Jump to content

Dysgenics: Difference between revisions

From Wikipedia, the free encyclopedia
Browse history interactively
← Previous editNext edit →
Content deleted Content added
VisualWikitext
m WPCleaner (v1.08) Headline hierarchy (Fixed using WP:WCW)
m wikify several non-external links
Line 8: Line 8:
During 1965, Colum Gillfallen speculated in ''[[The Mankind Quarterly]]'' that [[lead]] used by Romans for [[plumbing]] and [[cooking]] utensils poisoned the water and food of the Roman elite, causing the [[decline of the Roman Empire]].<ref>{{cite journal| author = Gillfallen SC| title = Roman Culture and Dysgenic Lead Poisoning| journal = The Mankind Quarterly| volume = 5| issue = 3| pages = 131–148| date= January–March 1965| id = ISSN 0025-2344}}</ref> Gillfallen's theory was refuted during 1985 by Needleman and Needleman, who showed that measurements of lead from bones of Romans and other peoples did not provide any evidence that the fertility of the Roman elite was adversely affected.<ref name="Needleman">{{cite journal| author = Needleman L, Needleman D| title = Lead Poisoning and the Decline of the Roman Aristocracy| jo urnal = Classical Views| volume = 4| issue = 1| pages = 63–94| year= 1985| id = ISSN 0012-9356}}</ref>
During 1965, Colum Gillfallen speculated in ''[[The Mankind Quarterly]]'' that [[lead]] used by Romans for [[plumbing]] and [[cooking]] utensils poisoned the water and food of the Roman elite, causing the [[decline of the Roman Empire]].<ref>{{cite journal| author = Gillfallen SC| title = Roman Culture and Dysgenic Lead Poisoning| journal = The Mankind Quarterly| volume = 5| issue = 3| pages = 131–148| date= January–March 1965| id = ISSN 0025-2344}}</ref> Gillfallen's theory was refuted during 1985 by Needleman and Needleman, who showed that measurements of lead from bones of Romans and other peoples did not provide any evidence that the fertility of the Roman elite was adversely affected.<ref name="Needleman">{{cite journal| author = Needleman L, Needleman D| title = Lead Poisoning and the Decline of the Roman Aristocracy| jo urnal = Classical Views| volume = 4| issue = 1| pages = 63–94| year= 1985| id = ISSN 0012-9356}}</ref>


The psychologist [http://en.wikipedia.org/wiki/Robert_Hare_(psychologist) Robert Hare] in his book, "Without Conscience: The Disturbing World of Psychopaths among Us",<ref>{{cite book|last=Hare|first=R.|title=Without Conscience|year=1999|publisher=The Guilford Press|isbn=1-57230-451-0|pages=70, 166–177|url=http://www.amazon.com/Without-Conscience-Disturbing-World-Psychopaths/dp/1572304510}}</ref> puts forth the theory that [http://en.wikipedia.org/wiki/Psychopathy psychopathy] has a genetic predispostion. Hare claims are supported in part from brain scans,<ref>{{cite news|last=Sutliff|first=U|title=Out of Order|url=http://www.usc.edu/uscnews/stories/9861.html|newspaper=USC News|date=Feb. 2004}}</ref> and twin studies.<ref>{{cite news|title=The Origins of Antisocial Behaviour, Twin Study|url=http://www.medicalnewstoday.com/releases/25078.php|newspaper=Medical News Today|date=May 2005}}</ref> Psychopaths do indeed show brain anomallies, which if not genetic, the author claims that it would indicate the condition is hard-wired from birth. Hare goes on to state that many psychopaths, a malady that arrises primarily in males, have a pattern of mating with, and quickly abandoning women, and as a result, procures a higher fertility rate. It is stated in the book that many of these spawned children will inherit a predisposition to psychopathy. Hare describes the implications as chilling.
The psychologist [[Robert Hare (psychologist)|Robert Hare]] in his book, "Without Conscience: The Disturbing World of Psychopaths among Us",<ref>{{cite book|last=Hare|first=R.|title=Without Conscience|year=1999|publisher=The Guilford Press|isbn=1-57230-451-0|pages=70, 166–177|url=http://www.amazon.com/Without-Conscience-Disturbing-World-Psychopaths/dp/1572304510}}</ref> puts forth the theory that [[psychopathy]] has a genetic predispostion. Hare claims are supported in part from brain scans,<ref>{{cite news|last=Sutliff|first=U|title=Out of Order|url=http://www.usc.edu/uscnews/stories/9861.html|newspaper=USC News|date=Feb. 2004}}</ref> and twin studies.<ref>{{cite news|title=The Origins of Antisocial Behaviour, Twin Study|url=http://www.medicalnewstoday.com/releases/25078.php|newspaper=Medical News Today|date=May 2005}}</ref> Psychopaths do indeed show brain anomallies, which if not genetic, the author claims that it would indicate the condition is hard-wired from birth. Hare goes on to state that many psychopaths, a malady that arrises primarily in males, have a pattern of mating with, and quickly abandoning women, and as a result, procures a higher fertility rate. It is stated in the book that many of these spawned children will inherit a predisposition to psychopathy. Hare describes the implications as chilling.


