The Danish psychologist Helmuth Nyborg has an academic paper soon to be published in Personality and Individual Differences (“The decay of Western Civilization: Double Relaxed Natural Selection“). Nyborg is well-known for his work showing a sex difference in IQ favoring males, a paper which resulted in an investigation of his work and a reprimand from his university. (Nyborg describes the “witch hunt” he endured here.)
Nyborg’s latest paper charts past trends and projects IQ changes in Denmark as a result of two trends: relaxation of natural selection among the traditional Danes, and an influx of low-IQ immigrants. These two trends together amount to what he terms a “double relaxation of natural selection” (DRNS).
Relying on Richard Lynn’s work Dysgenics: Genetic Deterioration in Modern Populations, the relaxation of internal selection is thought to have begun around 1850 as the fertility of the lower classes exceeded the upper classes because of improvements in hygiene and reduction in diseases. He cites Lynn’s estimate that England lost 6.9 IQ points over 90 years (1920-2010) and estimates that Denmark’s average IQ dropped around 10 points since 1850 due to internal relaxation of natural selection. Read more