A leading expert on twins delves into the stories behind her research to reveal the profound joys and real-life traumas of twelve remarkable sets of twins, triplets, and quadruplets.

Indivisible by Two introduces us to an assortment of memorable characters, from the "Fireman Twins"--brothers who, though reared separately, are astonishingly similar in personality and behavioral traits--to the twin sisters who overcame one twin's infertility by having the other serve as her surrogate mother. We meet one of the few identical brother-sister pairs in the world after one of two...

The identical "Jim twins" were raised in separate families and met for the first time at age thirty-nine, only to discover that they both suffered tension headaches, bit their fingernails, smoked Salems, enjoyed woodworking, and vacationed on the same Florida beach. This example of the potential power of genetics captured widespread media attention in 1979 and inspired the Minnesota Study of Twins Reared Apart. This landmark investigation into the nature-nurture debate shook the scientific community by demonstrating, across a number of traits, that twins reared separately are as alike as...