==Increase in genetic disorders==
==Increase in genetic disorders==
Line 78: Line 78:
===Cross-Generational Assessment Test Analysis===
===Cross-Generational Assessment Test Analysis===


Some thinkers in the Eugenics/Dysgenics movement, like [http://en.wikipedia.org/wiki/Seymour_Itzkoff Seymour Itzkoff], point to falling cross-generation assessment test scores as evidence that American society has entered into a dysgenic age.<ref>{{cite book|last=Itzkoff|first=Seymour|title=The Decline of Intelligence in America: A Strategy for National Renewal|year=1994|publisher=Praeger|isbn=978-0275952297|url=http://www.amazon.com/Decline-Intelligence-America-Strategy-National/dp/0275952290}}</ref> When standardized test scores are analyzed, it may give this line of thought some validation.
Some thinkers in the Eugenics/Dysgenics movement, like [[Seymour Itzkoff]], point to falling cross-generation assessment test scores as evidence that American society has entered into a dysgenic age.<ref>{{cite book|last=Itzkoff|first=Seymour|title=The Decline of Intelligence in America: A Strategy for National Renewal|year=1994|publisher=Praeger|isbn=978-0275952297|url=http://www.amazon.com/Decline-Intelligence-America-Strategy-National/dp/0275952290}}</ref> When standardized test scores are analyzed, it may give this line of thought some validation.


The American [http://en.wikipedia.org/wiki/SAT SAT] Reasoning Test (formerly the Scholastic Aptitude Test or Scholastic Assessment Test), a standardized test for college admissions in the United States, peaked in the early 1960s<ref>{{cite news|title=Education: Decline in the SATs|url=http://www.time.com/time/magazine/article/0,9171,910920,00.html|newspaper=Time|date=Dec. 1973}}</ref> and then declined precipitously until scores were re-centered with a one-hundred point advantage in 1995. Until then, the number of students who scored above 600 on the verbal portion of the test had slipped from 112,530 in 1972 to 73,080 in 1993, a 36% drop, despite the fact that the total number of test-takers had risen to over 500,000.<ref>{{cite news|last=The Center for Education Reform|title=SAT Increase -- The Real Story, Part II|url=http://www.edreform.com/Press_Box/Press_Releases/?SAT_Increase_The_Real_Story_Part_II&year=1996|date=Aug. 1996}}</ref>
The American [[SAT]] Reasoning Test (formerly the Scholastic Aptitude Test or Scholastic Assessment Test), a standardized test for college admissions in the United States, peaked in the early 1960s<ref>{{cite news|title=Education: Decline in the SATs|url=http://www.time.com/time/magazine/article/0,9171,910920,00.html|newspaper=Time|date=Dec. 1973}}</ref> and then declined precipitously until scores were re-centered with a one-hundred point advantage in 1995. Until then, the number of students who scored above 600 on the verbal portion of the test had slipped from 112,530 in 1972 to 73,080 in 1993, a 36% drop, despite the fact that the total number of test-takers had risen to over 500,000.<ref>{{cite news|last=The Center for Education Reform|title=SAT Increase -- The Real Story, Part II|url=http://www.edreform.com/Press_Box/Press_Releases/?SAT_Increase_The_Real_Story_Part_II&year=1996|date=Aug. 1996}}</ref>


