Why intelligence depends more on enviroment than genitic factor . explain?
Answers
Most of the evidence shows that aside from extreme deprivation there is little one can do to substantially reduce someones ability to reach their full potential level of intelligence. If a child is exposed to extreme stress, high lead levels and is chronically malnourished it's very likely their intelligence levels will be stunted. Much research has gone into finding possible ways to boost intelligence, through nutritional supplements and early exposure to cognitively stimulating environments, the results show it is very difficult to boost intelligence. Intelligence is very stable during Childhood, an IQ test at age 6 correlates with IQ scores in adulthood at a shockingly high .85.
This is using data in which the IQ was tested *three times* over the interval listed and the results averaged. A single measurement at age 5 would probably do worse than what is listed below. Unfortunately there are only 61 kids in the study.
age range correlation with adult score
42,48,54 months .55
5,6,7 .85
8,9,10 .87
11,12,13 .95
14,15,16 .95
Intelligence was assessed with the WISC at a mean age of 9.5. Twenty‐six subjects were retested with the WAIS at a mean age of 23.5, and 78 subjects with the BPP (the Danish Military Draft Board Intelligence Test) at the age of 19.1. Both samples obtained childhood and adult test scores below the expected means. For the Wechsler Verbal, Performance and Full‐Scale IQs, the stability quotients were 0.86, 0.86, and 0.89 in the WAIS sample, and the retest correlations for the three IQs with the BPP score were 0.66, 0.65, and 0.74. Thus, the majority of children showed stable patterns of intellectual development from middle childhood to young adulthood.