The Nature of Nurture: Rethinking Why and How Childhood Adversity Shapes Development

Belsky (The Origins of You), a professor of human development at University of California-Davis, draws on evolutionary biology for this uneven exploration of how adverse upbringings affect development. Kids who experience poverty, abuse, and unstable family relationships early in life frequently grow up to display behaviors like recklessness, aggression, and early sexual activity, and have a higher likelihood of providing limited parental care to their own kids. These behaviors are not actually dysfunctional, according to Belsky, but are adopted to maximize chances of passing on one’s genes in an uncertain environment. Not all kids raised under challenging circumstances grow up to be reckless, however, just as not all kids from stable homes become responsible. This can also be explained by evolutionary biology, Belsky notes, explaining that the differential susceptibility hypothesis holds that kids differ in developmental “plasticity,” rendering them more or less susceptible to environmental influences. Having children of various plasticities in a single family, then, is an evolutionary version of “bet hedging” that produces a range of behavioral strategies for finding reproductive success. While Belsky’s theory intrigues, it’s weakened by jargon-heavy writing and vague descriptions of supporting data. Lay readers curious about the subject would be better served by Matt Ridley’s Nature via Nurture or Steven Pinker’s The Blank Slate. (Jan.)