Dysgenics

In population genetics, dysgenic is a term describing the progressive evolutionary "weakening" of a population of organisms relative to their environment, often due to relaxation of natural selection or the occurrence of negative selection. The antonym of dysgenic is eugenic (see also Eugenics).

The plural noun dysgenics refers to "racial degeneration" or "genetic deterioration", the opposite of eugenics, first so used by Aldous Huxley in 1920. An example of "dysgenics" in human populations is the controversial claim of Richard Lynn that IQ and other socially valued traits are deteriorating due to fertility differences between social groups.

History of the term
The term first came into use as an opposite of eugenics, a social philosophy advocating improvement of human hereditary qualities, often by social programs or government intervention.

According to the Oxford English Dictionary, the term "dysgenic" was first used as an adjective as early as 1915 by David Starr Jordan to describe the "dysgenic effect" of World War I. He believed that fit men were as likely to die from modern warfare as anyone else, and war was seen as killing off only the physically fit male members of the population whilst the disabled stayed safely at home.

In the 1930s, Julian Huxley, who later became the first director of UNESCO, was concerned by dysgenics and described eugenics as "of all outlets for altruism, that which is most comprehensive, and of longest range".

In 1963, Weyl and Possony asserted that comparatively small differences in average intelligence can become very large differences in the very high I.Q. ranges. A decline in average psychometric intelligence of only a few points will mean a much smaller population of gifted individuals.

Colum Gillfallen in 1965 argued that lead used by Romans in plumbing and cooking utensils poisoned the water and food of the Roman elite. He concluded, "It follows ... that whatever qualities enabled Roman individuals to make money, or to marry or mate with money, were rigorously bred out of the race and culture by lead and other forces" and caused the decline of the Roman Empire. In 1985, the Gillfallen paper was refuted by Needleman and Needleman. They found that "the lead employed in the main water-supply system was almost certainly harmless". Calcium deposits from hard water prevented contact with the lead. Where the water was soft (rare in the most populated areas), continuous flow of water caused dissolved lead concentration to be small. They agree that lead poisoning from cooking utensils was potentially hazardous. However, measurements of lead from bones of Romans and other peoples provide no evidence that the fertility of the Roman elite was adversely affected.

William Shockley (a Nobel laureate in Physics) used the term in his controversial advocacy of eugenics from the mid 1960s through the 1980s; he and his theories were unfavorably portrayed in the press. Shockley argued that "the future of the population was threatened because people with low IQs had more children than those with high IQs," and his theories "became increasingly controversial and race-based".

Robert K. Graham in 1998 argued that genocide and class warfare, in cases ranging from the French Revolution to the present, have had a dysgenic effect through the killing of the more intelligent by the less intelligent, and "might well incline humanity toward a more primitive, more brutish level of evolutionary achievement."

Dysgenics and IQ testing

 * See also: Inheritance of intelligence

Most of the scientific focus on dysgenics in human populations in recent years has investigated the change in genotypic intelligence. Demographic studies generally indicate that the more intelligent and better educated women in affluent nations have much lower reproductive rates than the less educated, which has led to concern regarding the future of intelligence in these nations. The most cited work is Vining's 1982 study on the fertility of 2,539 U.S. women aged 25 to 34; the average fertility is correlated at -0.86 with IQ for white women and -0.96 for black women, which indicates a drop in the genotypic average IQ of 1.6 points per generation for the white population and 2.4 points per generation for the black population.

A 2004 study by Richard Lynn and Marian Van Court returned similar results, with the genotypic decline measuring at 0.9 IQ points per generation for the total sample and 0.75 IQ points for whites only. Richard Lynn has been criticized for distorting and misrepresenting data by some scholars. However, Lynn's work on dysgenics has been reviewed neutrally or favorably in some journals.

Bioethical debate
Some parents might choose to use reproductive technologies to select genetic traits which are commonly regarded as diseases or handicaps by the majority of the social matrix. For example, some deaf parents might want to use reproductive technology to guarantee that their children would be deaf. Some authors have argued that their wish to have disabled children should not be condemned but Rui Nunes points out that this practice could be regarded as unethical "because the basic human right to open future is violated".

In fiction

 * Cyril M. Kornbluth's short story "The Marching Morons" is an example of dysgenic fiction.
 * Mike Judge's film Idiocracy is a comedy about a future where dysgenics has caused everyone to be stupid.
 * T. J. Bass's novels Half Past Human and The Godwhale describe humanity becoming cooperative and "low-maintenance" to the detriment of all other traits.
 * H. G. Wells' 1895 novel, The Time Machine, describes a future world where humanity has degenerated into two distinct branches who have their roots in the class distinctions of Wells' day. Both have sub-human intelligence and other putative dysgenic traits.
 * The 2007 song "Evolution" by Korn warns against dysgenics.

General

 * Galor, Oded and Omer Moav: Natural selection and the origin of economic growth. Quarterly Review of Economics 117 (2002) 1133-1191.
 * Hamilton, W. D. (2000) A review of Dysgenics: Genetic Deterioration in Modern Populations. Annals of Human Genetics 64 (4), 363-374. doi: 10.1046/ j.1469-1809.2000.6440363.x
 * Shockley on Eugenics and Race: The Application of Science to the Solution of Human Problems Scott-Townsend, 1992
 * Thomas W. Teasdale and David R. Owen (2005). "A long-term rise and recent decline in intelligence test performance: The Flynn Effect in reverse." Personality and Individual Differences 39(4), pp 837–843.
 * Vining, D.R., 1982. On the possibility of a re-emergence of a dysgenic trend with respect to intelligence in American fertility differentials. Intelligence 6, pp. 241—264.

External references
Future Generations, Personal eugenics website of Marian Van Court

Dysgenik Dysgenetica