A long childhood and late reproduction are proposed to pay off because the skills acquired raise productivity enough to fund a longer life.
Kaplan's data showed forager hunting productivity peaking well into adulthood, decades after physical strength does, which points at learned skill rather than the body as the constraint. The model treats the long juvenile period as an investment with a measurable return, and predicts that societies with harder-to-learn subsistence will have later peaks.
In practice
- A profession where competence peaks at fifty selects for people who could afford twenty years of training.
- An apprenticeship that runs longer than the job seems to need is buying productivity that arrives later.
- Possible explanations
- The explanation is investment: a long childhood buys learned skill, and where the skill raises productivity for decades, the delayed payoff justifies the slow start and the longer life needed to collect it.
- In its favour
- It fits forager productivity data, where hunting returns peak well after physical strength does, which points at learned skill rather than the body.
- Against it
- It is contested against grandmothering and other accounts of the same life-history pattern, and the direction of causation is difficult to establish from comparative data alone.
- Standing
- Fits forager productivity data reasonably well and is contested against grandmothering and other accounts of the same life-history pattern.
- Subject
- Sociology & Culture
- Essay
- How societies hold together, sort people, and change