The [http://en.wikipedia.org/wiki/Ellis_Paul_Torrance Torrance Tests of Creative Thinking (TTCT)] - a benchmark for measuring divergent thinking and other problem-solving skills for the last 50 years - - has seen declining scores among all age groups since 1990, but a particularly troublesome decline for children between the ages of kindergarten through sixth grade.<ref>{{cite news|last=Bronson & Merryman|title=The Creativity Crisis|url=http://www.newsweek.com/2010/07/10/the-creativity-crisis.html|newspaper=Newsweek|date=July 2010}}</ref>
The [[Ellis Paul Torrance|Torrance Tests of Creative Thinking (TTCT)]] - a benchmark for measuring divergent thinking and other problem-solving skills for the last 50 years - - has seen declining scores among all age groups since 1990, but a particularly troublesome decline for children between the ages of kindergarten through sixth grade.<ref>{{cite news|last=Bronson & Merryman|title=The Creativity Crisis|url=http://www.newsweek.com/2010/07/10/the-creativity-crisis.html|newspaper=Newsweek|date=July 2010}}</ref>


==Arguments against==
==Arguments against==

Revision as of 04:11, 7 July 2011

Dysgenics (also known as cacogenics) is the study of factors producing the accumulation and perpetuation of defective or disadvantageous genes and traits in offspring of a particular population or species.[1][2] Dysgenic mutations have been studied in animals such as the mouse[3] and the fruit fly.[4][5] The term dysgenics was first used as an antonym of eugenics — the social philosophy of improving human hereditary qualities by social programs and government intervention.[6]

Theories

The word "dysgenic" was first used, as an adjective, about 1915, by David Starr Jordan, describing the dysgenic effect of World War I.[7] Jordan believed that healthy men were as likely to die in modern warfare as anyone else, and that war killed only the physically healthy men of the populace whilst preserving the disabled at home.[8][9]

During 1965, Colum Gillfallen speculated in The Mankind Quarterly that lead used by Romans for plumbing and cooking utensils poisoned the water and food of the Roman elite, causing the decline of the Roman Empire.[10] Gillfallen's theory was refuted during 1985 by Needleman and Needleman, who showed that measurements of lead from bones of Romans and other peoples did not provide any evidence that the fertility of the Roman elite was adversely affected.[11]

The psychologist Robert Hare in his book, "Without Conscience: The Disturbing World of Psychopaths among Us",[12] puts forth the theory that psychopathy has a genetic predispostion. Hare claims are supported in part from brain scans,[13] and twin studies.[14] Psychopaths do indeed show brain anomallies, which if not genetic, the author claims that it would indicate the condition is hard-wired from birth. Hare goes on to state that many psychopaths, a malady that arrises primarily in males, have a pattern of mating with, and quickly abandoning women, and as a result, procures a higher fertility rate. It is stated in the book that many of these spawned children will inherit a predisposition to psychopathy. Hare describes the implications as chilling.

Increase in genetic disorders

Our current ability to treat disorders that were previously lethal or otherwise limited reproduction of affected individuals may have a dysgenic effect. Genetic disorders could become increasingly more common as the negative selection against such disorders declines. This effect would be the least severe in autosomal recessive disorders. For example, if all people affected with the autosomal recessive disease Cystic Fibrosis were capable of reproducing at the same rate as people unaffected by the disease, the incidence of Cystic Fibrosis would increase from 1 in 2000 to 1 in 1550 in 200 years.

In disorders that are normally not inherited, such as lethal autosomal dominant disorders, the increase in newborns affected with the disease as a result of a new treatment allowing those affected to survive beyond childhood and reproduce would be far stronger.

In the same manner as genetic disorders caused by a single gene, disorders caused by multiple genes, or a combination of environmental and genetic factors may become increasingly common as well. An example could be neural tube defects due to folic acid supplementation around conception. People who would normally have been born with a neural tube defect by inheriting genes associated with an increased risk for the disease may instead be born unaffected thanks to vitamin supplementation, and go on to reproduce themselves and pass on the genes associated with the increased risk of neural tube defects.

Another example is a congenital heart defect. Surgery can now effectively treat a congenital heart defect and thus those affected may have children whereas in previous times the disorder may have been lethal at an early age.[15]

Scientists believe such problems have the potential to lead to a progressive increase in various genetic disorders. Some proposals are to screen people for genetic disorders such as Huntingtons disease. Huntington's disease normally only reveals itself late in life when those affected have already had children. If someone carrying the disorders is informed about being affected by the disorder before the symptoms arise, he may possibly choose not to have any children. Other examples of policies considered include embryo selection to choose to implant only embryos unaffected by a genetic disorder while choosing not to implant carriers. In all cases, numerous ethical dilemmas arise.

