Dysgenics is the decrease in prevalence of traits deemed to be either socially desirable or well adapted to their environment due to selective pressure disfavoring the reproduction of those traits.[1]
The adjective "dysgenic" is the antonym of "eugenic". In 1915 the term was used by David Starr Jordan to describe the supposed deleterious effects of modern warfare on group-level genetic fitness because of its tendency to kill physically healthy men while preserving the disabled at home.[2][3] Similar concerns had been raised by early eugenicists and social Darwinists during the 19th century, and continued to play a role in scientific and public policy debates throughout the 20th century.[4] More recent concerns about supposed dysgenic effects in human populations have been advanced by the controversial psychologist Richard Lynn, notably in his 1996 book Dysgenics: Genetic Deterioration in Modern Populations, which argued that a reduction in selection pressures and decreased infant mortality since the Industrial Revolution have resulted in an increased propagation of deleterious traits and genetic disorders.[5][6]
Despite these concerns, genetic studies have shown no evidence for dysgenic effects in human populations.[5][7][8][9]
^Jordan, David Starr (2003). War and the Breed: The Relation of War to the Downfall of Nations (Reprint ed.). Honolulu: University Press of the Pacific. ISBN978-1-4102-0900-9.
^Carlson, Elof Axel (2001). The Unfit: A History of a Bad Idea. Cold Spring Harbor Laboratory Press. pp. 189–193. ISBN9780879695873.
^Carlson, Elof Axel (2001). The Unfit: A History of a Bad Idea. Cold Spring Harbor Laboratory Press. ISBN9780879695873.
^Neisser, Ulric (1998). The Rising Curve: Long-Term Gains in IQ and Related Measures. American Psychological Association. pp. xiii–xiv. ISBN978-1557985033. There is no convincing evidence that any dysgenic trend exists. . . . It turns out, counterintuitively, that differential birth rates (for groups scoring high and low on a trait) do not necessarily produces changes in the population mean.