How Twins Saved Biology from Eugenics.
Eugenics, one of the dark chapters of biology, was one of the first approaches of natural scientists to make their science socially and politically relevant, not knowing they would be actively involved in its own decline. The lack of a correlation between certain traits, like IQ or criminal history, to heredity or race, is what ultimately proved eugenics wrong. From the Eugenics archive of Cold Spring Harbor Laboratory’s, A scientific paper, “Mental and Physical Traits of Identical Twins Reared Apart”, from Horatio Newman in 1928, provides evidence on how science was a crucial factor for the downfall of eugenics. Even though eugenics was the result of attempting to give social application to the latest biological discoveries, it was also science itself what drove the decline of this morally questionable social movement.
Encouraged by the current progressivism in the United States in the change of the XIX to XX century, the newest theories of evolution and heredity inspired eugenics as a way to improve society. Charles Darwin’s cousin, Francis Galton, first conceived eugenics as the idea that intelligence, moral attitudes, criminal history, and other social behaviors were purely inherited traits and that the human population could be improved by selective breeding. Biologists who looked for an actual mechanism of heredity thought to have proven eugenics right. The anti-Lamarck findings of August Weismann showed that the hereditable material came only from germ cells, which were not prone to environmental change during the lifetime of an organism. Such findings “scientifically” reinforced eugenics. Its advocates concluded that it was pointless to educate or aid people with a negative behavioral or intellectual background because their genotype would not be changed. Biologists who agreed with this movement saw the economical and social potential of backing it up. They were not wrong considering all the funding and social recognition that eugenics gained in the course of the next couple of decades.
During the period of apparent success of Eugenics, one of the few research findings produced concerning eugenics, Newman’s twins study, suggested that the radical inheritance ideas of eugenicist were false. Hontario Newman was a professor of zoology at the University of Chicago and a member of the American Eugenics Society, confirmed by being one of the recipients in a letter from the field secretary of such organization (Cold Spring Harbor Laboratory’s Archive). Identical twins were of high interest between eugenicists because the monozygotic origin of this kind of twins could confirm the actual influence of environment versus inheritable traits in the life of a human being. Newman’s scientific article, aimed for fellow eugenicists, describes the mental, physical and social testing and comparison of a pair of identical female twins. The twins were separated after birth and were adopted by families differing greatly in their intellectual and educational environment. This study found that the female reared by an intellectual family that worried about her social and educational environment, scored significantly better on intellectual tests, as well as to be much more socially active. The relevance of this paper lays on the conclusion that intelligence and social attitudes are not purely inheritable traits; rather the environment plays a decisive role on their development. This idea contradicts with the basic principles of eugenics serving as one of the earliest proofs of the inconsistency of this social movement.
Around the time when Newman published his findings, the mid 1920s, biologists started rejecting eugenics and it became obvious that its downfall was not far. According to Philip J. Pauly, in Biologists and the Promise of American Life, around this decade most of the main eugenic supporter biologists abruptly changed their minds on the subject. Pauly mentions Raymond Pearl, Edward M. East, and Herbert S. Jennings as important scientists who abandoned eugenics. Few years latter, in 1934 the Eugenics Record Office was shat down. Even though biologists promoted the beginnings of eugenics, their findings that contradicted eugenic principles and their subsequent retreat from the social movement, clearly added inertia to the ending of one of the darkest chapters of biology.
Bibliography
- Newman, Horatio Hackett. 1928. Mental and Physical Traits of Twins Reared Apart. Journal of Heredity. Vol. (25).
- Pauly, Philip Joseph. 2000. Biologists and the Promise of American Life: From Meriwether Lewis to Alfred Kinsey. Princeton and Oxford: Princeton University Press.