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Nancy Segal — Twins, Behavior Genetics, Eugenics, and Human Behavior

Gay Fathers, Twin Sons: The Citizenship Case That Captured the World (book cover)

This episode is a conversation based Nancy Segal’s two new books The Twin Children of the Holocaust: Stolen Childhood and the Will to Survive and Gay Fathers, Twin Sons: the Citzenship Case that Captured the World.

Shermer and Segal discuss:

  • her historical interest in twins research and behavior genetics
  • the many different types of twins and family arrangements
  • twins separated accidentally (switched with an unrelated infant, switched with another twin)
  • twins separated intentionally
  • twins reunited
  • a brief history of twins research
  • Josef Mengele and his twins research
  • Minnesota Study of Twins Reared Apart
  • the gay fathers and twin sons story
  • immigration and naturalization law related to IVF, twins, gay couples, etc.
  • abortion
  • eugenics and the Nobel Prize sperm bank
  • the meaning of “heritability”
  • the relative role of nature and nurture in how lives turn out, and
  • the “nonshared environment.”

Nancy L. Segal, PhD, is a Psychology Professor, and Director and Founder of the Twin Studies Center at California State University, Fullerton. She has authored over 300 scholarly articles and eight books. Her 2012 book, Born Together-Reared Apart: The Landmark Minnesota Twin Study, won the American Psychological Association’s William James Book Award. Her recent work, Deliberately Divided: Inside the Controversial Study of Twins and Triplets Adopted Apart, was the focus of a July 2022 BBC-TV documentary. Her work has been featured in the New York Times and Atlantic Monthly. She has appeared on national and international televised programs, including the Oprah Winfrey Show, Good Morning America, the Today Show and the BBC. She is also the author of The Twin Children of the Holocaust: Stolen Childhood and the Will to Survive, an annotated collection of photographs taken at the Holocaust twins’ 40th anniversary reunion and hearing on Josef Mengele’s war crimes. Her other books include Entwined Lives: Twins and What They Tell Us About Human Behavior, Indivisible by Two: Lives of Extraordinary Twins, Someone Else’s Twin: The True Story of Babies Switched at Birth, Twin Mythconceptions: False Beliefs, Fables, and Facts About Twins, and Accidental Brothers: The Story of Twins Exchanged at Birth and the Power of Nature and Nurture. Segal lives and works in southern California.

About the Book

The January 2018 headline story in the Los Angeles Times was riveting. Andrew from the United States and Elad Dvash-Banks from Israel married in Canada in 2010 when gay couples could not marry in these countries. The couple conceived fraternal twins, Aiden and Ethan, with a Canadian surrogate by means of egg and sperm donation. The two boys were born just four minutes apart. Aiden was conceived with a donated egg and Andrew’s sperm cell, and Ethan was conceived with a donated egg (from the same woman) and Elad’s sperm cell.

Andrew and Elad wished to raise their children in the United States, but when they arrived at the American Consulate in Toronto to apply for citizenship, a staff member fired off a series of “shocking” and humiliating questions, and informed the couple of her authority to require a DNA test to determine each parents’ relatedness to each twin—she warned that without these tests neither twin would be granted U.S. citizenship. Andrew and Elad knew which twin each had fathered and had planned on keeping this information confidential. They knew this because DNA analyses had already been performed, but the consulate insisted that these costly tests be repeated using their designated laboratory.

Having no alternative, DNA testing was arranged, and results submitted to the consulate. Soon, two envelopes arrived at their home, bearing both welcome and dreaded news: United States citizenship was offered to Aiden, whose father was a U.S. citizen, but not to Ethan, whose father was Israeli. And, thus, their ground-breaking legal journey began. The couple’s high-profile lawsuit nearly reached the U.S. Supreme Court, capturing worldwide attention along the way.

Nancy Segal brings the story to life through firsthand accounts of each father’s life history and analysis of the legal intricacies that threatened to deny U.S. citizenship to one of their twin sons.

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This episode was released on September 1, 2023.

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