The 1930s image on the cover of American Genes* is an abstract tree, a common eugenics symbol. There were several interpretations or uses of the tree.

• One was to show how a healthy tree, representing a healthy society, could be damaged by a harmful vine choking off its growth. The two hands cutting away the deadly vine is eugenics at work. In the 1930s and today, the eugenics goal is to limit genetically inferior people from having children, who will be dependent on society for care.
• The second interpretation is a family tree, which shows how one person with defective genes could produce dozens of offspring who were also flawed. The most infamous of these interpretations was Goddard’s book about the Kallikak family.
• Finally, trees appeared in various other forms in eugenic posters, newspapers, and books during the height of the eugenics era. The tree analogy was common in both American and Nazi propaganda.

* Cover image licensed by Wikimedia Commons.

Here are some of websites and documents for those who want to dig deeper into eugenics.

Involuntary sterilization in America
Eugenics Information and Perspectives
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