In 2011, Sonja Vernes and Simon Fisher performed a series of experiments to determine which developmental processes are controlled by the mouse protein Foxp2. Previous research showed that altering the Foxp2 protein changed how neurons grew, so Vernes and Fisher hypothesized that Foxp2 would affect gene networks that involved in the development of neurons, or nerve cells. Their results confirmed that Foxp2 affected the development of gene networks involved in the growth of neurons, as well as networks that are involved in cell specialization and cell communication. The researchers determined that Foxp2 is important for a variety of developmental processes such as motor control, language acquisition, and cognition.

Lewis Madison Terman was a researcher and university professor who studied educational psychology and advocated for eugenics in the United States during the early twentieth century. The US eugenics movement, which Terman supported, was a collection of scientific research and social programs that aimed to improve human populations through control over human reproduction. One area many eugenicists studied was human intelligence as a means of determining how “desirable” a person may be. During the 1910s, while working at Stanford University in Palo Alto, California, Terman helped devise the Stanford-Binet scale for intelligence testing. As of 2024, the Stanford-Binet test is one of the main methods for providing individual intelligence quotient, or IQ, scores. In addition to the Stanford-Binet scale, Terman promoted the idea that individuals had fixed and inherited capacities for intelligence. Through both his development of a widely used method for measuring human intelligence and his promotion of the idea of intelligence as hereditary, Terman supported widespread social efforts to control human reproduction in the US during the twentieth century.