> these days people can grow into functional adults first, which might not happen until their late 30's. Some (many?) won't. Adult means taking responsibility

> these days people can grow into functional adults first, which might not happen until their late 30's. Some (many?) won't. Adult means taking responsibility for your own actions to me. In "archaic" societies, girls become women at the onset of their period. Boys have to undergo painful rituals to become a man. No puberty problems or teenage suicides in sight because these young humans have their place in the tribe and are treated like the young adults they are. No artificial age barriers (18/21). The brain is actually done at myelinizing at 25.