The author of four books on separated-at-birth and other twins, Segal is in demand as a TV, radio, and courtroom expert. Her studies explore the role of genetics in influencing our fates and shed light on what makes people get along. She was inspired to do this research because she is a twin.
“Twin research is really, really hot. I went to the International Network of Twin Registries in Osaka, Japan, in September. People from all around the world talk about their ongoing work and how collaboration is so vital, because you want to be able to see if findings from one culture replicate in another culture and to what extent they’re different and why that is.”
Her work with twins who were raised in different countries took off with the advent of the Internet because it’s easier for separated pairs to find each other. One pair she studied was born in South Korea and adopted by families in the U.S. and France. Each woman had no idea she had a twin until one posted a video on YouTube and friends of the other saw it. What fascinates Segal about twin reunions is how quickly the siblings “mesh in remarkable ways.”
“That gives us information about the basis of human relationships. It tells you that time together is not requisite to a close relationship. But what is? I think it’s the perception of similarities. If you think about when you’re all by yourself in a foreign country and you find somebody who is from your hometown, you feel a kinship with them.”
Segal started as a researcher in the 1980s with the Minnesota Study of Twins Reared Apart. That landmark probe was launched by the “Jim twins,” identical boys who were raised in separate families. Reunited at age 39, they discovered remarkable similarities: Both smoked Salem cigarettes, drank Miller Lite beer, vacationed on the same beach in Florida, and had worked as part-time sheriffs. “I think they’re very important because it attracted a lot of other pairs to the study.”
Segal is writing a book about two pairs of identical twins in Bogota, Colombia, who were mixed up at the hospital and raised as two sets of fraternal twins. Segal says such a circumstance is extremely rare, and the boys were raised in strikingly different environments. Taking a close look at individual cases is the most exciting aspect of her studies.
“There are many types of twin researchers. Some get big databases and manipulate data on computers. And that’s all fine. But I think what they miss is the thrill of seeing the data come alive, and that’s what I do. I love seeing it come alive. It excites you and gives credence to the quantitative findings. It gives you new ideas, new insights. Every pair is a special take on human development.”