Intelligence studies

Further information: Heritability of IQ and Fertility and intelligence

William Shockley used the term with his controversial advocacy of eugenics from the mid-1960s through the 1980s. Shockley argued that "the future of the population was threatened because people with low IQs had more children than those with high IQs."[16][17]

Robert Klark Graham 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."[18]

Since 1969, a few studies of differential fertility have theorized that it may cause a decrease of population IQ and isolated studies have reported a negative correlation between IQ and fertility.[19][20][21] During 1996, Richard Lynn wrote Dysgenics: Genetic Deterioration in Modern Populations; Lynn had been previously criticized for distorting and misrepresenting data[22][23][24] although others have favorably reviewed Lynn's work on dysgenics.[25][26][27] Richard Lynn (along with Daniel R. Vining and William Shockley) is a major recipient of grants from the Pioneer Fund, characterized as a hate group by the Southern Poverty Law Center (SPLC),[28][29] a civil rights advocacy organization.

Cross-Generational Assessment Test Analysis

Some thinkers in the Eugenics/Dysgenics movement, like Seymour Itzkoff, point to falling cross-generation assessment test scores as evidence that American society has entered into a dysgenic age.[30] When standardized test scores are analyzed, it may give this line of thought some validation.

The American SAT Reasoning Test (formerly the Scholastic Aptitude Test or Scholastic Assessment Test), a standardized test for college admissions in the United States, peaked in the early 1960s[31] and then declined precipitously until scores were re-centered with a one-hundred point advantage in 1995. Until then, the number of students who scored above 600 on the verbal portion of the test had slipped from 112,530 in 1972 to 73,080 in 1993, a 36% drop, despite the fact that the total number of test-takers had risen to over 500,000.[32]

The Torrance Tests of Creative Thinking (TTCT) - a benchmark for measuring divergent thinking and other problem-solving skills for the last 50 years - - has seen declining scores among all age groups since 1990, but a particularly troublesome decline for children between the ages of kindergarten through sixth grade.[33]

Arguments against

A negative correlation between fertility and IQ has existed in many parts of the world at various times;[34] it has been argued that this was true of Ancient Rome.[11] While it may seem obvious that differential fertility would result in a progressive change of IQ, Preston and Campbell argue that it is a fallacy that applies only to closed subpopulations. As long as the children's IQ can be more or less than that of their parents, an equilibrium is established. Subsequently, the mean IQ will not change in the absence of a change of the differential fertility. The steady-state IQ distribution will be lower for negative differential fertility and for positive, but these differences are small. For the extreme and unrealistic assumption of endogamous mating in IQ subgroups, a differential fertility change of 2.5/1.5 to 1.5/2.5 (high IQ/low IQ) causes a maximum shift of four IQ points. For random mating, the shift is less than one IQ point.[35]

James S. Coleman, however, contends that Preston and Campbell's model depends on assumptions which are unlikely to be true, and argues that their dismissal of the "common belief" in the case of IQ is unfounded.[36][37]

Flynn effect

Main article: Flynn effect

The increase of IQ scores since their development provides evidence against dysgenic decreases of IQ; this general increasing trend is known as the Flynn effect. Geneticist Steve Connor wrote that Lynn, writing in Dysgenics: Genetic Deterioration in Modern Populations, "misunderstood modern ideas of genetics." "A flaw in his argument of genetic deterioration in intelligence," Jones said in his refutation of the existence of a dysgenic trend, which "was the widely accepted fact that intelligence as measured by IQ tests has actually increased over the past 50 years."[38]

If the genes causing IQ have been shifting, IQ throughout the population should be reasonably expected to shift in the same direction, yet the reverse has occurred. However, genotypic IQ may decrease even while phenotypic IQ rises throughout the population due to environmental effects such as better nutrition and education.[39][better source needed] The Flynn effect has increased IQ scores as much as 15 points throughout the First World, but recent research shows it is reversing in Northern Europe and possibly elsewhere.[40][41][42][43][44]

In fiction

Cyril M. Kornbluth's 1951 short story The Marching Morons is an example of dysgenic fiction, describing a man who accidentally ends up in the distant future to find out that dysgenics has resulted in mass stupidity. Mike Judge's 2006 film Idiocracy has the same premise, with the main character the subject of a military hibernation experiment that goes awry, taking him 500 years into the future. While in the Kornbluth short story civilization is kept afloat by a small group of dedicated geniuses, their function has been replaced by automated systems in Idiocracy.[45]

