MEASURING
TWINS

QUANTIFYING
LIFE

A designated “examination room for twins” used to be in the basement of the building at Ihnestraße 22. The Institute was considered an international leader in the study of twins. Researchers sought to answer the key question: is it genes or environments that determine appearance, behaviour, and diseases in humans?

The researchers understood monozygotic twins to be genetically identical. They therefore attributed differences between them to environmental influences, while similarities were understood to be due to genes. Researchers documented the differences between monozygotic twins numerically and compared them with the differences between dizygotic twins. Their aim was to mathematically determine the heritability of a trait.

Photograph of three individuals in an examination room. One person wearing a dress or a long white lab coat is taking a picture from the side of a person sitting on a chair. The twin sister of the person being photographed is standing to one side.
A pair of twins being photographed at the Institute, around 1930 ullstein bild

At the Institute, sets of twins were examined, measured, and photographed. Photos like this one were meticulously staged. They presented the Institute as a modern institution that conducted research on humans under laboratory conditions.

A photograph of a White man wearing a white lab coat. His name is Otmar von Verschuer. He is standing next to an open drawer of a filing cabinet and reading a document from the file on twins.
Otmar von Verschuer with the “twin files”, date unknown Archive of Max Planck Society, Berlin-Dahlem, Abt. VI., Rep. 1, Verschuer, Otmar von I/7

Otmar von Verschuer showcases the Institute’s “twin files”. At the beginning of the 1930s, medical data was collected on the more than 700 twins examined at the Institute. Large amounts of data were important for the “twin method” because the influences of environment and heredity were to be measured statistically. After 1945, Verschuer continued expanding the files at the University of Münster.

A postcard of the children’s sanatorium “Kaiserin Friedrich Seehospiz,” which consisted of 15 red brick buildings erected near the beach. In the top half of the picture the North Sea is depicted in the background.
Postcard of the children’s sanatorium Seehospiz “Kaiserin Friedrich” on Norderney, date unknown Diakonia and Development Archives, Berlin

On the island of Norderney, off the North Sea coast of Germany, Kurt Gottschaldt, head of the Department of Hereditary Psychology, organised “twin camps” in 1936 and 1937. Other camps took place near Berlin. A total of over 300 children spent their summer holidays there. Researchers wrote “behaviour and mood reports” on each child twice a day. Throughout his life, Gottschaldt worked on collating this disparate data into a clear format.

This is a photograph of a White man sitting at a table. His name is Otmar von Verschuer. He is wearing a white lab coat, and his arms are crossed.
Otmar von Verschuer at his desk, date unknown Archive of Max Planck Society, Berlin-Dahlem, Abt. VI., Rep. 1, Verschuer, Otmar von I/2

Otmar von Verschuer

The young scientist Otmar von Verschuer (1896–1969) was appointed Head of the Department of Human Heredity by Founding Director Eugen Fischer. He established the Institute as a centre for the study of twins. In 1942, Verschuer succeeded Fischer as its director.

Verschuer had close connections to the Auschwitz-Birkenau concentration and extermination camp. In fact, the “camp doctor”, Josef Mengele, had learned the “twin method” from him. Mengele carried out his personal research programme on twins imprisoned in Auschwitz-Birkenau. At the very least, Verschuer simply accepted that Institute staff conducted research on the bodies of those murdered in the camps. After 1945, Verschuer continued his career as a professor at the University of Münster.

The other illustration shows photographs of a pair of twins at the ages of 17, 20, 29, and 43.
From: Otmar von Verschuer, “Relevant Impacts on Human Life”, 1954 University Library of Freie Universität Berlin

After 1945, Verschuer continued the research he had started in the 1920s on a group of twins. He had also conducted examinations of these same twins at the Institute during the National Socialist period, something he avoided mentioning in his book. In the chart above, Verschuer only recorded observations from the years 1927 and 1953.

Black and white photo. View of the main building of the Kaiser Wilhelm Institute for Anthropology, Human Heredity and Eugenics from Ihnestraße.
The main building of the Kaiser Wilhelm Institute for Anthropology, Human Heredity and Eugenics, after 1936 Archive of Max Planck Society, Berlin-Dahlem, Abt. VI. Rep. 1, Nr. KWI-Anthrop I/4b
Photograph of three individuals in an examination room. One person wearing a dress or a long white lab coat is taking a picture from the side of a person sitting on a chair. The twin sister of the person being photographed is standing to one side.
A pair of twins being photographed at the Institute, around 1930 ullstein bild
A photograph of the inner courtyard of Friedrich Wilhelm University in Berlin. There are many people in the courtyard. Eugen Fischer is standing on the balcony, giving a speech. A large banner with a swastika is hanging from the parapet.
Eugen Fischer at a speech at the Friedrich Wilhelm University Berlin, 1933 Süddeutsche Zeitung Photo/Scherl
Black and white photo. View of the main building of the Kaiser Wilhelm Institute for Anthropology, Human Heredity and Eugenics from Ihnestraße around 1933/34, with a swastika flag flying on a flagpole.
The main building of the Kaiser Wilhelm Institute for Anthropology, Human Heredity and Eugenics, around 1933/34 Archive of Max Planck Society, Berlin-Dahlem, Abt. VI. Rep. 1, Nr. KWI-Anthrop I/4a
The second image is a photograph of a woman with dark skin, doctoral candidate Irawati Karvé. She is standing next to a table with a row of skulls.
Irawati Karvé with human skulls in the Institute’s “unpacking room”, date unknown Private Archive of Irawati Karvé/Urmilla Deshpande

AtticDehumanisation