Childhood Behavioral Differences in Boys vs. Girls | Carole Hooven, Ph.D.

The gist

1. A testosterone surge peaking around 3 months after birth, called mini puberty, shapes brain development and explains higher activity levels in boys on average.
2. Current testosterone levels are poor predictors of behavior in children; variation within each sex far exceeds the average differences between sexes.
3. Rough-and-tumble play helps boys learn to navigate social hierarchies and may reduce aggression over time, but displacement by screens could undermine this.
4. Sex differences in play, like boys favoring competition and girls favoring nurturing, trace back to evolved reproductive strategies, though individual variation is large.