See also

Notes

  1. ^ http://www.bartleby.com/61/60/D0446000.html
  2. ^ http://medical.merriam-webster.com/medical/dysgenics
  3. ^ Tanabe T, Beam KG, Powell JA, Numa S (1988). "Restoration of e xcitation-contraction coupling and slow calcium current in dysgenic muscle by dihydropyridine receptor complementary DNA". Nature. 336 (6195): 134–9. doi:10.1038/336134a0. PMID 2903448. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  4. ^ Kidwell MG (1983). "Evolution of hybrid dysgenesis determinants in Drosophila melanogaster". Proc. Natl. Acad. Sci. U.S.A. 80 (6): 1655–9. doi:10.1073/pnas.80.6.1655. PMC 393661. PMID 6300863. {{cite journal}}: Unknown parameter |month= ignored (help)
  5. ^ Almeida LM, Carareto CMA (June 2002). "Gonadal hybrid dysgenesis in Drosophila Sturtevanti (Diptera, Drosophilidae)". Iheringia, Sér. Zool. 92 (2). doi:10.1590/S0073-47212002000200007.
  6. ^ "cacogenics". Freedictionary.com. Retrieved 2008-06-29. Cacogenics, the study of the operation of factors that cause degeneration in offspring, especially as applied to factors unique to separate races. Also called dysgenics.
  7. ^ Oxford English Dictionary
  8. ^ Jordan, David Starr (2003 (Reprint)). War and the Breed: The Relation of War to the Downfall of Nations. University Press of the Pacific. ISBN 1-4102-0900-8. {{cite book}}: Check date values in: |date= (help); Unknown parameter |locat ion= ignored (help)
  9. ^ McNish I (Fall 2002). "David Starr Jordan on the Dysgenic effects of dysfunctional culture". Mankind Quarterly. 43 (1): 81–98.
  10. ^ Gillfallen SC (January–March 1965). "Roman Culture and Dysgenic Lead Poisoning". The Mankind Quarterly. 5 (3): 131–148. ISSN 0025-2344.
  11. ^ a b Needleman L, Needleman D (1985). "Lead Poisoning and the Decline of the Roman Aristocracy". 4 (1): 63–94. ISSN 0012-9356. {{cite journal}}: Cite journal requires |journal= (help); Unknown parameter |jo urnal= ignored (help)
  12. ^ Hare, R. (1999). Without Conscience. The Guilford Press. pp. 70, 166–177. ISBN 1-57230-451-0.
  13. ^ Sutliff, U (Feb. 2004). "Out of Order". USC News. {{cite news}}: Check date values in: |date= (help)
  14. ^ "The Origins of Antisocial Behaviour, Twin Study". Medical News Today. May 2005.
  15. ^ Nussbaum, McInnes, Willard, Thompson (2004). Thompson and Thompson genetics in medicine. Saunders. pp. 396–397. ISBN 0-7216-0244. {{cite book}}: Check |isbn= value: length (help)CS1 maint: multiple names: authors list (link)
  16. ^ "William Shockley 1910–1989". A Science Odyssey People and Discoveries. PBS online. 1998. Retrieved 2006-11-13.
  17. ^ William Shockley, Roger Pearson: Shockley on Eugenics and Race: The Application of Science to the Solution of Human Problems Scott-Townsend Publishers, ISBN 978-1878465030
  18. ^ Graham RK (Fall 1998). "Devolution by revolution: Selective genocide ensuing from the French and Russian revolutions". Mankind Quarterly. 39 (11): 71–93.
  19. ^ Kirk D (1969). "The biological effects of family planning. B. The genetic implications of family planning". J Med Educ. 44 (11): Suppl 2:80–3. PMID 5357924. {{cite journal}}: Unknown parameter |month= ignored (help)
  20. ^ Vining, Daniel (1995). "On the possibility of the reemergence of a dysgenic trend with respect to intelligence in American fertility differentials: an update". Personality and Individual Differences. 19 (2): 259–263. doi:10.1016/0191-8869(95)00038-8.
  21. ^ Lynn R, Van Court M (2004). "New evidence of dysgenic fertility for intelligence in the United States". Intelligence. 32 (2): 193–201. doi:10.1016/j.intell.2003.09.002.
  22. ^ Leon K (February 1995). "The Bell Curve: Intelligence and Class Structure in American Life". Scientific American. 272. Lynn's distortions and misrepresentations of the data constitute a truly venomous racism, combined with scandalous disregard for scientific objectivity.
  23. ^ Rosenthal S. "Academic Nazism". Department of Sociology, Hampton University. Retrieved 2008-06-28.
  24. ^ Berhanu G. "Black Intellectual Genocide: An Essay Review of IQ of Wealth of Nations" (PDF). Gotberg University, Sweden. Retrieved 2008-06-28.
