Big news out of Minnesota regarding twins. No, not that sappy, crappy baseball team toiling away in futility at Target Field. It’s a new book on the landmark Minnesota Study of Twins Reared Apart. A review of Born Together—Reared Apart appeared in today’s WSJ:
In early 1979, a pair of identical twin brothers who had been separated at four weeks were reunited after 39 years. Both named Jim, they discovered that they smoked the same brand of cigarettes, vacationed in the same town and both called their dog "Toy." Struck by the story, psychologists at the University of Minnesota started studying separated twins that same year. Their efforts blossomed into the Minnesota Study of Twins Reared Apart, which ran for a quarter century, attracting world-wide fascination and antipathy.
Nancy Segal's "Born Together—Reared Apart" is a thorough history of the project and of the 137 pairs of star-crossed twins who made it possible. Ms. Segal, a key member of the Minnesota team, focuses on the many scientific publications that emerged from the data. But along the way, readers meet leading twin researchers and a whole lot of twins—including the "Jim twins," the "giggle twins" (who both laughed almost nonstop) and, most incredibly, Oskar, raised as a Nazi, and his identical brother, Jack, who was raised as a Jew.
If you harbor any curiosity about why people turn out the way they do, Ms. Segal's topic will fascinate. How big are the effects of nature, nurture and everything else? Despite ample jargon and abstruse statistics, the logic of the Minnesota study is simple. When identical twins are raised apart, you can disentangle nature and nurture for a given characteristic by simply measuring how similar the twins are. You can double-check your answer by comparing the similarity of identical twins (who share all their genes) and of fraternal twins (who share only half their genes).
The results of the study are indeed fascinating and provide fertile ground for those interested in the age old nature vs. nurture debate. Based on what I know of the study, the data leans pretty heavily in favor of the former. While some (especially those of the progressive engineering of society bent) will no doubt find those conclusions disturbing, there’s actually a message that the overly-anxious, overly-involved parents of today should heed: your efforts to raise the perfect child don’t matter nearly as much as you think they do. The bottom line is that your seeds are more important than your deeds. So relax and enjoy the ride.