing basketball and has had hives.
Carlos uses eyeglasses to correct for astigmatism and myopia, while his twin claims not to need them. In fact, when Wilber tried on Carlos’s glasses, they made his vision worse. People who were born prematurely often experience vision problems, the result of early stimulation of the immature visual system, insufficient nutrition from losing contact with the placenta, or other birth complications. And infants born at twenty-eight weeks, like Carlos and Wilber, are at greater risk than infants born later for retinopathy of prematurity, a blinding disease and major cause of visual loss. Carlos’s first few days of life were more challenging than Wilber’s, but it is curious that only one of these early born twins was visually impaired. An early study of twin and nontwin children found that twins are more likely to wear eyeglasses and that twins’ visual problems seemed linked to their prematurity. These identical and fraternal pairs did not differ in their need to wear eyeglasses as a result of a nongenetic cause: their early birth. However, twin studies have found genetic influence on other eye problems, such as refractive error or the eye’s improper bending of light resulting in blurriness.24
Wilber produced an extended list of health issues, the first dating to when he fell off a horse as a young child and required two days of hospitalization. He was riding the horse with William when the horse suddenly jumped. William threw himself to the ground and was unhurt, but Wilber clung to William’s waist and hit his head on a rock. This incident changed the shape of a bone in his head. In addition, Wilber has sought treatment over the years for ear problems, respiratory difficulties, and for a pulled muscle in his back.
Both Wilber and Carlos have histories of smoking, consistent with a genetic influence on this habit. Carlos had his first cigarette when he was ten, smoked spontaneously from time to time after that, and now enjoys only an occasional cigarette. Wilber began smoking when he was eighteen and smoked two or three cigarettes a day for two years before quitting completely. As for alcohol, Carlos drinks less now than he did several years ago because he dislikes having a hangover, but he still enjoys his favorite cocktail, a cabeza de jabalí, a combination of vodka, white rum, gin, tequila, triple sec, and orange juice, garnished with a red cherry. All four twins relish a few beers.
Food Fights and Other Culinary Curiosities
Twin “culture” refers to the habits, rituals, likes, and dislikes that uniquely define each identical twin pair. The reared-apart Chinese twins Mia and Alexandra eat several times during the day, growing hungry each time but filling up fast. The reared-apart Scottish twins Caroline and Margaret routinely left one uneaten square of toast on the plate when they were finished with breakfast. And Tony and Roger from upstate New York seemed to eat just one continuous meal a day. These reared-apart identical men took advantage of an all-you-can-eat pizza restaurant by substituting for one another while one hid in the restroom. They kept this prank up until the harried server who delivered each order refused to comply, but laughed heartily when she realized she’d been had by twins. These quirks are seen much less often in fraternal twins, suggesting that genes play a role, although we do not know how they guide people toward these particular behaviors.
Carlos and Wilber like to “out-eat” each other, which is not surprising because they are the bigger twins and rank eating second in importance to women. Food consumption contests are a large part of Wilber and Carlos’s unique culture, evidenced by an eating contest several months after they met that Carlos won by polishing off his portion and some of Wilber’s. Neither twin could or would engage his respective accidental brother in such activities because each would find these contests unappealing.
Carlos, in particular, defends his individuality, and food is one way he does this. At Bogotá’s trendy Local Gastronomia Nacional, a server handed out lunch menus, but chalkboards posted on the walls listed the specials. Carlos and Wilber studied these offerings and decided on the same meal, shrimp with rice
. “We will have…,” Carlos said, then suddenly grew indecisive before telling the server they would both be having rice, but with different main courses.
Jorge and William are foreigners in their brother’s kitchens and never stage food-eating contests or compete in any apparent way. They do not always order the same dish, although William can be persuaded to have a glass of wine when Jorge does. But they eat off of each other’s plate and sample each other’s meal with the same fork, all done naturally and effortlessly. This level of intimacy is usually displayed by significant others, close relatives, lifelong friends, and twins who have grown up together, so it is striking to witness this interaction between twins who have not been together for long.