  25. ^ 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. Retrieved 2008-05-11.
  26. ^ Loehlin JC (1999). "Dysgenics: Genetic Deterioration in Modern Populations, reviewed by John C. Loehlin" (fee required). Annals of the American Academy of Political and Social Science.
  27. ^ Vining DR (1998). "Dysgenics: Genetic Deterioration in Modern Populations, reviewed by Daniel R. Vining, Jr" (fee required). Population Studies.
  28. ^ "Race and 'Reason'; Academic ideas a pillar of racist thought". Southern Poverty Law Center. Retrieved 2008-04-15.
  29. ^ "Into the Mainstream; An array of right-wing foundations and think tanks support efforts to make bigoted and discredited ideas respectable". Southern Poverty Law Center. Retrieved 2008-04-15.
  30. ^ Itzkoff, Seymour (1994). The Decline of Intelligence in America: A Strategy for National Renewal. Praeger. ISBN 978-0275952297.
  31. ^ "Education: Decline in the SATs". Time. Dec. 1973. {{cite news}}: Check date values in: |date= (help)
  32. ^ The Center for Education Reform (Aug. 1996). "SAT Increase -- The Real Story, Part II". {{cite news}}: Check date values in: |date= (help)
  33. ^ Bronson & Merryman (July 2010). "The Creativity Crisis". Newsweek.
  34. ^ Literacy, Education and Fertility, Past and Present: A Critical Review, Harvey J. Graff
  35. ^ Preston SH, Campbell C (March 1993). "Differential Fertility and the Distribution of Traits: The Case of IQ" (fee required). The American Journal of Sociology. 98 (5). The University of Chicago Press: 997–1019. doi:10.1086/230135. Retrieved 2008-04-22.
  36. ^ Coleman JS (1993). "Comment on Preston and Campbell's 'Differential Fertility and the Distribution of Traits'" (fee required). The American Journal of Sociology. 98 (5): 1020–1032. doi:10.1086/230136.
  37. ^ Lam D (March 1993). "Comment on Preston and Campbell's "Differential Fertility and the Distribution of Traits"" (fee required). The American Journal of Sociology. 98 (5). The University of Chicago Press: 1033–1039. doi:10.1086/230137. Retrieved 2008-04-22.
  38. ^ Connor, Steve (December 22, 1996). "Stalking the Wild Taboo; Professor predicts genetic decline and fall of man". The Sunday Times. Retrieved 2008-04-15.
  39. ^ Retherford RD, Sewell WH (1988). "Intelligence and family size reconsidered" (PDF). Soc Biol. 35 (1–2): 1–40. PMID 3217809.
  40. ^ Teasdale T, Owen DR (2008). 0c1b02 "Secular declines in cognitive test scores: A reversal of the Flynn Effect". Intelligence. 36 (2): 121. doi:10.1016/j.intell.2007.01.007. {{cite journal}}: Check |url= value (help)
  41. ^ Lynn R, Harvey J (2008). "The decline of the world's IQ". Intelligence. 36 (2): 112. doi:10.1016/j.intell.2007.03.004.
  42. ^ Gray, Richard (February 7, 2009). "British teenagers have lower IQs than their counterparts did 30 years ago". London: The Telegraph.
  43. ^ Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1016/j.ehb.2009.01.009, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with |doi=10.1016/j.ehb.2009.01.009 instead.
  44. ^ Teasdale TW & Owen DR (2005). "A long-term rise and recent decline in intelligence test performance: The Flynn Effect in reverse". Personality and Individual Differences. 39 (4): 837–843. doi:10.1016/j.paid.2005.01.029.
  45. ^ Mitchell, Dan (2006-09-09). "Shying away from Degeneracy". The New York Times. Retrieved 2008-06-29.

Further reading

  • Devlin, Bernie; Fienberg, Stephen E.; Resnick, Daniel P.; Kathryn, eds. (1997). Intelligence, Genes, and Success: Scientists Respond to the Bell Curve. New York (NY): Springer. ISBN 978-0-387-94986-4. {{cite book}}: Invalid |ref=harv (help); Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |laydate= ignored (help); Unknown parameter |laysummary= ignored (help)
  • Neisser, Ulric, ed. (1998). The Rising Curve: Long-Term Gains in IQ and Related Measures. APA Science Volume Series. Washington (DC): American Psychological Association. ISBN 978-1-55798-503-3. {{cite book}}: Invalid |ref=harv (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
Retrieved from "https://en.wikipedia.org/w/index.php?title=Dysgenics&oldid=438174893"