Source pages: Quotes batch 21
Quote pages: Sapolsky – Behave
“Heritability of various aspects of cognitive development is very high (e.g., around 70 percent for IQ) in kids from high–socioeconomic status (SES) families but is only around 10 percent in low-SES kids. Thus, higher SES allows the full range of genetic influences on cognition to flourish, whereas lower-SES settings restrict them. In other words, genes are nearly irrelevant to cognitive development if you’re growing up in awful poverty — poverty’s adverse effects trump the genetics.”
The genes-vs-environment debate is malformed. Environment determines how much genes matter. Genes and environment are not additive; they multiply. See genes-are-not-destiny for the fuller treatment of context-dependent genetic expression.
Gender and math: culture, not biology
“The more gender equal the country, the less of a discrepancy in math scores. By the time you get to the Scandinavian countries it’s statistically insignificant. And by the time you examine the most gender equal country on earth at the time, Iceland, girls are better at math than boys… In other words, culture matters. We carry it with us wherever we go.”
A finding that looks biological disappears when cultural context changes. The sex difference in math scores is a cultural artifact. Note: the sex difference in reading favoring girls grows in more equal societies — an asymmetry that resists simple cultural or biological explanations.
Individualism as immigrant selection
“who were the immigrants? Those in the settled world who were cranks, malcontents, restless, heretical, black sheep, hyperactive, hypomanic, misanthropic, itchy, unconventional, yearning… America has had a moving frontier luring those whose extreme prickly optimism made merely booking passage to the New World insufficiently novel.”
American individualism is not cultural accident; it is the product of consecutive selection events — emigration, then frontier migration — that systematically filtered for the most individualistic among each generation. See collectivist-vs-individualist for the broader ecological framing (rice vs wheat farming).
In-group trust and the amygdala
“the default state is to trust, and what the amygdala does is learn vigilance and distrust.”
Contrary to the popular picture, humans are not naturally suspicious. Trust is the baseline; the amygdala learns distrust through experience. This has implications for how prejudice works — it is not innate but acquired through exposure to environments that teach threat associations. See in-group-out-group and oxytocin for the prosocial/xenophobic duality.
Morality: evolved for genes, not flourishing
“Why is it that our automatic, intuitive moral judgments tend to be nonutilitarian? Because, as Greene states, ‘Our moral brains evolved to help us spread our genes, not to maximize our collective happiness.’”
Moral intuitions are not reliable guides to ethical action. They were selected for inclusive fitness, not human welfare. This is why disgust responses track conservative politics:
“social conservatives tend toward lower thresholds for disgust than liberals.”
Disgust is an ancient contamination-avoidance system, hijacked to police social and moral boundaries. See dual-process-cognition for the System 1 / moral intuition link.