* * *
Life events can significantly affect how we eat, with some people turning to food for comfort and others refusing to eat at all. All four brothers had gone through a major upheaval in their lives that may have affected their eating habits. Restrained eaters might refuse to eat for fear of becoming fat, uncontrolled eaters might find it hard to turn down a tempting dish even when they are feeling full, and emotional eaters would consume extra portions and snack when they were feeling anxious. Researchers have found both genetic and environmental influences for these three measures, but a study of the eating habits of Spanish university students may be especially revealing.25
William expressed the highest level of uncontrolled eating, not just among his three brothers, but also higher than these university students. Furthermore, all four brothers outdid the students when it came to emotional eating, possibly reflecting the upheaval in their lives. Of course, we don’t know the brothers’ eating habits before the switch was discovered, so it is impossible to say whether that ordeal explains William’s lack of control or everyone’s emotional eating. We do know that William, one of the switched twins, did not eat well during the first few days after the revelation despite his godmother’s tempting him with his favorite dishes, so his emotional and uncontrolled eating could have reflected his emotional state, even though six months had passed since his history was known.
Scribbles and Scrawls
When Wilber puts pen to paper, he rotates the page counterclockwise until he achieves a perfectly horizontal, or landscape, view, but none of the other three twins does this. I wondered whether this habit might affect his handwriting but, more generally, whether handwriting features were more similar between the related than the unrelated brothers. Of course, both pairs of accidental brothers had learned to write in the same school system, which may have increased their resemblance.
Little recent research has looked at twins’ handwriting similarities, although early twin studies found that identical twins were more alike than fraternal twins in the general quality and speed of their penmanship. But identical twins were not more alike than fraternal twins in individuality or general style of their penmanship, suggesting that genetic factors influence the “coarser outlines of behavior,” whereas the “finer details” are more susceptible to environmental influences and chance.26
Eileen Page is a certified graphologist with years of experience in handwriting analysis. At her suggestion the twins and four of their siblings wrote several sentences about the significance of family, a topic that has the same meaning for all of them.
In fourteen handwriting categories, such as the space between words and the direction of the slant, the three most-similar pairs were biological siblings, even some who had grown up apart, and the four least-similar pairs were biologically unrelated, even those who had grown up together. Most remarkable, the two separated identical pairs were in the top third when it came to similarity. Thus, this modest exercise suggests that genetics may influence some handwriting features to some degree, although graphologists would need to examine handwriting samples from many more twins and their siblings. Curiously, Wilber was the only one who applied heavy pressure to the page.
Becoming Men
In some areas of Colombia, even large cities, fathers or older brothers arrange for their sons or siblings to lose their virginity when they are as young as fourteen. I asked our interpreter, Alberto, about this and he said it was true, then shared a story about a “devirginizing” that he had witnessed in his younger years. A friend’s father had invited the schoolmates of his son Fernando to be at a brothel when he lost his virginity. The boy was about seventeen at the time and certainly no virgin. But Fernando played stupid to make his dad proud, and everyone had a good time on the father’s dime, enjoying a bottle of scotch whiskey to commemorate the occasion. A French schoolgirl “who was neither French nor quite a schoolgirl” came around, but she was a great actress and feigned a heavy Parisian accent. Fernando had a good time drinking, groping the woman, and playing innocent. Alberto wasn’t sure, but he thought Fernando got a “jumbo-deluxe-combo” that night.
A variety of factors, including one’s genes and the environment in which one is raised, influence age at first intercourse. Just how much genes play a role is not clear, with estimates ranging from 0 to 72 percent. Genetic influence seems to be greater among younger people, because many societies have relaxed their sexual restrictions.27
All four Colombian twins were relatively young when they had their first sexual experience. Three twins were fourteen and one twin was seventeen. Their ages are consistent with the 10 percent of Colombian adolescents from Bucaramanga, the capital city of Santander, who have had sexual experiences. The same percentage holds true for teens from Santa Marta, located 450 miles north of Bogotá.28 The Colombian twins’ sexual histories do not allow general conclusions about how much genetic and environmental factors affect age at first intercourse, but twin studies support contributions from both.
