Much has been made about the 15 point IQ gap between American blacks and whites, but much less is known about the far greater 70 point IQ gap between the most prosperous 0.00001% of Americans (currently self-made decabillionaires) and poorest 0.09% of Americans (currently the homeless). The 70 point IQ gap was first discovered by Pumpkin Person in February 2016, citing studies showing the average homeless American has an IQ of about 80 (U.S. white norms) and the average American self-made decabillionaire has an IQ perhaps as high as 150.
According to the American Psychological Association, the heritability of IQ is 0.75 by the late teens. The square root of the heritability implies an astonishing 0.86 correlation between IQ geneotype and IQ phenotype. Note, this correlation is for adopted people, used in heritability studies to separate the effects of genes from environment. The genotype-phenotype correlation among ALL Americans might be even higher than 0.86 because among the non-adopted, good genotypes tend to be raised in good homes.
Assuming a 0.86 correlation between genetic IQ and phenotypic IQ, the 70 point IQ gap between the richest and the poorest implies a 0.86(70) = 60 point gap in genetic IQ between these two financial extremes. The idea that there could be a 4 standard deviation (SD) gap in genetic ability between the richest and poorest Americans is devastating news to female social science PhDs who subscribe to the notion that we are all a product of society, not our inherent individual merits.
But commenter “Mugabe” has argued that IQ heritability estimates are misleadingly high because even the best studies (those of identical twins raised apart) seldom, if ever, compare people born and raised in different countries, so we don’t know if the genetic effects are environment independent, or if both were reared in a different country or different generation, the homeless genotype might have had a higher IQ (or more money) than the self-made decabillionaire genotype. This is known as the “reaction norm” argument.
However at least a big chunk of the 70 point IQ gap is caused by independent genetic effects. For example, the 0.33 correlation between IQ and brain size implies the average self-made deca-billionaire has a brain 1.54 SD bigger than the average homeless brain, and even “Mugabe” agrees that physical genotypes are much less sensitive to reaction norms than psychological ones, and scholar Arthur Jensen notes that the preponderance of evidence reveals g (general intelligence) to be an ENTIRELY physiological trait, not amenable to psychological manipulation.
The difference between the average homeless person and the average self-made decabillionaire start early in life. According to Wikipedia, a typical self-made deca-billionaire like Sergey Brin Brin was born in Moscow in the Soviet Union, to Russian Jewish parents, Yevgenia and Mikhail Brin, both graduates of Moscow State University (MSU).[9][10] His father is a mathematics professor at the University of Maryland, and his mother a researcher at NASA‘s Goddard Space Flight Center.[1][11][12].
In honor of Halloween, I will use Michael Myer’s from Rob Zombies Halloween series as the example of a typical homeless (Myers was hard-core homeless in Zombie’s Halloween II). He was born to a stripper mother and a dead father, and raised in a white trash middle American home.
According to Wikipedia, “Brin attended elementary school at Paint Branch Montessori School in Adelphi, Maryland, but he received further education at home; his father, a professor in the department of mathematics at the University of Maryland, encouraged him to learn mathematics and his family helped him retain his Russian-language skills”.
By contrast, young Michael Myers spent his childhood upstairs in his bedroom, wearing a clown mask and killing his pet rat, while his stripper mother and her white trash boyfriend, argued violently downstairs.
So even by the age of ten, you could tell that Brin and Myers were destined to have very different lives.
Wikipedia tells us that as a young adult Brin enrolled in the University of Maryland, where he received his Bachelor of Science from the Department of Computer Science in 1993 with honors in computer science and mathematics, which is part of the University of Maryland College of Computer, Mathematical, and Natural Sciences.[17]
By contrast, Myers’s education ended in the fifth grade, when he was confined to a mental hospital for brutally murdering his classmate, his slutty sister, her boyfriend, and his mom’s drunken boyfriend. While Brin was getting his advanced degrees, Myers was rotting in a cell, not speaking, just making primitive paper mache Halloween masks over and over and over again.
By his 30s Brin was a self-made billionaire.

Self-made decabillionaire Sergey Brin of Google
By Myers’s 30s, he had escaped from a mental hospital, went on a massive killing spree, and after falsely being declared dead, spent the rest of his life roaming the fields of Haddonfield, Illinois as a homeless man, eating dogs to stay alive.

The homeless Michael Myers from Rob Zombie’s Halloween II
While Brin advances even his ethnic genetic interests by generously donating to the Hebrew national Immigrant Aid Society, Myers destroyed his immediate genetic interests, by killing his older sister, and getting himself and younger sister shot by the police.