Twins as a window into nature and nurture | Hidden Brain In December 1988, two pairs of twin boys were born in Colombia. One twin from each pair was accidentally given to the wrong mother — a mistake that wasn't discovered for decades. The twins' story is a tragedy, a soap opera, and a science experiment, all rolled into one. It also gives us clues about the role that genes and the environment play in shaping our identities. We talk with psychologist Nancy Segal about her work with twins, and her encounters with these now-famous brothers. For research related to this episode, please visit https://n.pr/2uvpvPe
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What Twins Can Tell Us About Who We Are

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What Twins Can Tell Us About Who We Are

What Twins Can Tell Us About Who We Are

What Twins Can Tell Us About Who We Are

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  • Transcript

In March of 2017, the two sets of Bogotá twins, Jorge, William, Carlos and Wilber (left to right), gathered to celebrate Carlos's graduation. Diana Carolina/St. Martin's Press hide caption

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Diana Carolina/St. Martin's Press

In March of 2017, the two sets of Bogotá twins, Jorge, William, Carlos and Wilber (left to right), gathered to celebrate Carlos's graduation.

Diana Carolina/St. Martin's Press

In December 1988, two sets of identical twins in Bogotá became test subjects in a study for which they had never volunteered. It was an experiment that could never be performed in a lab, and had never before been documented. And it became a testament to the eternal tug between nature and nurture in shaping who we are.

The brothers as children. From left to right: Carlos and Jorge at age 5, and Wilber and William at age 6. Courtesy of Jorge and Carlos; William and Wilber/St. Martin's Press hide caption

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Courtesy of Jorge and Carlos; William and Wilber/St. Martin's Press

The brothers as children. From left to right: Carlos and Jorge at age 5, and Wilber and William at age 6.

Courtesy of Jorge and Carlos; William and Wilber/St. Martin's Press

This week, psychologist Nancy Segal tells the story of the Bogotá twins, which was a tragedy, a soap opera, and a science experiment, all rolled into one. And she explains why twin studies aren't just for twins. They can serve as a paradigm to understand age-old questions that affect us all: Is our fate written in our genes? And how powerful is upbringing in shaping who we become?

Insights — and provocations — from twin studies, this week on Hidden Brain.

Additional Resources:

"Accidental Brothers: The Story of Twins Exchanged at Birth and the Power of Nature and Nurture," by Nancy Segal and Yesika Montoya, 2018

"Born Together—Reared Apart: The Landmark Minnesota Twin Study," by Nancy Segal, 2012

"Pairs of Genetically Unrelated Look-Alikes: Further Tests of Personality Similarity and Social Affiliation," by Nancy Segal and colleagues, 2018

"Socioeconomic Status Modifies Heritability of IQ in Young Children," by Eric Turkheimer and colleagues, 2003

"Personality Similarity in Twins Reared Apart and Together," by Thomas Bouchard and colleagues, 1988

Hidden Brain is hosted by Shankar Vedantam and produced by Jennifer Schmidt, Parth Shah, Rhaina Cohen, Laura Kwerel, and Thomas Lu. Our supervising producer is Tara Boyle. You can also follow us on Twitter @hiddenbrain, and listen for Hidden Brain stories each week on your local public radio station.