25 Sept., 2015

The chimpanzee effect confirmed



For some years now, I have been talking about a chimpanzee effect.  The idea is that at 6 months of age a chimpanzee baby is much more able in all ways than is a 6 month old human baby. But a human baby grows to be a much smarter adult that does a chimp.  So in assessing IQ, early measurements can be misleading.  So we find that the IQ gap between blacks and whites tends to become greater as time goes by.  In their brain-dead way Leftists tend to interpret the widening gap in various adverse ways.  They say that blacks start out smart but "whites" somehow oppress them.  They fail to take note that chimps develop earlier too.  And chimp IQ certainly does not plateau early because of "racism" or "oppression".

At no point, of course have I compared blacks to chimps.  I am just using the term "chimpanzee effect" as a vivid term for the general rule that final IQ will be reached more slowly the higher is the final level.

So I am rather pleased that the recent journal article below finds that effect in a solely human population. In the study below, lower socio-economic status children fill the role of chimps in my thesis.  But note again that I am not comparing ANY humans to chimps.  I am just pointing out what an initial high or low IQ finally leads to.  It may be worth noting that the final age in the study below was 16.  That age is usually found to be the point beyond which IQ does not develop further.

Socioeconomic status and the growth of intelligence from infancy through adolescence

by Von Stumm, Sophie and Plomin, Robert.

Abstract

Low socioeconomic status (SES) children perform on average worse on intelligence tests than children from higher SES backgrounds, but the developmental relationship between intelligence and SES has not been adequately investigated. Here, we use latent growth curve (LGC) models to assess associations between SES and individual differences in the intelligence starting point (intercept) and in the rate and direction of change in scores (slope and quadratic term) from infancy through adolescence in 14,853 children from the Twins Early Development Study (TEDS), assessed 9 times on IQ between the ages of 2 and 16 years. SES was significantly associated with intelligence growth factors: higher SES was related both to a higher starting point in infancy and to greater gains in intelligence over time. Specifically, children from low SES families scored on average 6 IQ points lower at age 2 than children from high SES backgrounds; by age 16, this difference had almost tripled. Although these key results did not vary across girls and boys, we observed gender differences in the development of intelligence in early childhood. Overall, SES was shown to be associated with individual differences in intercepts as well as slopes of intelligence. However, this finding does not warrant causal interpretations of the relationship between SES and the development of intelligence.

SOURCE

Footnote: The article Nature Helps Create Religious Adults reports something similar about religiosity in that genes come to the fore as an influence on religion as the person matures in age




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