Bell was connected with the eugenics movement in the United States. In his lecture Memoir upon the formation of a deaf variety of the human race presented to the National Academy of Sciences on November 13, 1883 he noted that congenitally deaf parents were more likely to produce deaf children and tentatively suggested that couples where both parties were deaf should not marry. However, it was his hobby of livestock breeding which led to his appointment to biologist David Starr Jordan's Committee on Eugenics, under the auspices of the American Breeders' Association. The committee unequivocally extended the principle to man. From 1912 until 1918 he was the chairman of the board of scientific advisers to the Eugenics Record Office associated with Cold Spring Harbor Laboratory in New York, and regularly attended meetings. In 1921, he was the honorary president of the Second International Congress of Eugenics held under the auspices of the American Museum of Natural History in New York. Organisations such as these advocated passing laws (with success in some states) that established the compulsory sterilization of people deemed to be, as Bell called them, a "defective variety of the human race." By the late 1930s, about half the states in the U.S. had eugenics laws, and California's compulsory sterilization law was used as a model for that of Nazi Germany.
What did Bell like to do that led to his involvement with eugenics?
livestock breeding