Chapter 8
Another World
La Paz and Beyond
Carlos, the switched city-raised twin, called La Paz “nothing and nothing and nothing,” but not in a negative sense. He meant that the small town was simply far from the center of things, “another reality.” This may explain why William, the switched country-raised twin, insisted that we see the home and town where he grew up.
They lived somewhere between the tiny towns of Vereda El Recreo and Vereda Colon, another world in our eyes. No one had computers, and the town had no paved roads or grocery stores. The twins’ house had no running water, or any plumbing at all, and stood surrounded by trees, plants, and other wildlife. The house now belonged to Chelmo, one of the older La Paz brothers, because their parents had moved a three-hour walk away to La Guayabita, an area closer to stores and neighbors. The journey to Chelmo’s farm is one that people in the area make without hesitation because they know no other options. Even small children scoot up the uneven hills and wade through muddy puddles without fear of falling. Crowded buses and fast cars disturb people from La Paz when they venture into Bogotá or the nearest big city, Bucaramanga, while city kids in Bogotá clamor to sit in the front seat to watch their world pass by. And city kids, used to buses, cars, and taxis, complain about having to walk more than half a mile.
Despite its isolation the areas around La Paz have a rich and complex culture. Residents celebrate the annual Festival for the Virgen del Carmen, the patron saint of all vehicles, curious because most people in the surrounding areas do not have cars since there are no roads, although some drive motorbikes. They also hold various religious services and political demonstrations for peace, but the festivals and other events are hours away and happen only occasionally.
Getting There
Traveling from Bogotá to the twins’ childhood home in La Paz is challenging. Under normal conditions it means a five-hour ride by highway to Vélez, followed by a one-hour drive to La Paz through rough woods and over large rocks and muddy streams in a four-wheel-drive vehicle, then a one-hour hike through the same treacherous terrain to the house. Horseback is an option for the final leg of the trip, but most people who live there just walk. Residents say the walk takes fifteen to thirty minutes, but while we walked, they kept great
ly underestimating the time remaining, perhaps to reassure first-time visitors to the area like us. This is understandable because the people in La Paz are used to getting around on foot. In contrast, city folk tend to overestimate distances and arrival times, probably because they include walking speed and traffic in their calculations.1
Being There
We were headed to a barbeque at William and Wilber’s childhood home hosted by their parents, Ana Delina and Carmelo. The four twins had different feelings about this Sunday afternoon affair. The biological brothers Jorge and William, ever the extroverts and social butterflies, anticipated it eagerly, seeing it as an opportunity to bask in the attention of the one hundred or so friends and family members whom William had insisted on inviting. Among them would be the La Paz brothers’ former teacher, who had made the one-hour walk to school with them each day; their friend Edgar Pardo, who owned the Bogotá butcher shop where they worked; and the town’s former mayor, Ermes Amado, who had political connections that appealed to William. The more private, pragmatic, and self-described mature identical twin pair, Carlos and Wilber, disliked the attention-seeking tendencies of the other two, believing that the switch and its aftermath were serious life-changing events, not the stuff of show business or political ambitions. They grudgingly allowed themselves to be dragged along, but worried that the crowd of guests would turn the four twins into local entertainment. That each twin would have the same reaction as his recently reunited double is not surprising, because genes have a significant influence on how we process information.2
Many people around La Paz would have been unaware of the twins’ story on Séptimo Día because they didn’t have TVs, but news of the switch had spread quickly among area residents by cell phone or during visits. Everyone was excited to see the mirror images of the two boys they had known since childhood and felt honored to be visited by university faculty from the United States. In this respect the people of La Paz and Bogotá were no different, obsessed as they were with the twins’ story and eager for more details. After the first televised segment aired, Séptimo Día had received a flood of calls from doctors, psychologists, sociologists, and general viewers, literally forcing the station to produce a follow-up.
Accidental Brothers Page 20