Separated and switched-at-birth twins reveal traits that may further the nature versus nurture debate

Making the news recently has been several cases of children switched at birth—that is, the child is sent home to the wrong parents. Years later the switch is discovered, but by this time, each child has been raised in someone else’s family. It is estimated that about 20,000 accidental baby switches occur annually, although most are quickly detected. But what happens if the switch happens to twins and they are switched for decades?

Nancy Segal, in her research, Someone Else’s Twin, documents cases of separated twins. Segal presents three documented suppositions:

(1) Genetics is dominant (i.e. nature is more dominant than nurture) – Intelligence and personality are generally genetic; Segal noted that these traits were constant in identical twins raised apart. However, job satisfaction, materialism, and attachment styles are more heavily shaped by home life, i.e. nurture (the way a child is raised).

(2) Parents bond to the child they raise – Even though parents had concerns that their switched child did not look like them, they never doubted that the child was their own. When the switch was discovered, they found it difficult to part with the twin they raised, and to bond with a new child (despite it being their true child).

(3) Similarities lead to friendships – the identical separated twins in Segal’s studies reported an instant connection when they met for the first time, often decades later. They immediately felt like old friends.