Can genes explain our passions and prejudices, the mates we choose, that mystery we call the self? New research on twins upsets some of our most cherished notions about how we become who we are -- and gives nature and nurture a whole new meaning.
In April of 1997 I went down to West 27th Street in Manhattan to sit in the audience of the Maury Povich show, and meet four sets of identical twins who had been separated at birth and adopted into different families. I wanted to see if the same soul stared out of those matched pairs of eyes, to contemplate the near miracle of DNA -- double helix twisting around itself like twin umbilical-cords ticking out a perfect code for two copies of a human. One pair, a Polish nun and a Michigan housewife, had been filmed at the airport by CNN the week before, reunited for the first time in 51 years and weeping in each other's arms, marveling at their instinctive rapport. Yet how alike were they really, if one spent her days on rescue missions to places like Rwanda, while the other cleaned houses to supplement her husband's income?
Twins are nature's handmade clones, doppelgangers moving in synchrony through circumstances that are often eerily similar, as if they were unwitting dancers choreographed by genes or fate or God, thinking each other's thoughts, wearing each other's clothes, exhibiting the same quirks and odd habits. They leave us to wonder about our own uniqueness and loneliness, and whether it's possible to inhabit another person's being. Twins provoke questions about the moment our passions first ignite -- for they have been seen on sonogram in the womb, kissing, punching, stroking each other. They are living fault lines in the ever shifting geography of the nature/nurture debate, and their peculiar puzzle ultimately impacts politics, crime and its punishment, education, and social policy. It isn't such a short leap from studies of behavioral genetics to books like the infamous The Bell Curve (by Richard Herrnstein and Charles Murray) and a kind of sotto-voce eugenics. And so everything from homosexuality to IQ, religious affiliation, alcoholism, temperament, mania, depression, height, weight, mortality, and schizophrenia has been studied in identical and fraternal twins and their relatives.
Yet the answers -- which these days seem to confirm biology's power -- raise unsettling questions. Twin research is flawed, provocative, and fascinating, and it topples some of our most cherished notions -- the legacies of Freud and Skinner included -- such as our beliefs that parenting style makes an irrevocable difference, that we can mold our children, that we are free agents piecing together our destinies.
Today, we've gone twin-mad. Ninety thousand people gather yearly at the International Twins Day Festival in Twinsburg, Ohio. We're facing a near epidemic of twins. One in 50 babies born this year will have a fraternal or identical double; the number of such births rose 33 percent in 1994 alone, peaking at over 97,000 -- largely due to women delaying childbirth (which skews the odds in favor of twins) and to the fertility industry, which relies on drugs that superovulate would-be mothers. Recently, a stunning scientific feat enabled an ordinary sheep to give up a few cells and produce a delayed identical twin a -- clone named Dolly, who was born with her donor's 6-year-old nucleus in every cell of her body. The international furor this Scottish lamb engendered has at its heart some of the same wonder and fear that every twin birth evokes. Twins are a break, a rift in the customary order, and they call into question our own sense of self. Just how special and unique are we?
The history of twins is rich with stories that seem to reveal them as two halves of the same self -- twins adopted into different families falling down stairs at the same age, marrying and miscarrying in the same year, identical twins inventing secret languages, "telepathic" twins seemingly connected across thousands of miles, "evil" twins committing arson or murder together, conjoined twins sharing a single body, so that when one coughs the other reflexively raises a hand to cover the first one's mouth. And yet the lives of twins are full of just as many instances of discordance, differences, disaffection. Consider the 22-year-old Korean twins, Sunny and Jeen Young Han of San Diego County; Jeen hired two teenagers to murder her sister, hoping to assume her identity.
So what is truly other, what is self? As the living embodiment of that question, twins are not just the mirrors of each other, they are a mirror for us all.
Separated at Birth But Joined at the Hip
The woman seated alone onstage at the opening of the Maury Povich show was already famous in the twin literature: Barbara Herbert, a plump 58-year-old with a broad, pretty face and short, silver hair, found her lost twin, Daphne Goodship, 18 years ago. Both had been adopted as babies into separate British families after their Finnish single mother killed herself.
Tags:
biology,
clones,
dna double helix,
fault lines,
gene,
housewife,
maury povich,
maury povich show,
nature,
nature nurture debate,
nurture,
odd habits,
passions,
perfect code,
prejudices,
rescue missions,
sonogram,
synchrony,
twin,
umbilical cords,
womb
