Eugenicists studied twins to explore genetic and environmental influences on human behavior. Twins, some raised separate from one another, were tested intellectually and measured physically. Eugenicists were looking to prove that heredity determines everything about an individual. They examined fingerprints, hair and eye color, temperament, memory, measured every body part, and even asked subjects how they liked their eggs and steak prepared.

twinsThe Archive includes several images from twin studies performed by Otmar Freiherr von Verschuer at the Institute of Hereditary Biology and Race Biology at the University of Frankfurt. These studies were horrifically taken to an extreme by the Nazis in Auschwitz.

On a lighter note, I have been performing my own twin study for almost 13 years now in my own household, and I am often surprised by their similarities as well as their differences. One is fiercely competitive, the other easy going, one muscularly built, the other slender, one loves sour flavors, the other sweets, both love music and are athletic. Although not identical twins, they still share common genetic material and a common upbringing. I wonder how the eugenicists would have analyzed them; how would they explain their similarities and differences?

Oh, and they like their eggs scrambled, and their steak medium.

More on eugenics and twins in the Eugenics Archive: click on Topics, then choose Twin Studies, or just search for twins once you are in the archive.