Intelligence and fertility in the United States: 1912–1982

New evidence of dysgenic fertility for intelligence in the United States

“…Some studies carried out in the United States in the 1960s suggested that dysgenic fertility had already disappeared and therefore that the eugenic hypothesis was right (Bajema, 1993;Higgins, Reed, & Reed, 1992). However, several studies in the 1980s found that dysgenic fertility was still present (Retherford & Sewell, 1988;Van Court & Bean, 1985;Vining, 1982). This paper presents new data on this issue for the United States collected during the years 1990-1996.…”

“…First, it goes some way towards resolving the problem of the differences between the Higgins et al (1992) and the Bajema (1993) studies, showing a positive relationship between intelligence and fertility, and the Van Court and Bean (1985), Vining (1982Vining ( , 1995, and the Retherford and Sewell (1988) studies, showing a negative relationship. The results of the present study confirm and extend the second set of studies in that they show that the association between intelligence and fertility has been consistently negative for all birth cohorts from 1900-1919 up to 1970-1979.…”

“…The GSS data for the years 1974, 1976, 1978, and 1982 were analyzed for the relationship between vocabulary scores and fertility by Van Court and Bean (1985). The reason for using these years was that the vocabulary test is not given every year and these were the years in which it was given during the period 1974-1982.…”

How fragile is our intellect? Estimating losses in general intelligence due to both selection and mutation accumulation

“…(III) A correction is implemented based on whether parameter S was determined on the basis of the IQ/sibship correlation. Van Court and Bean (1985) found that these correlation magnitudes were larger than those based on the IQ/completed fertility relationship when estimated using the same large sample of the US population (À.31 vs À.18). Decline estimates based on sibship may be inflated by within-family sources of IQ variance that are independent of dysgenics (e.g.…”

The Wisdom of Nature: An Evolutionary Heuristic for Human Enhancement

“…In the current age, however, literacy is in very high demand. Failing to meet this demand places an individual at a severe disadvantage (Udry 1978;Vancourt and Bean 1985;Vining, Bygren, Hattori, Nystrom and Tamura 1988). This might be an example of value discordance between human values and evolutionary fitness.…”